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Below are the 20 most recent journal entries recorded in pahawkowl's LiveJournal:

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    Tuesday, December 27th, 2011
    2:12 pm
    Citations to the Previous Post
    I could not find the McKinney paper. Here's the Pierotti and Annett:

    Pierotti, R., and C. Annett. 1994. PATTERNS OF AGGRESSION IN GULLS: ASYMMETRIES AND TACTICS
    IN DIFFERENT SOCIAL CATEGORIES. The Condor 96 (3): 590-599.

    For more information about Mallard aggression, consult the Mallard BIRDS OF NORTH AMERICA life history.
    Monday, December 26th, 2011
    5:05 pm
    Mallard Homicide
    In 1991-2, at Lake Muhlenberg, a pond in Cedar Beach Park, a suburban park in western Allentown, PA, USA, the public was feeding the Mallards so much bread that the pond was full of ducks. Pretty soon in 1991 birds were ganging up on one another and "space and chasing" each other aggressively (term by late Dr. Frank McKinney) to shore where the back of the neck would be snapped by an aggressor bill, causing death. A classic case of "density-dependent" (term in ecology) mortality, it reminds me of too many molecules in one space or too many balls on a pool table, the more there are then more friction there is. There was an island in the middle of the pond, and workers were using it as a cemetery!
    Mostly, if not invariably, domestic x wild hybrids were the victims. This may have happened in part, too, to save up resources (food) for non-sterile pure breeds to guarantee energy for reproduction. But I saw limited direct evidence of courtship and copulating, though some, despite all this happening in the spring.
    It is interesting to note that Pierotti and Annett (1994) found social class (age, sex, and territorial status) asymmetries in success in territorial aggression between nesting Western Gulls in a packed breeding colony. I did not have banding privileges, and it did not occur to me to try to track individuals by their unique plumages and other markings. But Pierotti and Annett observed discrete social behavioral patterns according to status in the flock, which determined success, i.e. whether the territory holder succeeded in holding off the attacker.
    It was another space saturation situation. Established males were able to hold off almost all attackers. Unestablished males came second. Established females were able to hold off all except for adult males. Then came unestablished females.
    Who knows, maybe the same dynamics were occurring at Lake Muhlenberg. One needs a pond and wild Mallards, feed them ad libitum, in the breeding season, and take copious notes!
    Happy holidays, everyone!
    Monday, July 11th, 2011
    4:16 am
    Misc. Bird Study
    How many of us ever got to know a wild animal? I do not mean merely to meet with one once or twice…but to really know it for a long time…and to get an insight into life and history.

    - Earnest Thompson Seton in THE AMERICAN CROW AND THE COMMON RAVEN by Lawrence Kilham

    AMATEUR ORNITHOLOGY

    Grant Stevenson
    Director and Amateur Ornithologist
    GreenSpace Unlimited
    946 Seneca Street, Suite 11
    Bethlehem, PA 18015
    Phn 610-867-2862
    Fax 610-866-6234; call first
    Email: surnia_ulula_caparoch@verizon.net
    2001





    Stevenson -2- Avian Behavioral Ecology


    1. COMMON BIRD BEHAVIOR: Introduction

    The study of animal behavior, or ethology, is called by the British “behavioral ecology”, a term I prefer personally because I believe it describes it best and is all-encompassing on
    the subject. For instance, behavioral ecology also studies human behavior, though not often. It also is not afraid of biological theory (hence the journal, The Journal of Biological Theory). I have had the privilege of belonging to Oxford’s The International Society for Behavioral Ecology (ISBE), which publishes the good journal BEHAVIORAL ECOLOGY. Behavioral Ecology is not interested in “how”, morphological and physiological questions, but “why”, evolutionary adaptive questions. What is the selective reason for this behavior? How does it help the bird “cope” (adapt) to its environment? As you can see, behavioral ecology has helped the sciences of psychology and neuropsychiatry endlessly. The comparative method is widespread in organismal behavioral science. It allows scientists and amateurs to compare different species from different families, orders, and even classes (mammals, birds: higher vertebrates) if the evolutionary reason for the two similar behaviors is the same. Originally used by morphologists, Konrad Lorenz of Germany, one of two fathers of animal behavior, with Niko Tinbergen of Norway in mid-last century, applied it to the behavior of waterfowl and gulls, respectively. Another method is contentious among professional ornithologists: whether to "tame" your subject species, say with whole kernel corn with American Crows (Corvus brachyrhynchos), so they will act close and natural around you, or whether such taming causes them to act in unnatural ways. Many raptor biologists cite studying manned raptors in falconry, with its training, for hunting data, as artificial. I personally do not know the answer to the taming issue. It may depend on what species, what journal, how you write it and account for possible anthropomorphic effects, if you can account for them all, and whether the species has the intelligence to be tamed in the first place (more on cognitivity in birds later- see crow section).

    Stevenson -3- Avian Behavioral Ecology

    For further reading on behavioral ecology, start with BEHAVIOURAL ECOLOGY: AN EVOLUTIONARY APPROACH by John R. Krebs and Nicholas B. Davies. Then read ANIMAL BEHAVIOR: AN EVOLOUTIONARY APPROACH by
    John Alcock. These are the best overviews. The Alcock book is more readable and palatable to the birder, but Krebs and Davies wrote BEHAVIOURAL ECOLOGY: AN INTRODUCTION for that purpose, too. For an understanding of animal signals, such as bird vocalizations, see THE BEHAVIOR OF COMMUNICATING: EA ETHOLOGICAL APPROACH by W. John Smith, the doctoral advisor at The University of Pennsylvania of Dr. Robert Ricklefs, the foremost avian ecologist in the United States. If you want an understanding of bird ecology, I suggest AVIAN ECOLOGY by Christopher Perrins and T.R. Birkhead. Dr. Perrins is the current Director of the Edward Grey Institute of Field Ornithology at Oxford. This book is quite understandable, and affordable, at www.buteobooks.com. For you closet ornithologists, try THE ECONOMY OF NATURE by Dr. Ricklefs. AVIAN ECOLOGY is more oriented toward field avian ecology, but this book delves into depth more what every serious student should know. (Bob Ricklefs and Sir John Krebs are very interested in helping the amateur. I will ask them if they can help you via email once I get five names- via email- no more, and if they are not too busy, they can converse with you and preview your papers prior to submittal.) Do not, I repeat, do not buy these books unless you are particularly flush and can afford it. If you can afford used textbooks, try www.harvestbooks.com. Otherwise, I always get them through Inter-library Loan from my public library and take notes and take down the
    Stevenson -4- Avian Behavioral Ecology

    citation. Simple as that: all I have to pay for is the minimal ILL fee. The general rule of thumb regarding textbooks is of two schools: one, newest editions have the most up to
    date information, such as in biology, and two: subsequent editions don’t offer much m
    information but, with the permissions of the authors, publishing companies make more business in a hard business by putting out more-and-more editions, like in statistics texts. It is subject-dependent, and up to the reader/user. Also, I suggest ON AGGRESSION, KING SOLOMON’S RING, and [book on ethology and the Greylag Goose] by Konrad Lorenz and THE CURIOUS NATURALIST and THE HERRING GULL’S WORLD by Niko Tinbergen. There are other important books by these two, and papers, in the textbooks’ bibliographies. But some of their material is out-dated. For an example, call The University of Oxford Press in the U.S. and request free sample of BEHAVIORAL ECOLOGY journal at 1-800-852-7323 (jnlorders@oup-usa.org). If you have the funds, a student membership to the ISBE is $38; a regular one is $65. I highly recommend Donald Stokes’s A GUIDE TO BIRD BEHAVIOR, VOLUME 1, of all common species; though some subsequent scientific published papers have altered some of the book’s information, much of it still holds true. Stokes was the first to write an entire book of avian behavior for popular consumption, and ILL can find it in public libraries and. As you know, the scientific process means it is constantly being rewritten: Stokes was the first compendium that updated the classics since Catesby, Bartram, Audubon, Wilson, and the 19th and 20th century classics like Ridgeway, Coues, Bendire, Baird, Cooper, Chapman, Grinnell,

    Stevenson -5- Avian Behavioral Ecology


    Griscom, Bent, Sutton, Griscom, Heinrich, Davies, Krebs, etc., in readable, palatable form for the public.
    For a partial, scientific, short course-outline of ethological concepts and theory, see Appendix I. It may behoove you to take an undergraduate course in ornithology. Stephen Kress's out-of-print book THE AUDUBON SOCIETY HANDBOOK FOR BIRDERS has such a list of colleges and courses in the back (see libraries or Harvest Books website). Muhlenberg College has an ornithology course for biology majors during the day and a non-major BIOLOGY OF BIRDS course in the evening adult Wescoe School. Adults can take for credit or audit either. Cornell University offers a BIRD BIOLOGY course through the computer through its Cornell Lab of Ornithology. In order to take it, you must pay for it or get a full scholarship through the Lab. Or you can buy their book HANDBOOK OF BIRD BIOLOGY for $99.50 (65 pounds) from Princeton Universty Press (www.pup.princeton.edu).

    AMERICAN ROBINS

    Definitions

    Optimal foraging is a behavioral ecological term defined by Robert E. Ricklefs (1993, The economics of nature, W.H. Freeman, New York.) as “a set of rules, including breadth of diet, by which organisms maximize food intake per unit time or minimize the time needed to meet their food requirements; risk of predation may also enter the equation for optimal foraging”. Optimal giving up time (GUT) is “the time that an organism should remain within a patch of resources before moving onto the next in order to maximize its rate of food intake”. Optimization of foraging is discussed in detail by Krebs (1984, Behavioural ecology: an evolutionary approach, Sinauer Associates, Inc., Sunderland, MA, for newer editions, and Blackwell Scientific Publications, Oxford, for earlier editions) and Ricklefs (1993).

    Stevenson -6- Avian Behavioral Ecology


    Anti-predator behavior is avoidance behavior toward predators of all classes of animals based on species size: small species tend to forage, roost, and breed near or in foliage, middle-sized birds like American Crows (Corvus brachyrhynchos) tend to go to woody
    foliage and also outmaneuver avian predators in flight, and larger birds like Common Ravens (Corvus corax) and gulls outmaneuver and the ravens will turn on aerial predators. There are exceptions to this observation for a lot of species. Perhaps the most exemplary is the White-throated Swift (Aeronautes saxatalis), which even escape the Peregrine Falcon (Falco peregrinus) out west (Lima, Steven L. 1993, Ecological and evolutionary perspectives on escape from predatory attack: a survey of North American birds, Wilson Bull. 105(1): 1-47.).

    Part 1. Foraging Patterns

    I observed American Robins (Turdus migratorius), n100, foraging for earthworms (Oligochaeta: Lumbricdae) on the suburban lawns of Cedar Beach Park in Allentown, Lehigh County, eastern-central Pennsylvania (40.5968N x –75.5124W), in 1992, in a small flock with Common Grackles (Quiscalus quiscula). Birds tended not to forage straighter and in shorter bouts after a successful encounter with prey (Mood’s Median Test, N=1, 2= 0.1, p= 0.05, df= 1). Birds also tended to turn less acute angles after a successful
    Stevenson -7- Avian Behavioral Ecology

    probe (median= 140; N=1, 2= 628.4, df= 1, p= 0.05). The mean angle degrees after a successful run was 134 (SE13, cv= 40%). The mean angle degrees after not catching a worm was also 134 (SE13, cv= 38%). The mean angle after a successful run was 141.7 (n= 16, SE11.7, cv= 33%). The mean angle between unsuccessful runs was 140.6 (n= 16, SE12.3, cv= 36%). Not all robins do this behavior (Sign Test, z= 10, p>
    0.09, N.S. (non-significant)), but the observation was not unique (z= 0, p= 0.01). However, Sign Tests are low-powered statistically.
    My next robin optimal foraging project at the following site (in Part 2) will involve this spring observing GUT with a stopwatch with microseconds, measuring time of foraging on micropatches of lawn before they give up and move between patches in four categories, individuals, pair-bonding pairs, small flocks ( 25 individuals), and large flocks ( 25 individuals), either due to predator presence or searching for more food. Summer breeding foraging dynamics may be different either in the incubation, nestling
    or fledgling stage. Also, worm catch (after detection) and beak handling times in microseconds will be recorded. At least thirty samples each of these two variables will be recorded: a Spearman’s R will be done if the two samples are even in number, a Mann-Whitney U if uneven. Seed handling time in finches (Darwin’s Finches; Abbot, I., et al, 1975, Seed selection and handling ability of four species of Darwin’s Finches, Condor 77: 332-335; Grant, P.R., 1986, Ecology and evolution of Darwin’s Finches, Princeton University Press, Princeton, New Jersey.) and North American selected Fringillidae and Emberizidae finches (Willson, M.F., 1971, Seed selection in some North American
    Stevenson -8- Avian Behavioral Ecology

    finches, Condor 73: 415-429.). Dr. Willson examined fruit choices by robins (1994, Fruit choices by captive American Robins, Condor 96(2): 494-502.), but an average worm handling time has not been calculated, to the best of my knowledge. The average earthworm weighs about [0.2g] and is not “chewed” buy the upper and lower mandibles,
    but the head is tilted back and the item swallowed whole, thus a thin beak (shallow depth). A rule to all evolutionary biology is: “form fits function”.

    Part 2. Avoiding Predation

    Anti-predator behavior is staying next to foliage while ground foraging, say J.O. Oyugi and J.S. Brown (2003, Giving up densities and habitat preferences of European Starlings and American Robins, Condor 105(1): 130-135.). But Lima (1993) points out they
    often seen, including by me, singularly to large flocks in the middle of lawns. Why? Evolution should have an answer. I observed foraging spring and fall flocks since 1994 at the grounds of the Allentown State Hospital (ASH), Allentown, Lehigh County, Pennsylvania (40.6151N x –75.4293W), where, because I am on the Board of Trustees, the administration and security has so graciously allowed me to use it as a study site (Acknowledgements: Gregory Smith, President and CEO, and Ms. Tiffany Hudock, Administrative Assistant to Mr. Smith). The robin alarm note is a species-specific signal that is barely audible to the human ear (See: Caldwell, G.S. 1986, Predation as a selective force on foraging herons: effects of plumage color and flocking, The Auk 103: 494-505.).
    Stevenson -9- Avian Behavioral Ecology

    So I will purchase a Radio Shack or Sears sensitive pocket cassette recorder, or go on Ebay and see if they have plastic parabolic reflectors attached to amplified microphones attached to sensitive playback pocket recorders capable of making and playing continuous loop tapes or CDs. I saw flocks get up and shift places, a kind of “following-the-leader” to new found food patch or in response to human movement, but when they flew completely away, they seemed to be often with American Crows or European Starlings (Sturnus vulgaris), and
    possibly Common Grackles and Red-winged Blackbirds (Agelaius phoeniceus), and even more remotely so, Brewer’s (Euphagus cyanocephalus) and Rusty (Euphagus carolinus) Blackbirds. (There was the chance for a rare Emberizine or House Sparrow (Plocidae: Passer domesticus), but I only remember a Grasshopper Sparrow (Ammadramus savannarum)-call in a field full of Red-wings, that was a filled-in wetland, in another part of the property. Please see that ASH is in the suburban buffer zone between Allentown and Bethlehem. I may start a spring hawkwatch there because it overlooks the Lehigh River and I’ve observed quite a bit of raptor migration activity from there (fortunately
    the governor and state senate appointed me to the board there twice, making it Grant’s little private bird preserve with Mr. Smith’s kind permission.) Were they responding to cues, visual or auditory, from the other species? Or could the warn themselves? If so, was it with visual or auditory signals, or both? How did they react towards an avian or mammalian predator? Did they ignore them for a time? How long? (Predator Presence

    Stevenson -10- Avian Behavioral Ecology

    Tolerance (PPT)- my term- defined by time of ignorance, per separate taxa of predator, including hominid).

    AMERICAN CROW

    Part 1. Optimal Cooperative Feeding

    I define optimal cooperative feeding in American Crows as the mutual use of sentinels as predator guards while others feed below, then after awhile they switch off, and the sentinels feed. It is optimal because all individuals get to feed while not worrying about “looking up” for predators, optimizing energy intake. European Starlings do it (), and an observer of Canada Geese (Branta canadensis) told me he feels a drake always watches for predators in a flock at Cedar Beach: as he gets closer, it honks loudly and repeatedly and the flock moves away from the intruder.
    I have observed many instances of sentineling, but because I was going somewhere, I could not stick around for the switch-off. Sentineling in corvids is, though not well, documented. Lawrence Kilham observed this in only small groups (1989, The American Crow and Common Raven, Texas A&M University Press, College Station, TX.), but I have seen this behavior in mass winter roosts up to 50,000 birds (winter roosts have been observed up to 200,000 birds documented, they may go larger according to the carrying capacity of the habitat), the more birds on the ground, the more sentinels in trees. Winter roosts travel up to 81 kilometers a day in search of food (Terres, J.K., 1980, The Audubon encyclopedia of North American birds, Alfred A. Knopf, New York.). This is because Optimal Foraging Theory says once at a foraging habitat patch, it is the Law of Diminishing Returns. Eventually, it is worth the energy expenditure to travel elsewhere.

    I have seen cooperative feeding in crows personally only once according to my mutualism definition because of my itinerant schedule. It occurred at a street in front of
    2/21/06 -10- Common Bird Behavior

    Cedar Crest College, on the southern border of Cedar Beach Park in Allentown. It involved only two crows, possibly cooperatively breeding yearlings from a nearby nest attended to by the parental pair. Both took turns sentineling and and feeding in the road for ten minutes per bout, sentineling from approximately the same distance and height, feeding on what I hypothesize to be road-cracked acorns. American Crows () and Japanese Jungle Crows (Corvus macrorhynchos japonensis) in Tokyo () have been shown to use automobiles as nutcrackers, as tools, including American Crows with walnuts (Juglans spps.; Black Walnut Juglans nigra). A Sign Test calculated that the probability of all American Crows cooperatively feed, by my definition and sample, is 99%, very significant (z= 1.41, p= 0.01).
    4:10 am
    Off-spring Paper on Raptors
    LETTERS




    OFFSPRING SIZE DETERMINANT FOR K AND R-SELECTION IN FALCONIFORM BIRDS



    I define “intended offspring” as either data for clutch size or fledgling size per each nest, successful or not, averaged here from samples in the literature and nest cards.
    Knowing intended offspring of all falconiforms for this analysis was statistically unnecessary according to the opinion of a professional statistician this amateur consulted (Root pers. com.). I used study samples from nine species in The Birds of North America life histories. Many measures of spread (standard deviations or errors) were left out of BNA samples. It is necessary to know how data is distributed to be useful. So I assumed that BNA editors were unable to provide spread for all their data. That way I was able to obtain a "sizable" amount of samples. An even sample was deemed unnecessary by the consultant because it would "even out". It seemed to. A large sample is unnecessary because the relationship of raptor mass to intended offspring is generally consistent throughout the order, and in all birds, according to leading definitions of K and r-selection. I used survivorship curve definitions of K and r-selection from Klem (pers. com.), Horn and Rubenstein (1984, in Krebs, J.R., and Davies, N.B., Behavioural ecology: an evolutionary approach, Second Ed., Blackwell Scientific Publications, Oxford, U.K.), Pianka (1970, On r- and K-selection, The American Naturalist, June: 592-597), and Newton (1979, The population ecology of raptors, Buteo Books, Vermillion SD U.S.A). Included in all definitions were, for K-selection, large size and few young, and for r-selection, small size and many young. My hypothesis was the index between K and r-selection in raptors is a number of about three intended offspring.
    From encyclopedias and handbooks, I calculated average brood size for 33 North American species to be 1.5 (SE 0.05) based on a 154 d average breeding period.
    I arbitrarily selected the species means because in the final analysis the selection mean should not differ too much from how the species means were selected, or if all diurnal raptor species means (Root pers. comm.). I took "the mean of the means" because even though an even, gradual right-climb in the plotted data, it wasn't abrupt enough to use medians. The means were Golden Eagle (/x= 0.3, nest cards), Northern Goshawk (/x= 1.8, Reynolds et al 1994, Nest productivity, fidelity, and spacing of northern goshawks in northern Arizona, Stud. Avian Biol. 16: 106-133), Red-shouldered Hawk (/x= 2.7, Wiley, J.W. 1995, The nesting and reproductive success of Red-tailed Hawks and Red-shouldered Hawks in Orange County, California, 1973, Condor 77: 133-139), Cooper's Hawk (/x= 2.8, Craighead, J.J., and F.C. Craighead 1956, Hawks, owls, and wildlife, Stackpole Co. and Wildlife Management Institute, New York), Harris' Hawk (/x= 3, Bednarz, J.C. 1995, Harris' Hawk (Parabuteo uncinctus), The Birds of North America, No. 146 (A. Poole and F. Gill, eds.), The Academy of Natural Science, Philadelphia, PA, and The American Ornithologists Union, Washington, D.C.), White-tailed Kite (/x= 3.2, Dixon, J.B. et al 1957, Natural history of the White-tailed Kite in San Diego County, California, The Condor 59: 156-165), Ferruginous Hawk (/x= 3.7, Smith, D.G., et al 1981, Relationships between jackrabbit abundance and Ferruginous Hawk reproduction, The Condor 83: 52-56), Peregrine Falcon (/x= 3.7, White, C.M., et al 2002, Peregrine Falcon (Falco peregrinus), The Birds of North America Online (A. Poole, Ed.) Ithaca: Cornell Laboratory of Ornithology; Retrieved from The Birds of North America Online database: http://bna.birds.cornell.edu/BNA/account/Peregrine_Falcon/), Sharp-shinned Hawk (/x= 4.5, Bilstein, K.L., and K. Meyer 2000, Sharp-shinned Hawk (Accipiter striatus). In The Birds of North America, No. 484 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.), and American Kestrel (/x= 4.6, Smallwood, J.A., and D.M. Bird 2002, American Kestrel (Falco sparverius). In The Birds of North America, No. 602 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.). The mean is 3.03 (n= 10, /x= 3.03, SE+- 0.40). The mean is not significantly variant from the estimate (hypothesis). Because of the low-powered, random sample, a type II error may have been committed. My estimate was the number of intended off-spring between r and k-selection is a clutch of approximately +/- 3 eggs.
    Various teachers helped me with this calculation, including R. Root, C. Farmer, J. Lowe for nest cards, J. Schmutz, and A. Kemp. -Grant Stevenson, Open Space
    4:04 am
    FIELD NOTES FROM THE LIT


    The winter coming is the time for wax-eating yellow-rumps in Christmas Bird Counts. But in an 1992 paper (Place and Stiles 109:(2): 334-345), yellow-rumps and Pine Warblers both eat fruit like poison ivy and bayberry and waxy fruit (Myricia). Yellow-rumps have always migrated, along with phoebes, so late, that most birders now consider them all-winter possibilities, as the research, and CBC's demonstrate. One study (Wilz and Giampa 1978) studied them at Presque Isle and asked: why do these species overwinter so far north? They concluded, finding a mostly bayberry diet, the same thing Place and Stiles did, but added spider eggs. In both studies, Tree Swallows and flickers were mentioned as wax eaters which migrated, I assume, late.Going back to the archive of PB at Lehigh University, counts and less formal sightings have definitely fit these truisms.
    I remember my first CBC finding a catbird. Root (1988) published in the journal Biogeography and also in Ecology how energy metabolism (energetics) and the environmental factors of elevation, frost-free periods, latitude, vegetation, mean annual precipitation, general humidity, and minimum January temperature brought surprising lingerers at that time of such as kinglets, Sedge, House and Marsh Wrens, Brown Thrasher, and both vultures. For example, ambient temperature and elevation tend to affect the winter distrabution of Bonapartes Gulls the most, placing them on large lakes that tend not to freeze over. Now concentrating on the effects of global warming on bird species distributions (www.abcbirds.org), Dr. Terry Root has found that ducks that use prairie potholes, such as some species which the perhaps mostly first year individuals “loop” migrate back in the spring via PA, if non-raptorial (diurnal) birds do so (from Bildstein 2006 in respect to diurnal raptors), are threatened in North America and Australia due to drying of the landscape.
    4:00 am
    Hairies and Downies
    COMPARATIVE HABITAT ECOLOGY OF TWO SYMPATRIC PARKLAND WOODPECKERS

    Grant Stevenson 1, 2


    ABSTRACT.- Birdwatchers learn that to find Hairy Woodpeckers (Picoides villosus) it is getting easier since the 1992 Audubon designation of a Species of Special Concern, due to private farm reversion to woods and the maturing of exurban woods in parkland and woodland near water. Downy Woodpeckers still predominanently inhabit dryer secondary successional woods also, but denser with less mature stems (shorter trees with smaller DBH circumferences). The issue of better woodpecker management as cavity nester conservation is discussed, especially the need for de-emphasizing even-aged timber management.

    Key Words: Downy Woodpecker (Picoides pubescens), Hairy Woodpecker (Picoides villosus), nest cards, cavity nesters, even-aged timber management.
    3:57 am
    Coop behavior in General
    Cooperative behavior: what makes it so, and what makes it simply a blip in the natural history spectrum?- Cooperative breeding and what makes it so is definitive, or is it? Skutch (1987) cited many instances where the fact that cooperative breeding, and kin selection, occurred, or did it? As long as some genetic co-transference occurs down, technically there is cooperation. A cooperative animal operation by definition should contain as much relatedness between individuals as possible, though technically mechanical operations devoid of such inclusiveness are possible, especially of the mutual kind, like American White Pelicans schooling fish (Cottam, C. et al 1942), American Crows feeding on car-crushed acorns (my one observation/ idea), and even broadwings seeing prey cooperatively while in flock, and of course Harris' Hawks cooperatively hunting (more like mammals pack-hunting). Animals exploit the presence and actions of others, but the passing down of genotypes does not occur.
    There may be related individuals within a flock, but "wholeness" is a prerequisite for cooperation. Chimney Swift helpers were even termed only as "visitors", in a sense "floating helpers" (Dexter 1995). No inclusiveness occurred, no helping to the point of the passing of related genotypes. Visitors had the least amount of relatedness of many cooperative species. Evolution bumped on the parking lot slow bumper.
    Perhaps this is not about relatedness, like Emlem's bee eaters, but mutual fitness, and the almost pure altruism necessary to bring it out, and evolutionary bizarreness?
    I have no proof, just speculation, a one species, which makes these theoretical meanderings doubtful, and highly. It is clear to me, without scientific proof, that Dexter at least sometimes separated "visitors" from "helpers", but more literally than scientifically. Indeed, "visitors" and "helpers-at-the-nest" have been reported for a number of species (Woolfenden 1976).
    I digressed wholly and apologize. I am a fifteen-year amateur, and should be spending my time with natural history and field observation, not out of my league with theory. Yet one can learn from flopping around inside it. I hope the audience was patient, and may even reply so I can learn a lesson or two.- GRANT STEVENSON, Open Space
    Consultants, 946 Seneca Street, Suite 11, Bethlehem, PA 18015 (email: pahawkowl@yahoo.com)

    LITERATURE CITED


    COTTHAM, C. et al. 1942. The cooperative feeding of White Pelicans. Auk 59(3): 444-445.

    DEXTER, R.W. 1992. Sociality of Chimney Swifts (Chaetura pelagica) nesting in a colony.
    North American Bird Bander 17(2): 61-64.

    SKUTCH, A.F. 1987. Helpers at birds' nests: a worldwide survey of cooperative breeding and related behavior. University of Iowa Press, Iowa City.





    WOOLFENDEN, G. 1976.
    3:53 am
    Coop breeding in Corvidae
    RUNDOWN ON COOPERATIVE NESTING IN AMERICA BY CORVIDS


    Corvids- like us- are social. Even though there are ornithological papers saying that American Crows use cars as nutcrackers and do not, they are cooperative feeders, using sentinels too look out as others feed on the ground, and as cooperative breeders, territory members share information to show each other where the grub is. Common Ravens do the same, as perhaps other raven and crow species.
    But there are other north American corvids that cooperatively breed, maybe feed, and “flock”, a social behavior which enables social protection and more eyes to see a limited or ecologically constrained resource like food or potential nest sites. Like in ravens, they are organized by a “peck” dominated male and female, sometimes in a hierarchy, though in ravens it is not progressive. At a carrion “bonanza”, the two birds have the other adults and juveniles under them and they feed when they want to eat.

    Brown Jay

    Green Jay

    Florida Scrub Jay

    Pinyon Jay

    Mexican Jay

    Tufted Jay

    Northwestern Crow- very few helpers per nest

    These species are also notorious flockers. Dr. Stephen T. Emlen of Cornell examined 112 bird species and 63 mammal species and found that 96% of avian species and 90% of mammal species demonstrate cooperative breeding. Cooperative breeding, he said, is primarily restricted to familial societies.
    He found that 88% of the birds and 95% of the mammals are cooperative breeders living in multigenerational family groups.

    Blue Jays.- Are hard to keep up with enough to indicate coop anything, though breeding pairs can hold onto territories all year round. There was one MS thesis indicating observance of helping, but it did not go anywhere.
    Cooperative breeding is defined as pairs helped by familials such as previous off-spring while passing on only 50% of their genes, with the hope of gaining the parental territory to breed in in the future upon the deaths of the dominant parents. Cooperative feeding, named after Eurasian and American White Pelicans learned to coral fish using a cooperative closing circle (and peripheral single feeders have more luck!), can mean a lot in corvids, like flocking daily winter night (I.e. crows) and day (I.e. Pinyon Jays) roosts and the use of sentinels (which starlings and Canada Geese do, too) and is defined as comensually (one side profits, the hunted does not, as opposed to mutualism and parasitism). Sociality is expressed in many behaviors such as flocking.
    3:50 am
    American Crow Behavior
    LETTER


    Dear Corvi's:

    My handwriting caused the Chronicle to inadvertently spell my handle incorrectly: it's C. frugivorus Bartram. However, I thought since of a better solution. From now on I'm Corvi 2.58 (I'll try another number if already taken.). Unless you are a professional or amateur statistician, the number has no significance. It's the z distribution number that indicates p= 0.05, often times the minimal acceptable probability (95%) for a behavior, number, etc., but in ecology less significant probabilities are accepted because of field realities (Wiens, J.A., The ecology of bird communities,).
    Our crow literature, whether a good library book or the published scientific literature, says that American Crows (Corvus brachyrhynchos) and Jungle Crows (Corvus macrorhynchos), and perhaps other species, like urban human refuse most as a food source, then invertebrates, including those in urban and suburban lawns. Even though both are originally forest species, they have hyperadapted to the smorgasbords left by humans and the breeding predator safety of their neighborhoods. Crow cultural innovation, because Corvidae brains have one of the highest brain masses to body mass ratios of all birds (Reckless, R.E., Wilson Bulletin 116(2): 119-133 (2004)), has caused a commensally (one species gains while the other doesn't) symbiotic feeding relationship between crows, other corvids, and humans. The Gray Jay since Thoreau's time and earlier has been known as "the picnic and campsite robber", often quickly snatching food like bacon right out of hands when humans are not looking, which takes timing and learned skill. They also have learned to be a passenger on the bow tips of canoes.
    Making the garbage more sanitary will not necessarily decrease roosts because crow culture is fast to innovate toward another hominid food source. Killing members of a roost will definitely not work because of supply and demand, ecology, and population demography rules. In other words, over the long-term, healthy remaining crows will take advantage of the more available food and other resources and reproduce more.

    Corvi #2.58 -2- Letter: Corvus Smarts


    Lastly, I am investigating the hypothesis that American Crows display occasionally not only cooperative breeding, but COOPERATING FEEDING. Selective feeding already has been documented. Crows, for example, as proven by the eight year old son of John Marzluff, prominent world crow biologist at the University of Washington, readily distinguish McDonald's fries in a McDonald's bag from fried potatoes made at home in an unmarked bag, only a few meters away, preferring Mickey Dee's fat-soaked fries that a substantial portion of us like so much. I define cooperative feeding in crows as "mutual". In other words,
    when a sentinel comes down from a perch to feed in the group, at least one from the ground ascends to replace it, senteneling "in exchange". Feed corn, or cracked corn from the grocery store, will be used, maybe even a dead deer in a local refuge. I have a spot right outside my window all year long in Bethlehem if the police cooperate. I am asking any and all Corvi's to contribute observations to the project, however opportunistic, at the below address. All that needs to be said is "coop. feeding observed, X no. of times [even if once], in [urban, suburban, exurban, rural] setting" and your true name if you wish to be acknowledged in the journal article, on a postcard, if you wish. Or you can contact me at any of the below unless you wish to remain anonymous. Thank you very much!!

    Corvi #2.58
    Director and 14-Yr. Amateur Ornithologist
    Open Space Consultants
    946 Seneca Street, Suite 11
    Bethlehem, PA 18015
    Phn 610-867-2862
    Fax 610-866-6234, call first
    Em Surnia_ulula_caparoch@verizon.net
    Amateur ornithology research URL, PAHawkowl: http://pahawkowl.livejournal.com
    Sunday, July 10th, 2011
    4:53 pm
    The Grinnell Journal
    Arrogant Amateur: Statistics and 17 Years of The Grinnell System As A Long-Term Study


    Grant Stevenson


    The Joseph Grinnell style avian daily and species journal has many applications, and contrary to popular professional belief lends itself to rigorous statistical data analysis. The goal here is to give one example of a species account from the daily birding entries, for the American Crow (Corvus brachrychos) and analyze them for time-series analysis and unique center and spread techniques non-traditional in ornithology: the stem plot and quantile analysis. Simplification of technique is emphasized, including the advantage of simple descriptive statistics such as frequency polygons. One of my main theses is that the most simple presentation of data is preferred over sophisticated, but unnecessary methods. Finally, I prove fairly that a lot of professional ornithologists do not apply correct analysis (Moore and McCabe 2003), as a lot of professional statisticians do not know the limits, most variables, and field reality of biostatistics (Zar 1997; Wiens 1989). For example of the latter, Wiens (1989) states that in field avian community ecology there are so many variables that a p-value of <0.15 is acceptable. Applied to long-term data bases such as more than ten years of journaling of a variety of different habitats and species, which for one person is significant, I use my crow species account from 1995 to 2008 to illustrate what applications can be made, plus a word about the global warming value of the method, and how a hard copy is always preferrable in the long-term to websites and software, lest the system shuts down or brakes, possibly destrying your data forever. The Grinnell journal thus is a predessesor to eBird and Avisys, etc. Back tracking, only two variables are worthy of consideration, space and time (Wiens 1989), which is not as easy as thought in a census model, such as the all important local life history/nesting studies or local, weekly Resident Bird Counts. First though, I present how the Grinnell Method of natural history journaling is done.

    History foundation.- Joseph Grinnell, not to be confused with the earlier personage of George Bird Grinnell of the Smithsonian Institution, a contemporary colleague of James Baird, was a professor in the University of California Museum of Vertebrates at Berkley in the early twentieth century, not to be confused with the current Western Foundation of Vertebrate Zoology. He, with ornithologists like J. V. Remsen, Sr., determined an ecological method to record natural history observations, from birds to botany. Trained as a mammal and avian morphological taxonomist, he realized the need for a standardized method of wildlife observation recording.

    Example of Daily and Species Accounts.- Remsen, Jr. (1977), Herman (1986), and Kress () well describe simply how to do a Grinnell system of field notes. Carry a memo book always with you, writing the date and times, species lists within those times, and write in pencil because it is erasable and does not blurr in the rain. Write-in-the-Rain field books are an expensive, and not necessary, alternative. A simple surveyer's book is useful for more elaberate field projects.
    4:50 pm
    The Wood Thrush in Lehigh Valley, PA
    FIELD NOTE




    Subject: Urban Woodlot Size Use by Singing Wood Thrush (H.O.), Lehigh Valley, Pennsylvania, 1996-2005

    Key: small lot: 1-5 acres, medium lot: 5-25 acres, large lot: 25-50 acres.

    Summary: Individuals per journal entry= 4.4, n= 10 days, SE+/- 1.4. Total birds (Wood Thrush)= N= 44. Total hours= 3.75 hours. Turnover= 0.9 individuals. Q1= small, m= median, Q3= large, n= lots (10). This data was ad hoc: not consistent, systematic, or carefully recorded for any study (from a Grinnell field journal). Thus any regression graph is meaningless. For example, the linear r2 for this data is 0.006, insignificant (n= 119). Lot sizes were small, 10%, medium, 50%, and large 40%, n= 10 days. IQR= Q3-Q1= 40%. Quantile analysis is one of the simplest, most effective ways to show center and spread.

    Discussion: One can only surmise from this analysis that Wood Thrush can sometimes prefer medium sized lots to larger ones in urban and suburban situations, but the limited data renders only a working hypothesis.
    Research on urban habitats need to be included into Citizen Scientific projects regarding forest thrushes.
    Between 1966 and 1978, Wood Thrush increased by 1.3 percent per year, and decreased by 4.0 percent per year 1978-1987. Overall, to the present, we've seen a decrease by about 3.5 percent per year 1966-1996 (Robbins et al 1989). The bird is on the Pennsylvanian Audubon Watchlist. The state designates it as a Species of Special Conservation Concern.

    -Grant Stevenson, Fountain Hill, PA, pahawkowl@yahoo.com, http://pahawkowl.livejournal.com.

    HELPFUL INFORMATION

    Bart, Jonathan, and J.D. Schoultz. 1984. Reliability of singing bird surveys: changes in observer efficiency with avian density. Auk 101: 307-318.

    Hunter, J.E., and R. LeValley. 1996. Improving the reliability of Marbled Murrelet surveys in low abundance areas. Pacific Seabirds 23(1): 3-4.

    Robbins, C.S., et al. 1989. Population declines in North American birds that migrate to the neotropics. Proc. Natl. Acad. Sci. 86: 7658-7662.

    Wiens, J.A. 1981. Single-sample surveys of communities: are the revealed patterns real? Am. Nat. 117: 90-98.
    4:41 pm
    AFO Afield
    Dr. Kim Young, Editor


    Proposed Society Effort to Reestablish the Bird Counts Program

    By Grant Stevenson, Open Space Consultants


    I believe the Breeding Bird Census (BBC) and Winter Bird Population Study (WBPS) should be reestablished at the Cornell Lab of Ornithology online, with a paper option on standardized forms, with a funding search committee headed by the AFO and possibly other societies.
    The reasons for a Bird Count Program are the usual, multiple, and legitimate ones. Besides being good studies of island biogeography, or at least the best amateur ones to date (and I'm open to ornithologists' alternatives), the wording in a paper by Robert E. Ricklefs, "The metapopulation: a model of demographic coupling between migrant and resident landbird populations" (1992), summed it up well (taken out of context). We need better information on population densities of all habitats, which are changing due to global warming, etc., productivity, and prebreeding and adult survival, especially in the tropics, where long-term studies of marked populations are lacking compared to North America, due to fewer resources.
    We can start recording other parameters not on the traditional forms to give ornithologists more information to work with. One would be the presence of avian and mammalian egg predators. Others would be accipiter and other adult songbird predators, brood parasites, owl counts, and other ecological factors not covered by the Breeding Bird Survey (BBS).
    Terry Root observed in the journal Nature that in order to monitor populations on a more than local scale professionals must "enlist an army" of Citizen Scientists to gather the data. I believe it is not a chore but an opportunity to participate in something really significant and useful to bird conservation.
    I proposed a resolution before the AFO, which if accepted by Council and the Board will go before the society at the NAOC (I will not make it there for personal reasons.). In it, I proposed resurgence over time of the Bird Count Program, with structure and funding to be determined later as opportunity exists. I simply want first the concept to be accepted in spirit first as a first step.
    I want to thank Jim Lowe and Sam Droege for keeping the long-term bird counts concept alive in the aftermath of their official demise. If one wants to do a long-term BBC or WBPS, one still can. Simply ask Jim for the forms (jdl6@cornell.edu) and send them each year upon completion to Sam (sam_droege@usgs.gov). To discuss my proposal and a copy of the resolution, send me email at surnia_ulula_caparoch@verizon.net.
    Saturday, July 2nd, 2011
    4:28 pm
    This May Have Been In THE BIRD OBSERVER As Well
    FIELD NOTE




    Eastern Wood-Pewee behavior field note, Emmaus, PA (40.539DEG N X -75.497DEG W; 448 ft.). - A pair of Eastern Pewees (Contopus virens) hawked, or seemed to hawk, "aerial plankton", aerial insects a backyard together beneath the wooded South Mountain of The Highlands, the New England Physiographic Province. They sang, and anti-phonally with another pair, which may be late in the season for this species (Fisler 1962).
    On September 2, 2006, Tropical Storm Ernesto's cyclones hit this area. Even in the wind and downpour, they continued hawking. Two explanations are possible, among possible others. One, there were insects in the air even during these conditions, and two, the two birds were exhibiting a behavior called "vacuum activity". McClure (1938) tested aerial insect population activity all-year long and found activity during cloudy as well as clear weather except in January, when there was none. He did not mention activity during precipitation. Vacuum activity is normal activity when there is no stimulus, like available food, to otherwise stimulate the behavior. It is a fixed action pattern, inherited, where an animal has no stimuli, but energy builds up anyways, and the behavior is expressed. House cats do this because much of their behavior is innate, but without the original, evolutionary stimuli available to appropriately express it to, like stalking and pouncing. -Grant Stevenson, Open Space Consultants, 946 Seneca Street, Suite 11, Bethlehem, PA 18015.

    Literature Cited

    Fisler, G.F. 1962. Variation in the morning awakening time of some birds in south-central Michigan. The Condor 64: 184-198.

    McClure, H.E. 1938. Insect aerial populations. Annals Entomological Society of America Vol. XXXI: 504-513.
    Friday, July 1st, 2011
    5:39 am
    NESTING ECOLOGY AND NICHE IN TWO SYMPATRIC WOODPECKERS





    Introduction.- The Cornell Lab of Ornithology’s North American
    Nest-Record Card Program still provides auxiliary field data for amateur nest studies. They can still provide information for analysis on nesting biology and ecology, and density-dependent and density-independent mortality causes. Some distribution and perhaps quasi-time series trend analysis of breeding of species can possibly be cautiously extrapolated. For an analysis of the history and potential biases of the use of the cards in a study, see Peakall (1970).
    I examined two sympatric species common and related (by genus) woodpeckers, which seem to have a lot of ecological traits in common, though on slightly different scales due to different body masses. The Competitive Exclusion Principle of Joseph Grinnell states that that no two species can occupy the same niche. The sum total of characteristics of the species, a niche is the ecological role of a species in a community; the many ranges of conditions and resource qualities within which the organism of species persists, often conceived as multidimensional space (Ricklefs 1993), as determined by its life history. Cornell nest card data for these two woodpeckers corroborated that theory except for piecemeal similarities in life history data. The Downy Woodpecker (Picoides pubescens) is 17.2 cm in length and has the mass of 27.0 grams, while the Hairy Woodpecker (Picoides villosus) 23.8 cm and weighs a sexually dimorphic 70.0 (male)and 62.5 grams (female) (Dunning 1993). The differences between the birds’ lengths and weights are significant (p=0.05). Their territory sizes differ proportionately, but non-significantly (p=0.05), about 15 acres for Downy Woodpeckers and about 20 acres for Hairy Woodpeckers.
    I examined data from all cards from Michigan, Ohio, Kentucky, West Virginia, Virginia, Maryland, Pennsylvania, New York, New Jersey, Delaware, Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire, Maine, and Southeast Canada from 1920-1998 for Downy Woodpeckers and 1908-1998 for Hairy Woodpeckers. This study and those like it could help timber managers managing woodpecker habitat. Tree excavators and cavity nesters have greater difficulty optimizing changes in forest structure, and in the long-term we cannot afford to engage in too much snag removal, even-aged timber management, and and infra-structure development, or “sprawl”, without better woodpecker management (Pinkowski 1976?). The Southeastern American Kestrel subspecies’s (Falco sparverius paulus) nest hole availability is correlated with Red-cockaded Woodpecker (Picoides borealis) abundance, the holes of which were enlarged further by other Picidae (Gault et al 2004). Therefore, more research, bird counts, atlases, and other bird conservation efforts are imperative for all avifaunal species diversity management and the mitigation of human impacts.

    Results.- Downy Woodpeckers (N=240 cards) had 43 (17.9%) urban/suburban cards, 10 (23.3% ) of which were urban. In wooded areas, 56 (23.3%) were of mixed, including one in a mixed Christmas tree farm, and 87 (36.3%) were of deciduous, including one in a solitary tree near a woodlot and one along a canal. Two were of coniferous (0.8%), both in Nova Scotia, 1 (0.4%) in a flooded deciduous environment, and 1 was in an orchard (0.4%). Eleven cards were near fresh water (4.6%), and 13 were near swamps and marshes, more marshes (5.4%). Trees in grasslands accounted for 5 cards (2.1%) on wooded islands, and near hedgerows, windbreaks, an orchard, and were deciduous. Fields accounted for 4 cards (1.7%), including a nest on a walnut tree (Juglans spps.) and in limbs of hawthorne (Crataegus spps.) and one on a White Ash limb (Fraxinus americana). Ecotone (edges of fields, woods, and roads) accounted for 5 (2.1%), fallow field trees for 5 (2.1%), cultivated field trees for 2 (0.8%), and shore edges for 1 (0.4%).
    Downy Woodpeckers had 36 nests with some success (n=150 cards, 1920-1998) with a median height of 76.0 m (range 15.2-285.0 m, /x= 93.4 m, SD+- 71.4 m, cv= 76.5%). Any coefficient of variation (cv) above 50% shows significant nest-to-nest variation in height.

    171-285 m ___5.0%

    121-160 m ______9.5%

    81-120 m _____________19.8%

    41-80 m _______________________________43.9%

    0-40 m __________________21.8% ________________________________________________________________________

    Nest No. 0 10 20 30 40 50

    Downer Woodpeckers prefer midstory by more than chance alone (x2= 17.6, p= 0.05, df=6).
    Hairy Woodpeckers habitats (n=160 cards), 1908-1998, broke down like this: 6 (3.8%) urban, 5 (3.1%) suburban, mixed woods 50 (31.3%), deciduous 70 (43.8%), coniferous 1 (0.6%), orchard 2 (1.3%), fresh-water swamp 13 (8.0%), near fresh water 6 (3.8%), Ecotone (edge of field, woods, paved surfaces, etc.) 5 (3.1%), near cultivated fields 1 (0.6%), and near a fallow field 1 (0.6%).
    Hairy Woodpeckers had a nest height of /x= 8.1 m (range of 1.22 m – 24.40 m, SD+- 4.2 m, median= 7.62 m, n= 152 cards, cv= 51.9%).

    20+ m _____1.3%

    15-20 m ________5.9%

    10-15 m __________________________20.3%

    5-10 m _______________________________________________________45.0%

    0-5 m _________________________________27.5%

    ___________________________________________________________________

    0 10 20 30 40 50

    Hairy Woodpeckers in this sample preferred the understory by more than chance alone (x2= 69.8, p=0.05, df= 2).
    Discussion.- My results corroborate the widely held belief by amateur birders of the niche- and thus dietary- overlap and partitioning by these similar, yet distinct, sympatric woodpeckers confirmed in Connor and Adkisson (1977), Swallow et al (1988), and McFarlane (1992), and comparatively treated with respect to crossbills (Loxia spps.) in Benkman (1987). Downy Woodpeckers prefer higher limbs and the trunk for foraging, and may be more likely to drill nest holes in branches. Females prefer the trunks while males prefer the upper branches in sexual niche partitioning (Grubb). Woodpeckers select as a hole, however, to nest on older, more mature snags than those they forage on (Swallow et al 1988). Bent (1939) determined the nest height of the “Eastern “ Hairy Woodpecker to be 5 to 30 feet high
    and found 6 in dry upland woods, 2 in maple swamps, 3 in apple orchards, and 1 in a small Red Maple in a swampy meadow away from any other trees. Four were in dead trees or branches, the rest in living hardwoods. The “Northern” Downy Woodpecker’s haunts were described by Bent as a branch or snag 8 to 50 feet , dead or dying, or at times live. Brenner et al (1992) described Downy haunts as 61.7% ecotone (n=350). Brauning (1992) cites orchards and riparian areas near developed areas and heavily wooded tracts, including coniferous forest for microhabitat, for Hairy Woodpeckers in Pennsylvania. One mature stand seems to be all that is required for continuous occupation. It described microhabitat for downies simply as all habitats with trees (Kaufman (1996). Both seem to prefer deciduous, especially oak-hickory, woods. As a matter of fact, Brauning and Kaufman’s descriptions of habitat and microhabitat for the two species are almost identical. I scoured the life histories, encyclopedias, field guides, and handbooks of North American birds, and two articles (Rundy and Capen 1987, and Connor et al 1994) and found that their descriptions similar to the 100 years of Cornell Lab nest-record cards. Nine related studies presented these habitat characteristics. Downy Woodpeckers foraged smaller diameter tree species and more diversity of them (Connor and Saez 19 ). Connor and Adkisson (1977) showed that Downy Woodpeckers prefer more dense and less mature stems than Hairy Woodpeckers in Principal Component Analysis (PCA) of the habitat requirements of five woodpecker species. Species tree selection may be determined by tree hardness by both woodpeckers (Schepps et al 1999). Intersexual niche partitioning is not recognizable on the predominance of cards, but see Williams (1980) and Peters and Grubb (1993).
    The Downy Woodpecker is by far the most numerous in Pennsylvania (McWilliams and Brauning 2000), being the smallest and less vulnerable to habitat fragmentation, and the most amenable to young woods. Hairy Woodpeckers depend in part on mature parkland near urban areas. Woodpecker adaptation to changes in habitat does occur over long periods by changes in niche and morphology (McFarlene 1992), but quick changes by means of spawl, air-born viruses, and weather disasters can bring on local extirpation. However, hurricanes and tornados fell more trees, causing more nesting and food opportunities
    (Jackson 2005).
    Glue and Boswell (1994) wrote the model for this study for the Green Woodpecker (Picus viridus), the Lesser Spotted Woodpecker (Dendrocopos minor), and the Greater Spotted Woodpecker (D. major), three sympatric, popular parkland birds on the British mainland. Their niches overlap, yet are also discrete. Though they occupy similar environs, they also found each species had separate microhabitat requirements, as did this study.
    Klem (pers. Comm.) stated that if every live tree in a suburb was a snag, it would rival the situation when the forest was before humans. Many species of northeastern birds and mammals depend on primary excavators. Suburbanization, in the forms of sprawl and woodlot development, hurt these two species, and thus their secondary occupants, as many species in part are limited by the availability of nest sites.
    The sympatric Downy and Hairy Woodpeckers are quintessential examples of woodpecker species that provide in northeastern U.S. and southeastern Canada unique homes for only the species of secondary nest users which occupy these bird's habitats, and more specifically, microhabitats. They seem partly niche discrete, however there is niche overlap, defined as the sharing of space by two or more species where there is similarity of resource requirement and tolerance of ecological conditions (Ricklefs 1993). Relative to their body lengths and masses, Hairy Woodpeckers tended to nest in the understory, in other words, the trunks of the trees, being able to maneuver around them with more ease, while Downy Woodpeckers preferred the midstory, often excavating in dead branches. Hairy Woodpeckers tended to nest in parkland in urban areas, with mature trees that are spaced apart, possibly preferring to be near water. Downy Woodpeckers, on the other hand, seemed to go for dryer, higher ground, sometimes in orchards but invariably in woodlots near edges that were denser in tree stems and lower in canopy height.
    I found the two species to follow the Competition Exclusion Principle on the microhabitat and habitat level, but because their habitats overlap in secondary successional woods, there was the reason for the niche overlap. Though McFarlane (1992) stated a woodpecker's niche is defined by its diet, other factors like territory size and habitat/micro-habitat may also be considered. I there were no place for diet information on the cards, but since there was habitat niche overlap, there could have been food niche overlap. But the literature demonstrates some unique differences in diet and therefore morphology, as McFarlane points out.
    My results agreed with seventeen years of observation of mine and more of other amateurs birdwatchers in Pennsylvania, due to excepted common knowledge. The results basically, with some variation, concurred with the Birds of North American life histories (Jackson and Ouellet 2002; Jackson, Ouellet, and Jackson 2002). It showed that each species of woodpecker has its own unique set of animals it provides homes to, and thus is important to the web of life in the study area.

    ACKNOWLEDGMENTS

    I thank foremost D. Glue and T. Boswell for their paper that acted as a model, based on British Trust for Ornithology nest cards for this paper BTO for their help. I thank D. Klem for allowing me the use of his library for much of the literature research. I thank a few anonymous reviewers for comments on an earlier draft of the manuscript. Finally, I thank Jim Lowe and the Cornell Lab of Ornithology and the authors of each of the Downy and Hairy Woodpecker nest cards of Cornell’s North American Nest-Record Card Program spanning the twentieth century.

    LITERATURE CITED

    Arsenault, D.P. 2004. Differentiating nest sites of primary and secondary cavity-nesting birds in New Mexico. J. Field Ornithol. 75 (3): 257-265.

    Baillie, S.R., and W.J. Peach. 1992. Population limitation in Palaearctic-African migrant passerines. Ibis 134 suppl. 1: 120-132.

    The Brookings Institution. 2003.Back to prosperity: a competitive agenda for renewing Pennsylvania. The Brookings Institution Center on Urban and Metropolitan Policy, Washington, D.C. www.brookings.edu/urban

    Bryant, A.A. 1986. Influence of selective logging on Red-shouldered Hawks, Buteo lineatus, in Waterloo Region, Ontario. Canadian Field-Naturalist 100 (4): 520-525.

    Blem, C.R. 1980. The energetics of migration. In: Animal migration, orientation, and navigation. Academic Press, Inc., San Diego, CA.

    Blem, C.R. 1990. Chapter two: avian energy storage. In: Current ornithology, vol. 7 (Edited by D.M. Power). Plenum Publishing Corporation, N.Y., N.Y.

    Castro, G., et al. Ecology and energetics of Sanderlings migrating to four latitudes. Ecology 73 (3): 833-844.

    Clarion Associates, Inc. 2000. The costs of sprawl in Pennsylvania: executive summary. 10,000 Friends of Pennsylvania, Inc., Philadelphia, PA.

    Connor, R.N., and C.S. Adkisson. 1977. Principal component analysis of woodpecker nesting habitat. Wil. Bull. 89 (1): 122-129.

    Dale, V.H., et al. 2000. ESA Report: ecological principles and guidelines for managing the use of land. Ecological Applications 10 (3): 639-670.

    Denworth, J.R. 2002. Planning beyond borders: a multi-municipal planning and implementation manual for Pennsylvania municipalities. 10,00 Friends of Pennsylvania, Inc., Philadelphia, PA.

    Dunning, J.B., Jr. 1993. CRC handbook of avian body masses. CRC Press, Ann Arbor, MI.

    Gault, K.E., et al. 2004. Nest success of Southeastern American Kestrels Associated with Red-cockaded Woodpeckers in old-growth Longleaf Pine habitat in northwest Florida. Southeastern Naturalist 3 (2): 191-204.

    Glue, D.E., and T. Boswell. Comparative nesting ecology of three British breeding woodpeckers. British Birds 87 (6): 253-269.

    Grubb, T.C., Jr. 1982. On sex-specific foraging behavior in the White-breasted Nuthatch. J. Field Ornithol. 53 (4): 305-314.

    Hamerstrom, F., et al. 1973. Nest boxes: an effective management tool for kestrels.

    Hazler, K.R. 2004. Mayfield logistic regression: a practical approach for analysis of nest survival. Auk 121 (3): 707-716.

    Jackson, J.A., and H.R. Ouellet. 2002. Downy Woodpecker (Picoides pubescens). In The Birds of North America, No. 613 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

    Jackson, J.A., H.R. Ouellet, and B.J.S. Jackson. 2002. Hairy Woodpecker (Picoides villosus). In The Birds of North America, No. 702 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

    Katzner, T., et al. 2005. Results from a long-term nest-box program for American Kestrels: implications for improved population monitoring and conservation. J. Field Ornithol. 76 (3): 217-318.

    Krebs, J.R. 1970. Regulation of numbers in the Great tit (Aves: Passerformes). J. Zool., Lond. 162: 317-333.

    Marti, C.D. 1994. Barn Owl reproduction: patterns and variation near the limit of the species distribution.

    McFarlane, R.W. 1992. A stillness in the pines: the ecology of the Red-cockaded Woodpecker. W.W. Norton and Company, N.Y., N.Y.

    Moyer, B. 2003. Pennsylvania’s wildlife and wild places: our outdoor heritage in peril. PA DCNR and Wild Resource Conservation Fund, Harrisburg, PA.

    National Geographic. 2000. Field guide to the birds of North America. Third Edition. National Geographic Society, Washington, D.C.

    Peters, W.D., and T.C. Grubb, Jr. 1983. An experimental analysis of sex-specific foraging in the Downy Woodpecker, Picoides pubescens. Ecology 64 (6): 1437-1443.

    Pinkowski, B.C. 1976. Use of tree cavities by nesting Eastern Bluebirds. J. Wildl. Manage. 40 (3): 556-563.

    Pravosudov, V.V. 1993. Breeding biology of the Eurasian Nuthatch in northeastern Siberia. Wil. Bull. 105 (3): 475-482.

    Ricklefs, R.E. 1980. Geographical variation in clutch size among passerine birds: Ashmole’s Hypothesis. Auk 97: 38-49.

    Rodewald, P.G., and M.C. Brittingham. 2004. Stopover habitats of landbirds during fall: use of edge-dominated and early-successional forests. Auk 121 (4): 1040-1055.

    Schlamadinger, W.B., and G. Marland. 2000. Forests and soils can play significant role in mitigating climate change. Pew Center on Global Climate Change of the Pew Trusts, Arlington, VA. Summary 3 pp. Contact: Dale or Vicki, 202-777-3530 and 703-516-4146, respectively; full report: www.pewclimate.org

    Schlamadinger, B., and G. Marland. 2000. Land use and global climate change: forests, land management, and the Kyoto Protocol. Pew Center on Global Climate Change of the Pew Trusts, Arlington, VA.

    Sibley, D.A. 2000. National Audubon Society: the Sibley guide to birds. Alfred A. Knopf, N.Y., N.Y.

    Sherry, T.W., and R.T. Holmes. 1995. Summer versus winter limitation of populations: what are the issues and what is the evidence? In: Ecology and management of Neotropical migratory birds: a synthesis and review of critical issues. (T.E. Martin and D.M. Finch, eds.). Oxford University Press, Oxford.

    Sherry, T.W., and R.T. Holmes. 1996. Winter habitat quality, population limitation, and conservation of Neotropical-Nearctic migrant birds. Ecology 77 (1): 36-48.


    Swallow, S.K. et al. 1988. Snag preferences of woodpeckers foraging in a northeastern hardwood forest. Wil. Bull. 100 (2): 236-246.

    Usher, M.B. 1966. A matrix approach to the management of renewable resources, with special reference to selection forests. J. Applied Ecol. 3: 355-367.

    Usher, M.B. 1973. Biological management and conservation. Chapman and Hall, London.
    4:12 am
    This may have been published in THE BIRD OBSERVER of the MASS. Audubon Soc.
    “STANDING” CHIMNEY SWIFTS

    GRANT STEVENSON 1,2


    Abstract. -On a late April morning, 1993, twelve Chimney Swifts (Chaetura pelagica) out of a flock of about thirty individuals were seen “standing” in a row in a straight line for about ten seconds in Allentown, Pennsylvania. Noticeable was their intent to flock and freeze (standing on their haunches) in anti-predatory behavior responding to two accipiter hawks chasing them. Given similar conditions, this behavior should be performable by all individuals of this species and order taxa. This represents the first published account of this behavior among Chimney Swifts, despite anecdotal references to the contrary.
    ______________________________________________________________________________________________________________________________

    The Chimney Swift (Chaetura pelagica) Birds of North America life history mentions only: “…seldom perches on a branch…”. The main author was reported to have said to this paper’s claim that Chimney Swifts cannot stand…it is morphologically impossible. He is right and he is wrong. Swifts standing I have found is unbelievable to ornithological and bird watching “doubters” as opposed to “believers”. As a consequence, “doubters” often miss out on ecological firsts and rare sightings, though a healthy dose of critique is important to the process.
    The feet of the Chimney Swift in the Bird Collection at Muhlenberg College, Allentown, Pennsylvania are curled around its perch, and swifts grab dead twigs off of tree crowns for nesting. This paper is possible evidence of “standing”, not perching. They were on their haunches, like “brooding hens”. There is a photo of this behavior in the White-throated Swift (Aeronautes saxatalis) on the front cover of its Birds of North America life history (Ryan and Collins 2000) and in the Common Swift (Apus apus- Lack 1956).
    Besides this quantified example, however small, is a local farmer of mine who claimed to see Chimney Swifts “stand” on clods of dirt in his fields, and the security man at the tower where my observation took place, who claimed the birds “stand [on the tower] all the time”!
    The Pennsylvania Power and Light Company (PPL) Tower is in Center City Allentown, 4036’30” x 7529’26”, at 134 m above sea level. The Tower is 103m high. Chimney Swifts at the time of the observation were frequent breeders in urban chimneys and heat ducts across the greater Lehigh Valley (including Bethlehem and Easton), east-central Pennsylvania. However, these premature roosts may be chimneys with single breeding pairs and up to 40 helpers-at-the-nest, or “seasonal visitors” (Dexter 1992; Cink and Collins 2002). Allentown is a small city surrounded by minimal well-established suburbs with parks, sprawl, and rural cultivation and open space.
    A flock of about thirty swifts at about 05:30 h on a late April day descended onto the flight space of the top of PPL Tower to feed on aerial insects in the tower’s floodlights. Dawn was rising. I was at the foot of the tower about ninety meters from the base, using 7x35 binoculars, with a clear view; it was overcast, but the clouds were high. There was no precipitation and the temperature was mild.
    Suddenly, a Cooper’s Hawk (Accipiter cooperii), and a little later a Northern Goshawk (Accipiter gentilis), arrived on the scene and chased after the swifts, perching intermittently. Twelve (40%) out of the thirty “froze”, side-by-side, in a line (minimum individual distance about 125mm;
    /x200mm), on top of a ledge, facing us (SE 0.091). The Confidence Interval (CI) was approximately 0.4 +- 0.18, 22% to 58%, probably closer to 22%, that swifts are capable to “standing”-like behavior, given similar situations (p=0.05). A Sign Test, a low-powered test, stated that the entire species exhibits this behavior, interpreted liberally (z= -1.10, p= 0.01). The birds remained frozen only for about ten seconds, and then continued to evade the hawks. Freezing may be a temporary and little used tactic by swifts. They may not perceive humans as predators, or at least us as a threat to them, given their acceptance of their human-dominated landscape and life-style.
    The Kittatinny Ridge, a “leading line” and superhighway for diurnal raptors migrating south and north, is the source for raptorial birds visiting feeders and hunting squirrels in the Allentown urban/suburban area (Stevenson, Urban occurrence of raptors along a leading line, work in progress). One can see the PPL Tower from the Bake Oven Knob, Hawk Mountain, and Little Gap hawk watches with an unaided eye. Cooper’s Hawks have about ten times the sight of humans in binocular vision (their eyes being more set forward than Sharp-shinned Hawks (Accipiter striatus)). No doubt the avian activity can be detected by accipitrine hawks in Allentown, especially on top of PPL Tower, the tallest building in Allentown. Anecdotal evidence exists for goshawk breeding behavior in the continuous forest of the Kittatinny, but thorough investigation remains, but there is definite evidence of fall, at least migrating individuals through December 15, and perhaps spring migrants.
    A literature search indicated flocking and freezing in twelve other species including Tufted Titmouse (Baeolophus bicolor) and perhaps some wading birds (Waite and Grubb 1987; see Kushlan 1981).
    Bull and Blumton (1997) reports that Vaux’s Swift (Chaetura vauxi) roosting in trees. The Common Swift (Apus apus) has been recorded roosting in trees, hanging down from branches with the wings spread out (Gyngell 1897; Holmgren 1993). Apodinae is pamprodactylous, whereas Chaeturinae are anisodactylous (Collins 1983). It was not clear to me whether these birds could have been torpid or not, but no mention of the word is in the articles. But they could have been. As to the Chimney Swifts, they were quite alert.
    One can assume until reported otherwise, because of swift foot morphology, that there was a trough or ridge at the end of the ledge, perhaps to direct rain that enabled the swifts to “stand”. I was unsuccessful in trying to gain access to the top of the tower, or have an employee describe it to me. White-throated Swifts’ feet have two toes working forward and two back, though in death, they all point forward (Ehrlich et al 1988).
    The configuration and horizontal is a unique observation. The birds were probably resting on their tarsi with their toes pointed forward. This is in the same position they are in when perched on a vertical surface. Under unusual circumstances, such as the presence of avian predators, it is plausible that they may wind up horizontal (C. Collins pers. com.).
    The observation by the farmer may have been a one-time occurrence since horizontal perching is not readily seen by observers (C. Collins pers. com.).
    In conclusion, understanding avian morphology and behavior is paramount to placing species correctly in evolutionary history as an auxiliary to molecular analysis, especially in delineating new relatively monomorphic subspecies. Also correct morphology matters in bird rehabilitation. A simple correction like that of foot anatomy, over time after many observations, could change information regarding habitat use. More research, using captive individuals injured beyond repair, as well as observations in the wild, are necessary. Despite some effort, I was not able to see this phenomenon occur again. I apologize for the expansion of time from the time of my observation until when I reported it. Also, and this is a little farfetched, there is a possible question in my mind whether swifts and others like swallows and martins often feed in flocks to use each other as aerial “beaters”, or for information, in a modified form of cooperative feeding or hunting (see Cottam et al 1942; Palmer 1962; Bednarz 1988; Bednarz and Hayden 1987).


    ACKNOWLEDGEMENTS

    I thank Chimney Swift BNA author C. Collins most of all, without whose kind previews this paper would not be a reality. Thanks go to R. Root for statistical help. I thank R. Ricklefs for comments on an earlier draft of the manuscript. I thank an anonymous wildlife officer at the Royal Society for the Protection of Birds for the “haunches” term and an overseas confirmation of this behavior.

    LITERATURE CITED


    Bednarz, J.C., and T.J. Hayden. 1987. (Cooperative hunting in Harris’s Hawks.) Proc. Annual Meeting Raptor Research Found. , Oct. 28-31, Boise (abstract).

    Bednarz, J.C. 1988. (Cooperative hunting in Harris’s Hawks.) Nature 239: 1525-1527.

    Bull, E.L., and A.L. Blumton. 1997. Roosting behavior of postfledgling Vaux’s Swifts in northeastern Oregon. J. Field Ornithol. 68 (2): 302-305.

    Cink, C.L., and C.T. Collins. 2002. Chimney Swift (Chaetura pelagica). In The Birds of North America, No. 646 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

    Collins, C.T. 1983. A reinterpretation of pamprodactyly in swifts: a convergent grasping mechanism in vertebrates. The Auk 100 (3): 735-737.

    Cottam, C., et al. 1942. Cooperative feeding of White Pelicans. Auk 59 (3): 444-445.

    Dexter, R.W. 1991. Sociality of Chimney Swifts (Chaetura pelagica) nesting in a colony. North American Bird Bander 17 (2): 61-64.

    Ehrlich, P.R. 1988. The birder’s handbook. Simon & Schuster Inc., N.Y., N.Y.

    Gyngell, W. 1897. Common Swift roosting in a tree. Zoologist (Series 4) 1: 468-469.

    Holmgren, J. 1993. Young Common Swifts roosting in foliage of trees. British Birds 86: 358-369.

    Kushlan, J. A. 1981. Resource use strategies of wading birds. Wilson Bull. 93 (2): 145-163.

    Lack, D. 1956. Swifts in a tower. Methuen & Co LTD, London, UK.

    Palmer, R.S., ed. 1962. Handbook of North American birds. Vol. 1. Loons to flamingos. Yale University Press, New Haven, CT.

    Ryan, T.P., and C.T. Collins. 2000. White-throated Swift (Aeronautes saxatalis). In The Birds of North America, No. 526 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, Pa.

    Waite, T.A., and T.C. Grubb, Jr. 1987. Dominance, Foraging and Predation Risk in the Tufted Titmouse. Condor 89 (4): 936-940.


    1 946 Seneca Street, Apt. 11, Fountain Hill, PA 18015

    2 grantstevenson44@yahoo.com
    Monday, June 27th, 2011
    12:48 am
    Hypothetical Beginning of Book on Amateur Ornithology
    How many of us ever got to know a wild animal? I do not mean merely to meet with one once or twice…but to really know it for a long time…and to get an insight into life and history.

    - Earnest Thompson Seton in THE AMERICAN CROW AND THE COMMON RAVEN by Lawrence Kilham

    AMATEUR ORNITHOLOGY


    Stevenson -2- Avian Behavioral Ecology


    1. COMMON BIRD BEHAVIOR: Introduction

    The study of animal behavior, or ethology, is called by the British “behavioral ecology”, a term I prefer personally because I believe it describes it best and is all-encompassing on
    the subject. For instance, behavioral ecology also studies human behavior, though not often. It also is not afraid of biological theory (hence the journal, The Journal of Biological Theory). I have had the privilege of belonging to Oxford’s The International Society for Behavioral Ecology (ISBE), which publishes the good journal BEHAVIORAL ECOLOGY. Behavioral Ecology is not interested in “how”, morphological and physiological questions, but “why”, evolutionary adaptive questions. What is the selective reason for this behavior? How does it help the bird “cope” (adapt) to its environment? As you can see, behavioral ecology has helped the sciences of psychology and neuropsychiatry endlessly. The comparative method is widespread in organismal behavioral science. It allows scientists and amateurs to compare different species from different families, orders, and even classes (mammals, birds: higher vertebrates) if the evolutionary reason for the two similar behaviors is the same. Originally used by morphologists, Konrad Lorenz of Germany, one of two fathers of animal behavior, with Niko Tinbergen of Norway in mid-last century, applied it to the behavior of waterfowl and gulls, respectively. Another method is contentious among professional ornithologists: whether to "tame" your subject species, say with whole kernel corn with American Crows (Corvus brachyrhynchos), so they will act close and natural around you, or whether such taming causes them to act in unnatural ways. Many raptor biologists cite studying manned raptors in falconry, with its training, for hunting data, as artificial. I personally do not know the answer to the taming issue. It may depend on what species, what journal, how you write it and account for possible anthropomorphic effects, if you can account for them all, and whether the species has the intelligence to be tamed in the first place (more on cognitivity in birds later- see crow section).

    Stevenson -3- Avian Behavioral Ecology

    For further reading on behavioral ecology, start with BEHAVIOURAL ECOLOGY: AN EVOLUTIONARY APPROACH by John R. Krebs and Nicholas B. Davies. Then read ANIMAL BEHAVIOR: AN EVOLOUTIONARY APPROACH by
    John Alcock. These are the best overviews. The Alcock book is more readable and palatable to the birder, but Krebs and Davies wrote BEHAVIOURAL ECOLOGY: AN INTRODUCTION for that purpose, too. For an understanding of animal signals, such as bird vocalizations, see THE BEHAVIOR OF COMMUNICATING: EA ETHOLOGICAL APPROACH by W. John Smith, the doctoral advisor at The University of Pennsylvania of Dr. Robert Ricklefs, the foremost avian ecologist in the United States. If you want an understanding of bird ecology, I suggest AVIAN ECOLOGY by Christopher Perrins and T.R. Birkhead. Dr. Perrins is the current Director of the Edward Grey Institute of Field Ornithology at Oxford. This book is quite understandable, and affordable, at www.buteobooks.com. For you closet ornithologists, try THE ECONOMY OF NATURE by Dr. Ricklefs. AVIAN ECOLOGY is more oriented toward field avian ecology, but this book delves into depth more what every serious student should know. (Bob Ricklefs and Sir John Krebs are very interested in helping the amateur. I will ask them if they can help you via email once I get five names- via email- no more, and if they are not too busy, they can converse with you and preview your papers prior to submittal.) Do not, I repeat, do not buy these books unless you are particularly flush and can afford it. If you can afford used textbooks, try www.harvestbooks.com. Otherwise, I always get them through Inter-library Loan from my public library and take notes and take down the
    Stevenson -4- Avian Behavioral Ecology

    citation. Simple as that: all I have to pay for is the minimal ILL fee. The general rule of thumb regarding textbooks is of two schools: one, newest editions have the most up to
    date information, such as in biology, and two: subsequent editions don’t offer much m
    information but, with the permissions of the authors, publishing companies make more business in a hard business by putting out more-and-more editions, like in statistics texts. It is subject-dependent, and up to the reader/user. Also, I suggest ON AGGRESSION, KING SOLOMON’S RING, and [book on ethology and the Greylag Goose] by Konrad Lorenz and THE CURIOUS NATURALIST and THE HERRING GULL’S WORLD by Niko Tinbergen. There are other important books by these two, and papers, in the textbooks’ bibliographies. But some of their material is out-dated. For an example, call The University of Oxford Press in the U.S. and request free sample of BEHAVIORAL ECOLOGY journal at 1-800-852-7323 (jnlorders@oup-usa.org). If you have the funds, a student membership to the ISBE is $38; a regular one is $65. I highly recommend Donald Stokes’s A GUIDE TO BIRD BEHAVIOR, VOLUME 1, of all common species; though some subsequent scientific published papers have altered some of the book’s information, much of it still holds true. Stokes was the first to write an entire book of avian behavior for popular consumption, and ILL can find it in public libraries and. As you know, the scientific process means it is constantly being rewritten: Stokes was the first compendium that updated the classics since Catesby, Bartram, Audubon, Wilson, and the 19th and 20th century classics like Ridgeway, Coues, Bendire, Baird, Cooper, Chapman, Grinnell,

    Stevenson -5- Avian Behavioral Ecology


    Griscom, Bent, Sutton, Heinrich, Davies, Krebs, etc., in readable, palatable form for the public.
    For a partial, scientific, short course-outline of ethological concepts and theory, see Appendix I. It may behoove you to take an undergraduate course in ornithology. Stephen Kress's out-of-print book THE AUDUBON SOCIETY HANDBOOK FOR BIRDERS has such a list of colleges and courses in the back (see libraries or Harvest Books website). Muhlenberg College has an ornithology course for biology majors during the day and a non-major BIOLOGY OF BIRDS course in the evening adult Wescoe School. Adults can take for credit or audit either. Cornell University offers a BIRD BIOLOGY course through the computer through its Cornell Lab of Ornithology. In order to take it, you must pay for it or get a full scholarship through the Lab. Or you can buy their book HANDBOOK OF BIRD BIOLOGY for $99.50 (65 pounds) from Princeton University Press (www.pup.princeton.edu).

    AMERICAN ROBINS

    Definitions

    Optimal foraging is a behavioral ecological term defined by Robert E. Ricklefs (1993, The economics of nature, W.H. Freeman, New York.) as “a set of rules, including breadth of diet, by which organisms maximize food intake per unit time or minimize the time needed to meet their food requirements; risk of predation may also enter the equation for optimal foraging”. Optimal giving up time (GUT) is “the time that an organism should remain within a patch of resources before moving onto the next in order to maximize its rate of food intake”. Optimization of foraging is discussed in detail by Krebs (1984, Behavioural ecology: an evolutionary approach, Sinauer Associates, Inc., Sunderland, MA, for newer editions, and Blackwell Scientific Publications, Oxford, for earlier editions) and Ricklefs (1993).

    Stevenson -6- Avian Behavioral Ecology


    Anti-predator behavior is avoidance behavior toward predators of all classes of animals based on species size: small species tend to forage, roost, and breed near or in foliage, middle-sized birds like American Crows (Corvus brachyrhynchos) tend to go to woody
    foliage and also outmaneuver avian predators in flight, and larger birds like Common Ravens (Corvus corax) and gulls outmaneuver and the ravens will turn on aerial predators. There are exceptions to this observation for a lot of species. Perhaps the most exemplary is the White-throated Swift (Aeronautes saxatalis), which even escape the Peregrine Falcon (Falco peregrinus) out west (Lima, Steven L. 1993, Ecological and evolutionary perspectives on escape from predatory attack: a survey of North American birds, Wilson Bull. 105(1): 1-47.).

    Part 1. Foraging Patterns

    I observed American Robins (Turdus migratorius), n100, foraging for earthworms (Oligochaeta: Lumbricdae) on the suburban lawns of Cedar Beach Park in Allentown, Lehigh County, eastern-central Pennsylvania (40.5968N x –75.5124W), in 1992, in a small flock with Common Grackles (Quiscalus quiscula). Birds tended not to forage straighter and in shorter bouts after a successful encounter with prey (Mood’s Median Test, N=1, 2= 0.1, p= 0.05, df= 1). Birds also tended to turn less acute angles after a successful
    Stevenson -7- Avian Behavioral Ecology

    probe (median= 140; N=1, 2= 628.4, df= 1, p= 0.05). The mean angle degrees after a successful run was 134 (SE13, cv= 40%). The mean angle degrees after not catching a worm was also 134 (SE13, cv= 38%). The mean angle after a successful run was 141.7 (n= 16, SE11.7, cv= 33%). The mean angle between unsuccessful runs was 140.6 (n= 16, SE12.3, cv= 36%). Not all robins do this behavior (Sign Test, z= 10, p>
    0.09, N.S. (non-significant)), but the observation was not unique (z= 0, p= 0.01). However, Sign Tests are low-powered statistically.
    My next robin optimal foraging project at the following site (in Part 2) will involve this spring observing GUT with a stopwatch with microseconds, measuring time of foraging on micropatches of lawn before they give up and move between patches in four categories, individuals, pair-bonding pairs, small flocks ( 25 individuals), and large flocks ( 25 individuals), either due to predator presence or searching for more food. Summer breeding foraging dynamics may be different either in the incubation, nestling
    or fledgling stage. Also, worm catch (after detection) and beak handling times in microseconds will be recorded. At least thirty samples each of these two variables will be recorded: a Spearman’s R will be done if the two samples are even in number, a Mann-Whitney U if uneven. Seed handling time in finches (Darwin’s Finches; Abbot, I., et al, 1975, Seed selection and handling ability of four species of Darwin’s Finches, Condor 77: 332-335; Grant, P.R., 1986, Ecology and evolution of Darwin’s Finches, Princeton University Press, Princeton, New Jersey.) and North American selected Fringillidae and Emberizidae finches (Willson, M.F., 1971, Seed selection in some North American
    Stevenson -8- Avian Behavioral Ecology

    finches, Condor 73: 415-429.). Dr. Willson examined fruit choices by robins (1994, Fruit choices by captive American Robins, Condor 96(2): 494-502.), but an average worm handling time has not been calculated, to the best of my knowledge. The average earthworm weighs about [0.2g] and is not “chewed” buy the upper and lower mandibles,
    but the head is tilted back and the item swallowed whole, thus a thin beak (shallow depth). A rule to all evolutionary biology is: “form fits function”.

    Part 2. Avoiding Predation

    Anti-predator behavior is staying next to foliage while ground foraging, say J.O. Oyugi and J.S. Brown (2003, Giving up densities and habitat preferences of European Starlings and American Robins, Condor 105(1): 130-135.). But Lima (1993) points out they
    often seen, including by me, singularly to large flocks in the middle of lawns. Why? Evolution should have an answer. I observed foraging spring and fall flocks since 1994 at the grounds of the Allentown State Hospital (ASH), Allentown, Lehigh County, Pennsylvania (40.6151N x –75.4293W), where, because I am on the Board of Trustees, the administration and security has so graciously allowed me to use it as a study site (Acknowledgements: Gregory Smith, President and CEO, and Ms. Tiffany Hudock, Administrative Assistant to Mr. Smith). The robin alarm note is a species-specific signal that is barely audible to the human ear (See: Caldwell, G.S. 1986, Predation as a selective force on foraging herons: effects of plumage color and flocking, The Auk 103: 494-505.).
    Stevenson -9- Avian Behavioral Ecology

    So I will purchase a Radio Shack or Sears sensitive pocket cassette recorder, or go on Ebay and see if they have plastic parabolic reflectors attached to amplified microphones attached to sensitive playback pocket recorders capable of making and playing continuous loop tapes or CDs. I saw flocks get up and shift places, a kind of “following-the-leader” to new found food patch or in response to human movement, but when they flew completely away, they seemed to be often with American Crows or European Starlings (Sturnus vulgaris), and
    possibly Common Grackles and Red-winged Blackbirds (Agelaius phoeniceus), and even more remotely so, Brewer’s (Euphagus cyanocephalus) and Rusty (Euphagus carolinus) Blackbirds. (There was the chance for a rare Emberizine or House Sparrow (Plocidae: Passer domesticus), but I only remember a Grasshopper Sparrow (Ammadramus savannarum)-call in a field full of Red-wings, that was a filled-in wetland, in another part of the property. Please see that ASH is in the suburban buffer zone between Allentown and Bethlehem. I may start a spring hawkwatch there because it overlooks the Lehigh River and I’ve observed quite a bit of raptor migration activity from there (fortunately
    the governor and state senate appointed me to the board there twice, making it Grant’s little private bird preserve with Mr. Smith’s kind permission.) Were they responding to cues, visual or auditory, from the other species? Or could the warn themselves? If so, was it with visual or auditory signals, or both? How did they react towards an avian or mammalian predator? Did they ignore them for a time? How long? (Predator Presence

    Stevenson -10- Avian Behavioral Ecology

    Tolerance (PPT)- my term- defined by time of ignorance, per separate taxa of predator, including hominid).

    AMERICAN CROW

    Part 1. Optimal Cooperative Feeding

    I define optimal cooperative feeding in American Crows as the mutual use of sentinels as predator guards while others feed below, then after awhile they switch off, and the sentinels feed. It is optimal because all individuals get to feed while not worrying about “looking up” for predators, optimizing energy intake. European Starlings do it (), and an observer of Canada Geese (Branta canadensis) told me he feels a drake always watches for predators in a flock at Cedar Beach: as he gets closer, it honks loudly and repeatedly and the flock moves away from the intruder.
    I have observed many instances of sentineling, but because I was going somewhere, I could not stick around for the switch-off. Sentineling in corvids is, though not well, documented. Lawrence Kilham observed this in only small groups (1989, The American Crow and Common Raven, Texas A&M University Press, College Station, TX.), but I have seen this behavior in mass winter roosts up to 50,000 birds (winter roosts have been observed up to 200,000 birds documented, they may go larger according to the carrying capacity of the habitat), the more birds on the ground, the more sentinels in trees. Winter roosts travel up to 81 kilometers a day in search of food (Terres, J.K., 1980, The Audubon encyclopedia of North American birds, Alfred A. Knopf, New York.). This is because Optimal Foraging Theory says once at a foraging habitat patch, it is the Law of Diminishing Returns. Eventually, it is worth the energy expenditure to travel elsewhere.

    I have seen cooperative feeding in crows personally only once according to my mutualism definition because of my itinerant schedule. It occurred at a street in front of
    2/21/06 -10- Common Bird Behavior

    Cedar Crest College, on the southern border of Cedar Beach Park in Allentown. It involved only two crows, possibly cooperatively breeding yearlings from a nearby nest attended to by the parental pair. Both took turns sentineling and and feeding in the road for ten minutes per bout, sentineling from approximately the same distance and height, feeding on what I hypothesize to be road-cracked acorns. American Crows () and Japanese Jungle Crows (Corvus macrorhynchos japonensis) in Tokyo () have been shown to use automobiles as nutcrackers, as tools, including American Crows with walnuts (Juglans spps.; Black Walnut Juglans nigra). A Sign Test calculated that the probability of all American Crows cooperatively feed, by my definition and sample, is 99%, very significant (z= 1.41, p= 0.01).
    Common Ravens (Corvus corax) optimally cooperatively feed and roost by both sharing information and recruiting (Dall, S.R.X. 2002, Can information sharing explain recruitment to food from communal roosts? Behavioral Ecology 13(1): 42-51.). Other species, like the Red-throated Caracara (Daptrius americanus), cooperatively feed (Thiollay, J.-M. 1991, Foraging, home range use and social behavior of a group-living rainforest raptor, the Red-throated Caracara (Daptrius americanus), Ibis 133: 382-393.). American White Pelicans are another, more famous example to American ornithologists and birders (Cottam, C., et al 1942, Cooperative feeding of white pelicans, Auk 59(3): 444-445; Palmer, R.S. 1962, Handbook of North American birds. Vol. 1. loons through flamingos. Yale University Press, New Haven, CN.).
    Corvidae (Crow Family) is one of the most cognitive of avian families. It has a relatively large brain to body mass ratios of all avian taxa. Cooperative breeding, like in American Crows, is a characteristic of cognitivity (Ricklefs, R.E. 2004, The cognitive face of avian life histories: the 2003 Margaret Morse Nice Lecture, Wilson Bull. 116(2): 119-133; Kilham, L. 1984. Cooperative breeding of American Crows, J. Field Ornithol. 55: 349-356; see also Ricklefs, R.E. 1975, The evolution of co-operative breeding in birds, Ibis 117: 531-534.).
    (Brain and eye size coevolved with prey capture and nocturality in birds, according to L.Z. Garamszegi et al (2002, Coevolving avian eye size and brain size in relation to prey capture and noctornality, Proc. R. Soc. Lond. B 269: 961-967.))
    Birds are instinctive, live in the present moment (except for memory and insight), and are cognitive. Humans developed cultur
    e, advanced mathematics and science, and thus intelligent.
    Sunday, June 26th, 2011
    5:50 pm
    Elevational Bird Distribution Example
    ELEVATIONAL DISTRIBUTION OF SOME PENNSYLVANIAN BREEDING BIRDS

    Grant Stevenson
    5/30/07


    Kittatinny Ridge, North of Bath, Northampton County


    Base to Mid-story

    1.Yellow Warbler
    2.Red-bellied Woodpecker
    3.Red-eyed Vireo
    4.Yellow-throated Vireo
    5.Mourning Dove
    6.Blue Jay
    7.Black-and-White Warbler
    8.American Robin
    9.Worm-eating Warbler
    10.Ovenbird
    11.Scarlet Tanager
    12.Song Sparrow- edge
    13.Eastern Wood-Pewee
    14.Northern Flicker

    Mid-way

    15.Blue-headed Vireo
    16.Black-capped Chickadee
    17.Tufted Titmouse
    18.Blue Jay
    19.Wood Thrush
    20.Blackpoll Warbler
    21.Worm-eating Warbler
    22.Ovenbird
    23.Scarlet Tanager

    Top Portion

    24.Downy Woodpecker
    25.Eastern Towhee
    26.Rose-breasted Grosbeak


    There was no noticeable succession of plants, singing perches, food availability, cover, water, etc.: all was deep forest secondary successional deciduous woods with two springs. The gradient was seamless. This is inferred, not empirical, so may be different on other slopes.


    HELPFUL EXPLANATORY INFORMATION

    Wiens, J.A. 1989. The ecology of bird communities. I. Foundations and patterns. Cambridge University Press, Cambridge. Pp. 169, 269, etc. (figs.)

    - Grant Stevenson, 946 Seneca Street, Apt. 11, Bethlehem, PA 18015, grantstevenson44@yahoo.com.
    5:28 pm
    My Current Contact Information
    Grant Stevenson
    946 Seneca Street, Apt. 11
    Fountain Hill, PA 18015-2607
    phn 610-867-2862
    cell 484-353-9399
    eml grantstevenson44@yahoo.com
    5:19 pm
    Birding Trip Report
    A BIRDING TRIP TO LEHIGH MOUNTAIN, ~2006



    By Grant Stevenson



    Lehigh Mountain in Fountain Hill is part of South Mountain, the Highlands. A friend and I birded it at 7-8am on July 8 as part of the 2nd Pennsylvania Breeding Bird Atlas and the Pennsylvania Society for Ornithology's Special Areas Project. The whole preserve is about 2000 acres. We went up and down Constitution Drive from Walking Purchase Park. The site is described in the Lehigh Valley Audubon Society's bird guide Birds of the Lehigh Valley and Vicinity, available on their website (go to Eastern PA Birding: www.users.fast.net/becard/: they have the link).
    It was clear, mild to hot and humid, with no wind. Lehigh Mountain is about 800 feet high with mixed deciduous woods.
    We saw 26 species, 243 individuals, at 4.7 individuals per species per hour. Here is a species list of the species that may be on the Audubon Watchlist (www.audubon.org)* and/or the PA Species of Conservation Concern list (www.pgc.state.pa.us):

    Eastern Phoebe
    Eastern Pewee
    Wood Thrush*, 100+, indicating a bumper crop of fledglings
    Veery, a type of forest thrush
    Red-eyed Vireo
    Warbling Vireo
    Worm-eating Warbler 3*, heard only
    American Redstarts feeding fledgling
    American Redstart sounding almost like the coveted Cerulean Warbler*
    Scarlet Tanagers feeding fledglings
    Eastern Towhee

    What is interesting to me, having birded for a decade Lehigh Mountain, the Dutch Hills in Allentown, and Sand Island, that according to elevation, fragment size, vegetation, and proximity to water, etc., some species are consistently "geophilic" and refuse to "gap-cross" year-to-year between fragments of the Highlands here in the Lehigh Valley. Home-range gap-crossing is under intense study by ornithologists interested in metapopulation dynamics because of the ever-increasing human-caused fragmentation of remaining habitats. What species are most likely to survive? It seems large species are more willing to gap-cross and cross wider gaps. These concepts, and research, will become important when planning for the Highlands' biotic future.
    The Highlands in Pennsylvania continue to be a major source of breeding Wood Thrush thus far little studied in the ornithological literature, another reason why we must not let this gem in our backyard become too fragmented.
    4:56 pm
    The Hunting of Raptors, Partial Paper
    HUNTING STRATEGIES AND METHOD OF ATTACK OF SELECT RAPTORS

    Grant Stevenson 1, 2

    1 946 Seneca Street, Apt. 11, Bethlehem, PA 18015

    2 pahawkowl@yahoo.com

    __________________________________________________________________________________________________

    Abstract.- Optimal hunting is the optimization of calories and nutrition hunted daily while minimizing energy expenditure and other costs, like predation of smaller raptors. Optimal foraging theory is a simple behavioral ecological model for foraging behavior that over about two decades have become a mathematical and computer construct and tool for explaining and predicting this phenomenon in birds, including raptors. In this paper, I review a portion of the published ornithological literature of select North American raptors. Also discussed is game theory, like hawk and dove. The purpose of Evolutionary Stable Strategies (ESS), behavioral phenotypes developed over evolutionary time is to achieve maximum adaptivity. This involves optimal food acquisition to metabolic output. While game theory is now considered more current than optimization, since the two strategies have been trading places with each other since the 1960's, I treat both equally.

    KEY WORDS: perch hunting, stop-and-go hunting, marginal value theorem, resource depression, ESS, game theory, hawk, dove.



    AMERICAN KESTREL (Falco sparverius)




    Prey Type
    Method:
    Perch
    Hover
    Insect

    578
    250
    Vertebrate

    37
    9
    From Rudolph (1982)

    Rudolph (1982) found that kestrels used perch hunting occupied a greater amount of hunting attempts. Collopy and Koplin (1983) found perching, flight, and hover-hunting prominent in that order for wintering females. Varland et al (1991) found "social hunting" significant in perch and ground hunting. Scrubb (1981) found perch and hover-hunting significant in the Common Kestrel (Falco tinnunculus). Ultimate and proximate factors intertwine to indicate how well and what method animals use to obtain food.
    Kestrels have a mean strike velocity with the feet of 585 cm/sec. Before impact wings are spread in typical accipiter-buteo brake position (Goslow 1971).
    Rudolph (1982) wrote an excellent paper outlining the energetics, or management of energy and time, between the three hunting tactics and some of the birds other habits associated with hunting. In it he discusses giving-times, central place foraging, optimal foraging, patch use, and other optimization terms. One example of another optimal hunting term is resource depression, where a prey voluminous patch is slowly harvested to the point of opposite negative value, also called the Marginal Value Theorem. (In this, prey quantity is limited, and a population regulating force no matter its initial size. If a hawker slowly (and inhumanely) decreases the prey "load" in a "loading curve", indeed his/her bird may keep more quarries for itself. Organisms in the wild forage in discrete habitat patches or archipelagos, and migrate back and forth, called immigration, and colonization. This is a "metapopulation" concept. My pet theory is that the declining (RRF) eastern population of kestrels has possibly been forced into such a metapopulation, with its dynamics, due to habitat destruction. Higher vertebrates may use "insight learning" to remember lucrative patches, thus depleting old patched and becoming vulnerable to sprawl.) Kestrels may manage their energy expenditures much in the same way as hummingbirds, sunbirds, and Pied Wagtails, according to resource amounts. Central place foraging, when applied to kestrels (Rudolph 1982), denotes the use of the nest as a base of operations, while giving-up times indicates times that it takes the kestrel to lose interest in his/her patch and move on.
    Organisms managing time and energy, so pivotal in survival, is a crucial constraint in time activity budgets (Krebs and McCleery 1984).
    The size of preferred prey may be correlated to species' size, the range of a species' prey base that is. Called K and r-selection (MacArthur and Wilson 1966; Pianka 1970), small species like falconets (Microhierax spps.), pygmy falcons (Polihierax spps.), the Laughing Falcon (Herptotheres spps.), forest falcons (Micrastur spps.), some caracaras (Milvago spps.), etc., have many eggs and their mean adult annual survival (1.5 years for American Kestrels) is low. K-selected birds are low in productivity, live longer, and have "delayed reproduction", such as eagles, harriers, large falcons, and large accipiters.


    EUROPEAN GOSHAWK (Accipiter gentilis gentilis) 3
    3 See Raptors of the World, Ferguson-Lees and Christie, 2005, for pictures and biological details.
    _______________________________________________________________________________


    Perhaps the best example of game theory applied to raptor hunting, this hawk was observed by Kenward (1978) performing the "hawk and dove" game (Smith 1982) literally, with Wood Pigeons (Columba palumbus). Attacks on single birds, and small flocks, were more successful than on large flocks, with which would fly away at once and confuse and overwhelm the goshawk. Falconers should be advised that this is the case with most species and to keep quarry down in number. There was selection for defective and diseased birds, but not age and sex.
    In the BNA life history, no foraging information section is indicated.


    PEREGRINE FALCON (Falco peregrinus)...





    INCOMPLETE PROJECT
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