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ILLUSTRATING HUMAN WILDLIFE CONFLICT BY EVAN NEAL A Thesis Submitted to the Division of General Studies New College of Florida in partial fulfillment of the requirements for the degree Bachelor of Arts Under the sponsorship of Dr. Sandra Gilchrist & Dr. Meg Lowman Sarasota, Florida March, 2010
ii Table of Contents page Acknowledgements..iii List of Figures..iv Abstract.v Introduction ...1 Chapter 1...6 The Efficacy of and Human Affinity for Illustration....6 Anatomical Realism and Postmortem Subjects in Scientific Illustration....11 The Depiction of Raptors in Popular Cult ure..14 Chapter 2..19 Human Raptor Conflict...19 Keys for Raptor Conservation: Evolution and Adaptations20 The Diurnal Raptor..20 Strigiformes..25 Keys for Ra ptor Conservation: The Raptor as an Apex Predator26 Human Raptor Conflict: Direct Persecution31 Human Raptor Conflict: "Incidental Take".33 Roadways.34 Electrocution35 Wind Turbines .37 Poisoning and Biomagnification..38 Other Sources...41 Stewardship..42 Chapter 3...43 Illustrations...43 Turkey Vulture, Cathartes aur a ...44 Cooper's Hawk, Accipiter cooperii ..46 Red Tailed Hawk, Buteo jamaicensis ..48 Bald Eagle, Haliaeetus luecocephalus .........................50 Works Cited..51 Glossary 58
iii Acknowledgments & Dedication A hearty thanks to all my friends at the Chattahoochee Nature Center; Brian, Kathryn, Dawn, Susan, Amy, Agnes, Henning, Jim & Norma. To North Springs High School for hosting the mentorship program that int roduced me to wildlife rehabilitation. To my academic advisor and sponsor, Dr. Gilchrist for being someone who believes in good education and for sticking with me and sticking it to me whenever necessary. To Dr. Lowman, for being a great inspiration and s miling so very often. To New College in general, it's been really cool. To the fam: Mom, Dad, Morgs, Grampa, Aunt Cindy, Uncle George, the dogs, and my newfound cousin Peter Hooten. To Kathryn Dudeck, Lee Fox, Diana Flynt, Kevin Barton, and Gail Straight for helping me by contributing great data, information, and experience on wildlife rehabilitation. To all other wildlife rehabilitators, doing noble work. Thanks to my roommates, all my friends, the Great Universal Earth Spirit, and of course to those fa bulous birds of prey, especially the Red Tailed Hawk that flew down over me and a dozen ten year olds at Camp Kingfisher last summer to catch a chipmunk in a bush, returned to its perch and then disemboweled its meal in full view of the campers, discarding the entrails into a magnificent pile of great excitement and curiosity onto the green grass below.
iv List of Figures page Figure 1: Interior of the Chattahoochee Nature Center Wildlife Clinic...3 Figure 2: 33,000 year old etc hing of an owl from the Chauvet Cave..........6 Figure 3: Robert Hooke's illustration of a flea....8 Figure 4: Illustration from Frederick II's De Arte Venandi cum Avibus .7 Figure 5: Anatomical illustration from Vesalius's De Human i Corporis Fabrica .12 Figure 6: Illustration from Hunter's The Anatomy of the Gravid Uterus in Figures .........................................................................................13 Figure 7: First Great Seal of the United States...15 Figure 8: Haida formline depiction of an eagle...16 Figure 9: Superciliary ridge of a Red Shouldered Hawk, Buteo lineatus ........21 Figure 10: Comparative illustration of avian beaks.22 Figure 11: Cl osed foot of a Red Tailed Hawk, Buteo jamaicensis ..23 Figure 12: The formidable talons of the Great Horned Owl, Bubo virginianus ..24 Figure 13: The distinct facial disk of a Barred Owl, Strix varia ..25 Figure 14: Illustration depicting dif ferences in an ecosystem where a top predator is both present and absent ....31 Figure 15: Hawks shot at Kittatinny Ridge, Pennsylvania...32 Figure 16: Electrocuted Red Shouldered Hawk, Buteo lineatus ..35
v I LLUST RATING HUMAN WILDLIFE CONFLICT Evan Neal New College of Florida, 2010 ABSTRACT Anthropogenic causes account for a major source of injury and death to birds of prey in the United States. Ranging from collisions with automobiles to poisoning to gun shot, conflicts between humans and birds of prey reflect an array of human activities detrimental to the success of these important apex predators. In order to raise awareness and concern for this issue, this thesis explores a biological and ecological im petus for raptor conservation, employing the complimentary means of illustration to enforce information and incite learner involvement. Dr. Sandra Gilchrist, PhD Division of Natural Sciences Dr. Meg Lowman, P hD Division of Natural Sciences
1 INTRODUCTION The word "raptor" is another name for a bird of prey. Defined by their curved beaks for tearing flesh, strong feet and sharp talons for subduing prey, and keen eyesight, raptors in the United States occupy an important niche atop the food ch ain; they are apex predators built for the kill. Three orders, Falconiformes, Strigiformes, and Ciconiiformes, encompassing 53 species of eagles, hawks, owls, osprey, kites, vultures, and falcons comprise the raptors of North America. The history of human raptor conflict in the United States would be incomplete without mention of the placement of our nation's national bird, the Bald Eagle ( Haliaeetus leucocephalus ), on the Endangered Species List exactly 200 years after the Declaration of Independence was signed, or of the indiscriminate shooting of migrating hawks along Kittatinny Ridge, Pennsylvania, or of the California Condor's brush with extinction and captive resuscitation. A brief chat with a local raptor rehabilitator or wildlife veterinarian may be even more revealing. In America a paradox exists between humans and birds of prey; raptors are nationally elevated as icons, symbolizing American values of freedom, strength, and independence, yet raptor lives are perpetually threatened by the American w ay of life. Anthropogenic sources of injury and death such as collisions with automobiles, electrocution atop utility poles, gunshot wounds and direct persecution, environmental contamination, and poisoning are responsible for many of the thousands of woun ded and deceased raptors reported annually to the United States Fish and Wildlife Service. All raptors in North American are currently protected by law, but conflict persists. The Audubon Center for Birds of Prey in Maitland, Florida,
2 for example, admitt ed a total of 540 patients in 2009 alone. In 2008, 673 raptors were taken in, a number closer to their annual average of 650 patients per year (personal communication Diana Flynt). The Chattahoochee Nature Center Wildlife Clinic in Roswell, Georgia recei ved 187 raptors in 2009 (pers. comm. Kathryn Dudeck; Figure 1). It is estimated that between 85 and 95 percent of raptors received by wildlife rehabilitation clinics across the country suffer anthropogenic sources of injury (pers. comm. Kevin Barton). Th ese facilities are able only to assess injured or deceased raptors as they are willingly reported, with accounts given only by those who aware of them. Any sort of figure representing the total number of raptors suffering from anthropogenic sources of inj ury annually is, and will likely continue to remain unknown. Inside any wildlife rehabilitation facility treating raptors, one encounters stories of raptor injury, persecution, and death instigated by human involvement, both direct and indirect. The most poignant cases are always those involving people, wherein these incredible creatures have been disallowed their ability to survive in the wild. The case of an owl chick ousted from its nest may be regarded as unfortunate; but a case involving an eagle una ble to fly, hunt, or reproduce because it was electrocuted atop a power line might be regarded with frustration, anger, a sense of empathy, even a feeling of shared responsibility or desire to help. Because I have been personally and emotionally involved with so many examples of human raptor conflict through work in various wildlife rehabilitation facilities, I have chosen to write and illustrate my thesis on human raptor conflict as it
3 occurs in the United States. In an attempt to educate others, I have selected illustration as an essential and complimentary instructional venue to the text. Representational and scientific illustrations are a useful tool by which we record our observations of nature. My most plaintive and lasting observations were those of raptors adversely affected by human activities. The telling bodies of those birds whose lives were cut short are the ones I chose to illustrate. While the drawings included in this thesis are representative illustrations depicting phenomena observed in natural subjects, such individualized depictions of human wildlife conflict might be best described as portraits. These drawings are large and done with graphite; as such they are perhaps best viewed in a gallery, museum, or up close and personal settin g. Their reduction and reproduction is hindered by their size, detail, and medium; they cannot be classified as scientific illustrations. Figure 1: Al look i nside the Chattahoochee Nature Center Wildlife Clinic. Photo taken by the author
4 Representational images conveyed by illustration are designed to be informative. They appeal to the human affin ity for visual learning, and their didactic function may be furthered by a closely related text. Scientific illustrations are commonly found in field guides, medical textbooks, self guided trail brochures, on informational markers along hiking trails, and in descriptive works on flora and fauna. When used correctly, scientific illustration is extremely useful as it has the capacity to convey selectively certain information as organized by the illustrator. Positioning an organism as to emphasize certain streaks of coloration necessary in identification, or arranging commonly confused yet independent organisms side by side these are some of the available tools the illustrator may readily employ in the task of informing the viewer. In contrast to other m edia, a single illustration may at once be direct, precise, and concise. As digital and digitally generated information becomes increasingly available, hand drawn scientific illustrations through their unique advantage and personal nature remain relevant. Finally, by the nature of their process, illustrations innately disclose an intimate relationship between object and illustrator, and provoke emotional response from the viewer. The first chapter of this thesis outlines and advocates the efficacy of hand drawn illustrations as an educational tool. Visual learning, the functions of illustration, and the role of the illustrator are explored. This chapter aligns the illustrations included in this thesis alongside those medical illustrations from the school of anatomical realism. This is done in terms of the means of visual description
5 and an adherence to the unadulterated image, including the portrayal of postmortem subjects in scientific illustration. Finally, an indication of the important role of rapto rs in the world of human art and cultural history is introduced. In the second chapter a declaration is made for the necessity of raptor conservation; both as superbly adapted organisms in their environment and ecologically as apex predators. This chapter explores the predatory adaptations of both the diurnal and the nocturnal bird of prey, and explains how these adaptations have enabled the raptor as an ecologically essential apex predator. The third chapter includes the illustrations and for each an acc ompanying textual explanation. Each portrait depicts a raptor whose life was ended on account of human interference. Through their exhibition for and explanation, I endeavor to raise an educated and emotional awareness of both the issues involved in huma n raptor conflict, and the awe inspiring nature of birds of prey.
6 CHAPTER I THE EFFICACY OF AND HUMAN AFFINITY FOR ILLUSTRATION Any natural form or event seen as worthy of examination will surely be illustrated by human hands. For example, the record of human illustration of animals extends at least as far back as 33,000 years. On the walls of the Chauvet cave in southern France, skillful depictions of animals such as horses, cave bears, hunting lions, and fighting rhinoceroses com pose the oldest discovered cave paintings (Clottes 2008; Figure 2). In 1610 Galileo Galilei, aided by his telescope, drew the first illustrations of craters on the surface of the moon, and in so doing conveyed by hand information otherwise invisible to the human naked eye. Similarly, the microscope and the pen that accompanied it allowed for the first acutely detailed illustration of a flea (Figure 3) and a discussion on its joints and armor in Robert Hooke's Micrographia, first published in 1665 (that publication also contained the first drawing and description of Fig. 2: The Panel of the Owl in the Chauvet Cave of southern France. Taken from Clottes 2008
7 the plant "cell", a term Hooke coined, from a cross section of cork) (Hooke 1665). Frederick II of Hohenstaufen's instructive thirteenth century illustrations from De Arte Venandi cum Avibu s illuminate an ancient partnership between human and raptor, the art of falconry (Figure 4). Posited by Ford (1993), one function particular to scientific illustration is that of capturing the state of human knowledge at an exact moment in time; this acc ess granted by scientific illustrations gain the viewer entrance into the deep and captivating halls of humankind's exploration into the world around it. Fig. 4 : Illustration f rom Frederick II's treatise o n falconry De Arte Venandi cum Avibus
8 The choice of illustration is utilit arian; before written language and symbols existed, the best way to describe an object was by its visual representation. Assuming the sense of sight to be operational, our eyes are our most immediate and useful means of gathering visual information, and t he human use of illustration is strengthened and supported by a shared affinity for learning visually. Indeed the visual style, or modality, of learning and recollection is dominant in the majority of adolescents and adults, and has likely always been so (Barbe and Milone 1981). Representational illustrations, or those that share a physical resemblance with the object pictured, may be used as effective tools for education; this is supported by research on the importance of providing examples when teachin g concepts (Alesandrini 1984). During lectures on heart anatomy, Dwyer (1967) found that representational illustrations in the form of realistic, shaded drawings of the heart aided in retention of relevant information better than did a strictly verbal lec ture, or a Fig. 3: Illustration of a flea aided by microscope, by Robert Hooke
9 lesson that included the use of color photographs of the subject. In cross modal learning, appropriate illustrations enhance the overall usefulness of verbal or textual information (Levin and Mayer 1993). One study conducted by Levin, Bender, and Lesgold (1976) demonstrated that children recalled a greater amount of verbal information when complemented by pictures than when asked to recall oral prose after it had been repeated twice without illustrations. Research conducted by Paivio and Csapo (1969) confirmed that presenting a concept once as a word and once as a picture was superior to presenting that concept twice as a word or twice as a picture. Illustrations attract and direct attention. Gaining attention is the first step in the learning process; it is imperative in introducing information to the short term memory, which may then be transferred into the long term memory bank through rehearsal (Atkinson and Shiffrin 1968). Illustrations also introduce complexity, novelty, and relief to a page, thus engaging the viewer and increasing the chances of affecting a learner's attitudes and emotions (Levie and Lentz 1982). Berlyne's (1966) notion that people tend to be attracted to things that are novel or dramatic is widely accepted, and support ed by studies showing that the first glance and more time will be given to images that are novel, incongruous, or unfamiliar. Novel and dramatic encounters themselves have the potential to arouse emotional response, and emotional arousal activates specifi c hormonal and brain system responses that regulate long term memory storage (Cahill and McGaugh 1998). This research lends support to the educational potential of the illustrations in this thesis, as the content depicted is of a novel, if not dramatic na ture. The unfamiliar postures of the subjects lend themselves to investigation by the viewer.
10 Illustrations can elicit emotional response by citing important conservation issues. A survey by Prelle and Solomon (1996) of 14 year old students in Germany an d England asked students to identify the three foremost environmental problems from a list of nine and explain their choices. Of the most common selections, "threats to wildlife" generated the most passionate responses. Explanations for the other two mos t popular choices, ozone depletion and rainforest destruction, were more factual in nature, although the information relied upon was commonly incorrect. In this case, a greater sense of empathy with wildlife coincided with a greater concern and motive for conservation. Finally, illustrations may provide additional information on a topic, and therefore accommodate learners who struggle with verbal and/or kinesthetic styles (Levie and Lentz 1982). Science has a long standing relationship with illustration in the presentation and explanation of natural subjects and phenomena. In science especially, visual images are preferred for displaying multiple relationships and processes that are difficult to describe by other means (Cook 2008). Indeed, Mayer (1993) found that fifty five percent of the total printed space in six science textbooks was devoted to the use of illustrations. Humans seek out illustration to capture their understanding of natural processes, thus building an ever greater hand drawn catalogu e of scientific knowledge and inquiry. Translated through illustration, the most unfamiliar or esoteric forms become approachable, familiar, and available to the student.
11 ANATOMICAL REALISM AND POSTMORTEM SUBJECTS IN SCIENTIFIC ILLUSTRATION As in this t hesis, the greater catalogue of scientific illustration is replete with the study and portrayal of postmortem organisms. The famous bird portraitist and conservation icon John James Audubon achieved the great detail of his illustrations in the iconic Bird s of America by shooting many of the subjects himself. As he recalls in the story of his first encounter with the "Caracara Eagle" ( Caracara cheriway ) in Florida, "Instead of going after [the Caracara] myself, I dispatched my assistant, who returned with it in little more than half an hour. I immediately began my drawing of it" (Proby 1974). Audubon also details a wince inducing account of his party's killing of Bald Eagle fledglings on the eighth of February 1832, along the St. John's River in Eastern F lorida: "We visited another nest, on which, by the aid of a telescope, we saw three young [Bald Eagles] ... The bird first shot fell back in the nest and there remained: it was struck by a bullet. The next was so severely wounded that it clung outside the nest, until fired at a second time, when it fell. The third was killed, as it was preparing to fly off. Our axes being dull, the tree large, and a fair breeze springing up, we returned to the [boat], where in a few hours these young birds were skinned, cooked, and eaten, by those who had been in at the death.' They proved good eating, the flesh resembling veal in taste and tenderness." (Proby 1974, 136 7)
12 The history of anatomical and medical illustration is also founded upon the use of animal carca sses and human cadavers. This is demonstrated to an obvious, if not startling degree in anatomical atlases such as Govard Bidloo's Anatomia Humani Corporis of 1685, or William Hunter's The Human Gravid Uterus in Figures of 1774. Prior to these publicatio ns, woodcuts from earlier anatomical studies portrayed their disemboweled models often posing atop a scenic hill, their otherwise able bodies captured in some classical aesthetic stance with their internal organs, musculature, or skeleton neatly displayed (Figure 5). But by the late seventeenth century, many anatomical illustrators had grown weary of the inclinations of the classical humanist, choosing instead to convey their subjects through a less stylized, more realistic image. Artists and anatomists h ad by this time come to be seen as at perpetual odds; the one striving for smoothness and elegance of form, the other for accuracy of representation, respectively (Bell 1794). As a result, some anatomists began making their own drawings, etchings and engr avings. Others replaced the landscaped backgrounds and aesthetic poses with stark, at times unsettling figures of subjects depicted in the contorted postures of their investigation. These scientists Fig. 5: From Andreas Vesalius's De Humani Corporis Fabrica Drawn by Jan Steven van Kalkar
13 and illustrators would come to be known as the "Anatomi cal Realists" of the late seventeenth and eighteenth century (nlm.nih.gov). With regard to their educational merit, the information contained in the unadulterated catalogue of the Anatomical Realists is doubly preparatory for the surgical student they illustrate precisely what to expect at an operating table. As John Bell explains in his Engravings of the Bones, Muscles and Joints : "Dissection is the first and last business of the student; and when drawings are made for his use, the body should be lai d out, as he is to order it in dissection; the belly should be displayed, as he can display it in his subject; an arm should be so drawn, that, when he dissects the arm of the subject, it may fall naturally upon the table, exactly as he finds it in his boo k" (Bell 1794, xi) Secondly, from an imagery and empathetic perspective these raw depictions lend themselves to an almost forced recollection; drawings from the school of Anatomical Realism have a tendency to impress themselves upon one's mind. Distur bing, yet masterful illustrations of dissected late term pregnancies were carried out by eighteenth century medical illustrator Jan Van Rymsdyk, as contracted by the Scottish anatomist William Hunter, founder of the field of obstetrics (Figure Fig. 6: An illustration of a cadaver dissected late in p regnancy, illustrated by Jan van Rymsdyk. Taken from William Hunter's The Anatomy of the Gravid Uterus in Figures
14 6). A total of thirty four plates were prepared for Hunter's The Anatomy of the Human Gravid Uterus in Figures first published in 1774 (Mitchell 1927). William Hunter had the good fortune, as he described it, to dissect a total of thirteen well preserved subjects a t various stages of pregnancy, and was able to record each endeavor through the encapsulating means of scientific illustration. Hunter was convinced that illustrations were an indispensable tool to science; "[Scientific illustration] conveys clearer ideas of most natural objects, than words can express; makes stronger impressions of the mind; and to every person conversant with the subject, gives an immediate comprehension of what it represents" (Hunter 1774). An historical perspective for the drawings of postmortem raptors in this thesis can be discerned along the same lines as those executed by scientific illustrators from the school of anatomical realism. Like those illustrations, the subject is illustrated precisely as observed, in this manner guiding the viewer toward a stronger understanding of what is being pictured. There is no sprucing up of the image; the peculiar postures and uncomfortable event conveyed by raptors that have died as a result of some adverse anthropogenic impact beg a deeper inv estigation. THE DEPICTION OF RAPTORS IN POPULAR CULTURE
15 The portrayal of raptors in illustration begins with the Paleolithic etching of an owl, identifiable by its beak, facial disk, and ear tufts over 30,000 years ago in the Chauvet cave of southern France. The owl's posture may suggest its head is turned a full one hundred and eighty degrees to face the viewer (Wheye and Kennedy 2008). In ancient Egypt, raptors, namely falcons and vultures, were revered as deities and depicted in sculptures, as rel iefs and illustrations on shrines, palaces, and tombs (Weidensaul 1996). Ancient Athenian tetradrachm coins were stamped with the profile of Athena on one side and an owl on the opposite; the obverse side of the Greek 1 Euro coin currently features the sa me image of an owl (Deacy 2008). In North America, raptors serve as idyllic symbols of power and freedom. A rising Bald Eagle, the only species of eagle entirely endemic to North America, figures prominently as the sole and central figure upo n our nation's Great Seal. The first design, finalized by William Barton and Charles Thomson, was adopted by Congress on June 20, 1782, five months before the end of the Revolutionary War (Figure 7) (Herrick 1934). Since becoming the United States of Ame rica's national bird, wrote Francis Herrick in his work The American Eagle (1934), the image of the Bald Eagle "probably has been more greatly multiplied and spread more widely Fig. 7: The First Great Seal of the United States of America, designed by William Barton and Charles Thomson. Taken from Herrick 1934
16 over the face of the earth than that of any other living being in the history o f the world". Raptors play a major part in Native American cultural history. The Iroquois Confederacy was represented by the depiction of an eagle perched atop a tree. Eagle figures are commonly carved into totem poles and represented in the formline art of the Pacific Northwest (Figure 8). In Cherokee creation mythology, mountains and valleys were created as a great vulture beat its giant wings too close to the new, soft earth (Mooney 1995). The Golden Eagle ( Aquila chrysaetos ) was especially prized, a nd was perhaps the most highly revered bird in the western continent (Weidensaul 1996). The black and white retrices of the immature Golden Eagle's are used in the familiar Plains style war bonnet, and served as the standard of value for the Blackfoot tri be before the arrival of the whites. For the Blackfoot, five Golden Eagles used to be worth a good horse (Grinnell 1962). Fig. 8 : Haida formline drawing of an eagle, by Freda Diesing
17 To obtain these prized animals, specialists would ceremoniously capture adult Golden Eagles. George Bird Grinnell founder of the first Audubon Society and an adopted member of the Blackfoot tribe of the Rocky Mountain region, recounted the pit trapping method of Golden Eagle capture as told by the famous eagle catcher John Monroe: "The pit is dug, six feet long, thr ee wide, and four deep, on top of the highest knoll that can be found near a stream. The earth taken out is carried a long way off. Over the pit they put two long poles, one on each side, running lengthwise of the pit, and other smaller sticks are laid a cross, resting on the poles. The smaller sticks are covered with juniper twigs and long grass. The skin of a wolf, coyote, or fox is stuffed with grass, and made to look as natural as possible. A hole is cut in the wolf skin and a rope is passed through it, one end being tied to a large piece of meat which lies by the skin, and the other passing through the roof down into the pit ... The eagle, sailing about high in the air, sees the bait, and settles down slowly. It takes a long time to make up its min d to come to the bait. In the pit, the man can hear the sound of the eagle coming. When the bird settles on the ground, it does not alight on the bait, but at one side of it, striking the ground with a thud -heavily. The man never mistakes anything el se for that sound. The eagle walks toward the bait, and all the other birds fly away. It walks on the roof; and, through the crevices that have been left between the sticks, the man can see in which direction the bird's head is. He carefully pushes the stick aside and, reaching out, grasps the eagle by two feet. The bird does not struggle much. It is drawn down into the pit, and the man wrings its neck. Then the opening is closed, and the roof arranged as before." (Grinnell 1962, 238 9) The intensity and extent of this activity exemplifies the degree to which these charismatic birds of prey are sought out for use in the human world. Not surprisingly, the body parts and feathers of eagles are still included in Native American religious ceremonies, al though their use is now prohibited without
18 legal permit. The National Eagle Repository in Denver, Colorado collects the bodies of Bald and Golden Eagles that have died as a result of electrocution, vehicle collision, unlawful shooting and trapping, or natu ral causes and redistributes them to enrolled members of Federally recognized Native American tribes. Native Americans cannot collect their own eagle feathers because these raptor's numbers have been so reduced by urbanization, exposure to chemicals used in agriculture and animal husbandry, and poaching ( www.fws.gov/le/Natives/EagleRepository.htm ). Eagles, however, are not the only species of raptor adversely affected by widespread anthropogenic impacts in America today.
19 CHAP TER II HUMAN RAPTOR CONFLICT The cultural and iconic value of raptors, their anatomical specialization, and their far reaching ecological importance as top predators are contributing factors in the justification of birds of prey as a nexus for focused con servation and education efforts. The recognition of past offenses to the raptor by human activities has earned birds of prey the benefit of protection by federal law(s) in the United States; either the Migratory Bird Treaty Act, the Bald and Golden Eagle Protection Act, or the Endangered Species Act. But because humans have put some of our nation's most remarkable birds of prey at risk, and anthropogenic causes remain a significant cause for raptor injury and death, the success of the raptor in the United States is uncertain. Human activities can and do have adverse affects on wildlife. Human wildlife conflicts, in which one of these species harms the other, may reflect a case of unintended or indirect human liability, as when an opossum is accidentally struck by a car on a roadway, or the may relate intentional involvement, as when a wolf is purposefully killed by a rancher in retaliation for a loss of domestic livestock. Humans and raptors come into conflict for a variety of reasons, but because of the behavior and habits of raptors dangerous intersections occur at certain junctures more than others. Collisions with automobiles and other structures, electrocution atop utility poles, poisoning and environmental contamination, and direct persecution are among the commonest anthropogenic agents for raptor injury and death in the United States.
20 KEYS FOR RAPTOR CONSERVATION: EVOLUTION AND ADAPTATIONS Raptors are a highly evolved group of avian predators whose fossil record dates back to the Eocene epoch, an d currently enjoy a pattern of nearly worldwide distribution, excepting Antarctica (Weidensaul 1996). Fifty three species of raptor live in the United States; in Florida 26 species occur, 18 of which breed here. The geographic breadth of the raptor may b e attributed in part to the effectiveness of its adaptations for hunting; all raptors possess a sharp, curved beak for tearing flesh, strong feet and curved talons for subduing prey. Owls, in addition, have a number of special adaptations specifically suit ed for hunting at night. New World vultures (the Black Vulture, Coragyps atratus and the Turkey Vulture, Cathartes aura ) are considered raptors, though technically they are not; their feet lack a strong rear toe, called a hallux, and they do not kill the ir own food. Phylogenetic evidence suggests a closer relationship of New World vultures to members of the order Ciconiidae, the storks (Avise et al. 1994). In terms of the defining characteristics of (most) raptors, the following physiological exploratio n is meant to create a better understanding of the specialized anatomy that makes the bird of prey so successful in the wild. THE DIURNAL RAPTOR Raptors are split roughly into two groups; diurnal and nocturnal. Diurnal raptors, represented by 34 specie s of bird of prey in North America, are the accipiters, buteos, eagles, kites, osprey, harriers, falcons, and New World vultures. With the
21 exception of the vultures, all are members of the Order Falconiformes. Their taxonomic Families are Accipitridae, P andionidae, Falconidae, and Cathartidae. All diurnal raptors rely heavily upon their eyesight for locating prey (claims to the Turkey Vulture's sense of smell remain unsubstantiated). The popular phrases "eyes like a hawk" or to "watch like a hawk" ref lect a popular acknowledgement of the raptors' prowess in this particular sensory capacity. One study by Walls (1942) deduced that the eyes of the hawk must be eight times as powerful as those of the human, based on estimates of cone cell density in the c entral fovea of the raptor, able to spot prey from up to a mile a way (Elliott 2008). The eyes of the raptor are proportionately very large relative to body size; they face forward (the eyes are even closer together in the owls), and are bordered above by an "eyebrow", really a pronounced superciliary ridge (Figure 9). These features allow for depth perception via binocular vision, but also tend to lend raptors a human like appearance. Larger raptors such as eagles and vultures actually have eyes similar in size to those of Homo sapiens, but comparatively exhibit better visual acuity. Snyder and Miller (1978) rated the optical strength of the falconiform at about 2.5 times greater than that of the Fig. 9: Superciliary ridge of a deceased Red Shouldered Hawk. Photo taken by the author
22 human eye, and without sacrificing image resolution. The beaks of raptors have likewise evolved to suit a common predatory function. Like all birds, the beaks of raptors consist of an internal bone structure covered with keratin, and are enlisted in typical activities such as grooming and preening. However for the birds of prey, the upper jaw, or maxilla, is curved downward, specifically suited for tearing the flesh of or killing preferred prey (Figure 10). As exhibited on the versatile Crested Caracara, this curve is relatively shallow; highly specia lized ra ptors such as the Hook billed Kite ( Chondrohierax uncinatus ) and Snail Kite ( Rostrhamus sociabilis ) exhibit more extreme designs. The Hook billed Kite and Everglade Snail Kite of the extreme southern United States are snail Fig. 10: The curved beaks of birds of prey as contrasted with the shorebird (b), the finch (d), and the duck (h ). Notice the elongated beak of the Everglade Snail Kite at (f), and the maxillary "tooth" of the American Kestrel Falcon, Falco sparverius, illustrated at (g) Illustration by L. Langelier
23 specialists; they use an elonga ted and sharply curved maxilla to extract the plump bodies of snails from their tough outer shells. Some raptors use their beaks to dispatch their prey completely; all falcons, excluding the caracara, have an additional specialized serration, or notch, on their upper mandible, called a "tooth". It is used to break the necks of avian or mammalian prey (Brown 1976). The Northern Pygmy Owl also uses its beak to snap the neck of its prey, although no discernible tooth is present (Dickson 2009). If the diu rnal raptors' eyes are instrumental in their location of prey, and the curved beak of the raptor is used to tear the flesh of the prey subdued, the raptor's hindlimbs constitute the raptors' superb weaponry crucial in that prey's seizure. The raptor's fee t and talons are their primary offensive and defensive force; when handling raptors, one must always take extreme precaution to avoid getting "footed", as the resulting injury can be great. When handling birds of prey, raptor rehabilitators commonly use t hick leather welding gloves, and special gloves reaching all the way up to the shoulder are preferred for handling eagles. In hunting, the feet and talons work together; the long, sharp talons penetrate and grasp prey, while the tremendous grip of the fo ot and its internal network of Fig. 11: Closed foot of the Red Tailed Hawk, Buteo jamaicensis. P hoto taken by the author
24 tendons are capable of exerting enormous pressure on the victim's body (Figure 11). This combination is often enough to create a fatal injury. In a grasping event, raptors either directly close the foot by contracting flexo r muscles along the posterior of the tibiotarsus, or contracting the tibialis cranialis, which in turn flexes the intertarsal joint and pulls tendons taut. When the tendons are pulled tight within their encompassing tendon sheath, the foot is closed and l ocked it with a sort of internal "ratcheting system", generating greater pressure and driving talons deeper into prey than could be achieved by muscle contraction alone (pers. comm. Jim Solomon; Ward et al. 2002). Owls are capable of exerting greater for ce with their feet than are similarly sized falconiformes. An adult Bald Eagle can exert upwards of 400 pounds per square inch with each foot, about 10 times that of an adult human hand. A Great Horned Owl ( Bubo virginianus ) half that size can exert a gr ip pressure of up to 500 pounds of pressure per square inch (Figure 12). The Great Grey Owl ( Strix Fig. 12: The weathered feet and talons of a deceased Great Horned Owl. Photo taken by the author
25 nebulosa ), hunting in winter, can plunge feet first into a snow crust capable of supporting a 180 pound person (Warren 2005). STRIGIFORMES Members of the order Strigiformes have evolved adaptations that make them deadly nighttime hunters. Additional adaptations unique to the ears and feathers have evolved, allowing owls to hunt successfully in low or no light conditions during wh ich their crepuscular and nocturnal prey are most active. Efficient advancements to the auditory faculties of the strigiform are perhaps their most remarkable adaptations; the owl's characteristic facial disk is the most noticeable of these (Figure 13) A circular arrangement of feathers on the front of the owl's face that traps sound and funnels it toward the ears, the facial disk acts as a satellite dish for amplifying sound. Hidden beneath feathers, the external ear openings receiving these vibrati ons represent another effective adaptation. Depending on the species, the ears of some Fig. 13: The distinct facial disk of the Barred Owl, Strix varia Photo taken by the author
26 owl species are positioned asymmetrically on the owl's head, in which one ear is located above the other. Asymmetry creates a unique stereophonic system of "binaural" sound reception, with which the owl is able to pinpoint the exact location of a potential prey item, even in complete darkness (Johnsgard 2002). This feat, first documented in Barn Owls ( Tyto alba ) by Roger Payne, is accomplished presumably by the detecti on of differences in the relative intensity of sound in each ear as they vary with the angle at which the vibration is received (Payne 1971). Successful hunting in complete darkness has since been observed in other predominantly nocturnal owls, such as th e Saw whet Owl ( Aegolius acadadicus ), Great Gray Owl ( Strix nebulosa ), and Long eared owl ( Asio otus ) (Snyder 2006). For species of owl heavily reliant on hearing to locate and capture their prey, noise reducing adaptations to flight and foot feathers ha ve likewise evolved. Comb like serrations at the leading edge of the wing, fringed feathers at the trailing edge of the wing, and exposed down feathers on the wings and feet all conspire to keep the noise level of the owl during flight below 2 kHz, beneath the audible range typical prey items such as mice and voles (Lilley 1998). Less noise means reduced interference with the owls' tracking abilities, and a heightened element of surprise. KEYS FOR RAPTOR CONSERVATION: THE RAPTOR AS AN APEX PREDATOR The impressive anatomical adaptations that make the raptor such a successful hunter in the wild likewise serve a critical function within the ecosystems raptors inhabit. As apex predators, raptors have been described as keystone species exerting
27 a profound st ructural influence within their biological communities (Davic 2003; Wallach et al. 2009). As top predators raptors put pressure on prey behavior, are responsible for trophic cascades, mediate mesopredator release, facilitate resource availability, and pro mote overall biodiversity (Ritchie and Johnson 2009; Sergio et al. 2005, inter alia ). At the top of the food chain raptors are also particularly susceptible to environmental change and contamination, persecution, and competition; they are indicator specie s of both environmental health and human attitudes (Movalli et al. 2008). Dramatic and potentially disastrous effects, such as rapid onset secondary extinctions and/or mesopredator release, occur when top predator populations collapse or are eliminated ( Borrvall et al. 2000; Prugh et al. 2009). When top predators recover or are reintroduced into ecosystems, they are associated with ecological restoration (Ripple and Breschta 2003). The most direct way top predators affect the biological communities in which they operate is by removing individual prey items from a given population via predation. This "direct lethal effect" involves both direct predation and the series of consequent ecological events (Schmitz et al. 1997). In response to the direct leth al effect of top predators, prey species alter their behavior in order to minimize the risk of predation. These behavioral changes are called "nonlethal indirect effects" and are perhaps even more significant than the effect direct predation has on prey p opulations (Lima 1998). Both lethal direct effects and nonlethal indirect effects are responsible for trophic cascading, or successive events occurring along lower trophic levels (Ripple
28 and Beschta 2003). For example, the recovery of the Peregrine Falc on, once decimated by dichlorodiphenyltrichloroethane ( DDT) contamination along America's northwestern coast, has altered the migratory route and stopover time of avian prey species Calidris mauri the Western Sandpiper; this change then influences populat ions of insects, small crustaceans, and mollusks that the Western Sandpiper feeds on, and eventually affects factors such as seasonal herbivory of the sandpiper's insect prey species (Ydenberg et al. 2004). The top down influence of top predators may also be measured in corresponding terms of overall species biodiversity. In an early study of food webs by Paine (1966), the removal of the top predator starfish Pisaster ochraceus along a typical stretch of shoreline in Washington led to increased colonizati on of available habitat by barnacle species, consolidating the biological profile and inhibiting species diversity. More recently, Sergio and colleagues (2005) found that different areas representing varied habitats inhabited by five different species of raptor exhibited consistently greater numbers and higher diversity of avian species, butterfly species, and tree species than those areas dominated by middle trophic level predators such as insectivores and herbivores. When influential top predators are r educed in or removed from an operating ecological system, once balanced structures teeter precariously. Loss of an apex predator can trigger precipitous dips in the numbers of species further down the food chain, even secondary extinction events (Borrvall et al. 2000). Steep declines in numbers of prey species resulting from the absence of apex predators have been attributed to "mesopredator release", a phenomenon documented in a range of
29 habitats (Prugh et al. 2009). Mesopredator release occurs when mes opredators are allowed to flourish beyond their otherwise sustainable level; these intermediate predators are normally suppressed by apex predators to reduce competition for resources (Ritchie and Johnson 2009). For example, In Sub Saharan Africa the hunti ng of lions and leopards and those cats' subsequent decline has led to an explosion in numbers of the Olive Baboon ( Papio anubis ). The rise of this mesopredator has in turn led to detrimental effects on populations of wild ungulates (hoofed animals), and even forced parents to keep their children home from school to defend their fields against brazen crop raiding baboon troops (Prugh et al. 2009; Brashares et al. 2010). In the now classic case study of the Grey Wolf ( Canis lupus ), reintroduction of a top predator species was positively correlated with nonlethal indirect effects of prey species, a boost in overall species diversity, and a reversal of mesopredator release. By the 1920's, fierce predator eradication programs extirpated the Grey Wolf from mu ch of its historic range in the lower 48 United States (Leonard et al. 2005). After 70 years of virtual absence in the Rocky Mountain region of the American Midwest, the Grey Wolf was reintroduced into Yellowstone National Park in the winter of 1995 1996. The wolves' renewed presence had a profound effect on the local trophic community. In one example, under the renewed threat of predation elk altered their foraging patterns, allowing stands of willow, cottonwood, and aspen plant species to mature along vulnerable streambeds. This in turn stabilized stream banks and riparian zones, and a food supply of older trees allowed for beaver colonies to flourish; the dams beavers build provide habitat for fish, amphibians, birds, small
30 mammals, and insects (Chadw ick 2010). Because of intraguild predation, or the persecution by a top predator of a mesopredator, the coyote's numbers were reduced, and this may be a factor in the pronghorn's local resurgence (Holt and Huxel 2007; Chadwick 2010). Increased availabili ty of uncovered carrion by the wolves has facilitated resource availability for scavengers reliant on harsh winter weather related carcasses, those in short supply given the milder winters of a changing (Sala 2008; Figure 14).
31 HUMAN RAPTOR CONFLICT: DIRECT PERSECUTION Top predator conservation and restoration have obvious ecosystem benefits, but such efforts are often met with resistance. The basis for persecution of apex predator Fig. 14: Illustration juxtaposing biod iversity in Yellowstone National Park ecosystem where wolves are absent (left) and present (right). Illustration taken from Chadwick 2010
32 species, including raptors, often coincides with a perception of t op predators as competition for food resources (Prugh et al. 2009). Raptors have probably been viewed as nuisance animals since the dawn of stock farming, despite greater threats posed to livestock and game populations by hunger and disease (Brown 1976). Predators naturally disperse their hunting efforts, and precautionary measures further lessen the impact that raptors have on prey populations (Weidensaul 1996; Kenward 1999) I have seen numerous x rays taken of a hawk or owl whose i nsides are littered with the telltale small round dots of a shot or BB gun. Twenty one raptors admitted to the Audubon Center for Birds of Prey in 2007 suffered definite or probable gunshot wounds, as was the case with at least 16 raptors admitted in 200 8. The Fig. 15: A 1932 photograph shows shot hawks lined up along Kittatinny Ridge, Pennsylvania. Photo taken from Weidensau l 1996
33 Chattahoochee Nature Center in Roswell, Georgia took in 15 gun shot raptors from 2006 through present. Wildlife Center of Venice director Kevin Barton speculated that most local direct persecution of raptors goes on east of I 75, but his facility has encountered numerous blowgun and dart injuries. Despite their protection provided by the United States Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act, shooting continues to be the leading cause of death for juvenile Bald Eagles (Weidensaul 1996). Because it is a violation of federal law to shoot a raptor, gunshot incidents are reported by wildlife rehabilitators to the United States Fish and Wildlife Service, and the cadavers kept for evidence in case of a criminal trial. Th ese cases must first, however, be reported. Reports of gunshot wounds have been steadily declining in birds of prey, but as illustrated even at a local level there are incidents. HUMAN RAPTOR CONFLICT: "INCIDENTAL TAKE" Indirect anthropogenic sources of injury and death currently constitute a "primary threat to raptor populations" (Richardson and Miller 1997). Such sources of trauma constitute the majority of identifiable sources of recorded raptor mortality and morbidity year round, and species of rapt or occurring in North America are affected (Wendell et al. 2002; Hager 2009). While urbanization and human development have created new niches and favorable conditions for certain species of wildlife (many species of raptor, such as Kestrel Falcons, Pereg rine Falcons, Osprey, Bald Eagles, and Red Tailed and Red Shouldered Hawks, are known to make use man made structures for hunting, perching, and nesting), the associated risk of the modern
34 American environment to raptors is evident (Hadidian and Smith 2001 ). ROADWAYS The increasingly dense network of roadways in America adversely effects wild raptor populations via habitat fragmentation, isolation, increased air and water pollution, noise pollution, and direct mortality (Glista et al. 2008; Bautista et a l. 2004). In an early quantitative study on roadkill, Stoner (1925) added "the mania for speed so prevalent among automobile drivers" to that list. Two years later, Sutton (1927) concluded that 82 out of 113 dead Eastern Screech Owls ( Otus asio ) collecte d over three years on roadsides in Pennsylvania were killed by cars. From March 2000 until March 2010, the Chattahoochee Nature Center in Roswell, Georgia received 297 raptors hit by cars (pers. comm. Kathryn Dudeck). Raptors are drawn to roadways for mu ltiple reasons. In general, roadways may represent areas of significant wildlife activity, especially by those species typical of habitat edges and open areas (Bautista et al. 2004). One study by Getz and colleagues (1978) found roadways to be well used corridors by at least one important raptor prey species, the meadow vole ( Microtus pennsylvanicus ). Cold blooded reptiles gather atop the relatively warm asphalt as the nighttime temperature drops. As both diurnal and nocturnal raptors converge upon road ways to hunt these types of prey, the risk of a collision with an automobile is at its greatest. Even higher is the risk posed to juvenile raptors, inexperienced with moving vehicles (Postelli 2000). When prey is spotted, a raptor becomes entirely focuse d in its pursuit, oftentimes flying low and swift. A five pound Great Horned Owl descending upon its prey is no
35 match for a 5,000 pound automobile moving at 50 miles per hour. During the day, the carnage wrought by automobiles attracts vultures and other carrion eaters to feed, and they are at risk of becoming roadkill as well. One final reason raptors are drawn to roadways is in the search for perching and nesting sites, offered by utility poles; these present their own set of dangers. ELECTROCUTION O f the 31 species of diurnal raptor and 19 species of owl that regularly breed in North America, 29 have been reported as victims of electrocution (Avian Powerline Interaction Committee 2006). Biological, environmental, and engineering elements all contribu te to these incidents; because of their size, hunting strategies, and nesting preferences, raptors are particularly vulnerable to electrocution atop utility structures. An electrocution event occurs when a raptor becomes a conduit for electric current. This happens when different body parts of a raptor, i.e. one of its wings and its tail, span the gap between two or more electrified elements, or an electrified Fig. 16: An electrocuted Red Shouldered Hawk ( Buteo lineatus ). Photo taken by the author
36 element and a ground. On a distribution power line, this can easily occur between two phase co nductors, a phase conductor and a neutral material (such as a wood pole), or a phase conductor and a ground wire. Distribution poles are typically constructed with less than 60 inches of clearance between electrified elements; the typical wingspan of a Go lden Eagle is 78 to 90 inches (Williams 2000; peregrinefund.org). Behaviorally, many raptors are sit and wait, or perch hunters; this is perhaps the most common hunting technique used by birds of prey (Weidensaul 1996). Saving the amounts of energy used i n soaring or aerial pursuit while taking advantage of their strong eyesight, perch hunting raptors prefer high perch sites with unobstructed views to locate prey; from a vantage point atop a utility pole a raptor waits for its next meal to come into its fi eld of vision or hearing, and then descends. In an otherwise un forested area, power lines afford these unobstructed vistas, and in contrast studies have shown that forested areas generally have fewer reported raptor electrocutions than do open habitats ( Switzer 1977; Benson 1981). In addition to sites for hunting, raptors employ utility poles for roosting, feeding, and nesting. Utility structures can provide nest stability, protection from mammalian predators, and nesting substrates where natural si tes are scarce; these factors can in some cases contribute to improved nesting success (Avian Powerline Interaction Committee 2006). Fledgling raptors, for example, prefer the stationary perches offered by utility poles for their short perch to perch pract ice flights; these benefits, however, result in increased incidents of springtime electrocutions (Harness 2000).
37 Modifications and retrofits to utility poles such as increasing clearances between conductors and ground wires, insulating energized components managing perching opportunities on power poles, and gapping ground wires reduce raptor electrocution (Lehman 2001). Local power provider Tampa Electric Company (TECO) recently completed its five year "Avian Protection Program", which identified and retr ofitted and/or reconstructed almost 1,200 "high risk" poles within their service territory, at an approximate cost of $800,000 (Tampa Electric ... [updated 2010]). Beyond the loss of life, incentives for power companies to modify utility structures includ e the cost of damage to equipment, power outages, and the penalty of federal offense. In 2009, the "incidental take" of raptor electrocutions became federally recognized as a violation of federal laws protecting raptors. WIND TURBINES An upcoming e nergy source threatens to pose increasing problems for raptors, migratory birds, and bats. Wind power is in growing demand in America, and it is estimated that on average each wind turbine kills .03 birds of prey every year, or roughly one raptor death fo r every 30 wind turbines (Marris and Fairless 2007). Wind turbine collisions in the Altamont Pass Wind Resource Area, California are responsible for raptor fatalities estimated to number in the "thousands" annually (Smallwood and Karas 2009). Location is a big part of the problem; the strong winds that blow over high, open ridges are choice locations wind farms, and are also preferred by raptors soaring on thermal updrafts.
38 In both the south and northeastern United States, power companies are looking o ffshore to generate wind power. In 2007, Florida Power and Lighting (FPL) proposed construction of the first wind farm in Florida in the form of six wind turbines erected off the east coast of Hutchinson Island in St. Lucie County. FPL abandoned the plan however, in response to both local opposition, and the Florida Fish and Wildlife Conservation Commission's claims that cited the offshore turbines' potential to disturb the behavior and nesting habits of species such as the threatened Loggerhead Sea Turt le ( Caretta caretta ) and the endangered Green Sea Turtle ( Chelonia mydas ) (Shudes 2008). It remains to be seen whether taller turbines with fewer blades, increased spacing between turbines, and greater attention to location will mitigate the toll wind turb ines current have on wildlife. POISONING AND BIOMAGNIFICATION The biological accumulation of toxins reaches its highest, and most dangerous, levels in long lived organisms and top predators (a phenomenon which "most people don't get", according to Gail St raight, owner of Wildlife, Inc., an Anna Maria Island based rehabilitation and education facility) (Hopkins, et al. 2007). Biomagnification occurs across trophic levels, as persistent toxins are passed from prey up to predator and accumulate faster than t hey can be metabolized. This results in higher concentrations of toxins in higher level predators over time. Raptors are threatened by the biomagnification of lead, mercury, organochloride compounds, and other potentially harmful chemicals widely in use.
39 Lead bullets take an additional toll on raptors and other wildlife through poisoning, as toxic fragments from spent ammunition are ingested by raptors feeding on the carcasses or discarded gutpiles of animals killed with lead ammunition. The intoxicating effects of ingested lead affect all bodily systems, and include neural degeneration, modification of kidney structure and bone, and inhibition of blood formation and nerve transmission (Pokras and Kneeland 2009; Hunt, et al. 2009). With regard to scaveng ing, a retrospective study of lead poisoning in Bald Eagles in Minnesota, Wisconsin, and Iowa correlated the incidence of lead poisoning with deer hunting season (Redig, et al. 2008). Lead poisoning has been detrimental to Golden Eagles and avian scavenge rs such as the California Condor as well. Lead intoxication nearly claimed the remaining remnants of the wild California Condor population before they were whisked away for captive breeding programs in the late 1980s, and lead poisoning is still consider ed the primary obstacle for the California Condor's recovery in the wild (Graham 2000; U.S. Geological Survey 2009). Mercury is believed to be one of the most significant pollution hazards to wildlife in the southeastern United States, especially within aq uatic ecosystems such as coastal wetlands along the Gulf of Mexico (Facemire et al. 2007). Atmospheric deposition contributes to overall environmental mercury levels, but mercury is also introduced into the environment through alkali and metal processing, incineration of coal, medical waste, and mercury and gold mining (U.S. Geological Survey 2000). Once in the environment, methylmercury, the most toxic form of mercury, readily accumulates in fish. Larger fish tend to accumulate higher levels of mercury than
40 smaller fish, and large fish are selectively preyed upon by large, fish eating birds of prey such as Osprey and Bald Eagles (Hopkins, et al. 2007). Prior to the publication of Rachel Carson's pivotal Silent Spring in 1962, and the ban of DDT (dichlo rodiphenyltrichloroethane) in the United States in 1972 (excepting the event of a public health emergency), bioaccumulation of organochloride pesticides was responsible for eggshell thinning, and subsequent widespread reproductive failure of Peregrine Falc ons, Osprey, and the southern Bald Eagle ( Haliaeetus leucocephalus washingtoniensis ) within the United States. These raptors primarily feed on birds and fish, suggesting the pesticide's (and its metabolites DDE and DDD) pathway through insects up to insec tivorous birds, and into waterways and marine organisms via agricultural runoff. For many years, migrating birds were still at risk of DDT exposure, until Canada completely banned the use of DDT in 1985, and successful alternatives for malaria control pro mpted the discontinuation of DDT use in Mexico in 2000 (Commission for Environmental Cooperation of North America 2003). Called the "new DDT", widely used polybrominated diphenyl ether (PBDE) flame retardants pose a threat to the reproductive success of at least the Osprey and American Kestrel Falcon by eggshell thinning, and have the potential to bioaccumulate in top predators (Chen 2009; Fernie et al. 2009). PBDE contamination in the environment represents a troubling new area of human wildlife conflict, as long term use of PBDE flame retardants has resulted in their "ubiquitous" presence in the environment and biota (Fernie et al. 2009).
41 Biomagnification results in secondary poisoning events when scavenging raptors feed on carcasses dispatched by toxic c hemicals. Wildlife, Inc. last year reported numerous cases of Cooper's Hawks that had probably been poisoned feeding on the dead bodies of poisoned rodents (pers. comm. Gail Straight). Secondary barbiturate poisoning is a big problem for Bald Eagles scav enging on euthanized pets in Florida landfills and in the western United States, where vultures and Golden Eagles feed on euthanized livestock left to lie out (pers. comm. Kathryn Dudeck; Milius 2006). OTHER SOURCES The list goes on as to the ways rapt ors are adversely affected by human activities; additionally, many raptors arrive at rehabilitation clinics suffering from a trauma whose cause cannot be identified. Common activities such as tree trimming and snag removal for instance eliminate perch, ne sting, and roosting sites for raptors and other wildlife. Sugar farming, introduction of exotic species, and the altered hydrology of the Florida Everglades have all conspired against the success of the Snail Kite (Cattau et al. 2010; Cubie 2007). The hu man endeavor toward action should always consider the potential for detrimental effects to wildlife beforehand, and proceed with caution. Falconry represents an interesting grey area within the relationship existing between raptors and humans. As is the c ustom with this ancient sport which is at least 4,000 years old and has been practiced in the United States since at least the 1920s, raptors are legally captured from the wild or obtained by captive breeding, and
42 used for hunting; but because participatio n in falconry in the United States is limited, and because nearly half the raptors used in the sport are produced through captive breeding, falconry is deemed as "very unlikely to have a significant adverse impact on wild raptor populations in the United S tates" (Millsap and Allen 2006). These results may also be considered in light of the generalization that along with the sporting demands placed on raptors in the practice of falconry, it is a reverence for these fine birds and their hunting abilities tha t strictly enforces their preservation. STEWARDSHIP Humans, using the means of self examination and investigation, can evaluate their behaviors as a group; through this process we have identified the ways in which humans affect birds of prey adversely. There is an argument that an animal species is valuable insofar as it benefits humans for example, the United States Fish and Wildlife Service states that its mission is "working with others to conserve, protect, and enhance fish, wildlife, plants and t heir habitats for the continuing benefit of the American people" (fws.gov). This anthropocentric notion of an animal's "benefit" to people may seem overly biased but if we can educate each other, continue our investigation into causes and effects, and u se our existing knowledge, the importance of wildlife preservation efforts and the knowledge that preservation of wildlife species is indeed of immeasurable benefit to humans becomes increasingly apparent.
43 CHAPTER III As an illustrator my role is t o representatively convey my observations of nature, which in this thesis involves raptors adversely affected by humans. Personal experience has guided my choice of these subjects; it is my intention that the illustrations reflecting upon this experience will incite interest, inspire concern in, and ultimately educate others. To the audience whom the written portion of this thesis may reach, the topics discussed herein may provide a ground upon which one may choose act, and further inform themselves on th e rich subjects of scientific illustration, effective education, raptor biology, predator ecology, and causes and solutions for human wildlife conflict. Within the intended scope of this thesis, education was recently explained to me as the act of "changi ng behaviors". I see the educational purpose of this thesis as just that; through this work I endeavor to generate greater respect and involved stewardship for the magnificent birds of prey. ILLUSTRATIONS: Turkey Vulture, Cathartes aura : This raptor was received by the Chattahoochee Nature Center in the spring of 2009. It arrived alive, but with a broken right humerus; according to the person who brought the vulture in, the bird had been hit by a car, and was then attacked by a dog in someone's front ya rd. In accordance with raptor rehabilitation guidelines and the difficulty, time, and resources in repairing compound fractures to humeri the Turkey Vulture was euthanized.
45 Cooper's Hawk, Accipiter cooperii : This immature female Cooper's Hawk was rec eived by the Chattahoochee Nature Center on the evening of December 15, 2008. On that winter evening, all had left the clinic except for myself and Brian Baker, a close friend, but a new hire at the clinic. We knew that the hawk was coming, and were entr usted to handle the bird its triage and so forth yet I daresay we were emotionally prepared for what we were about to do. When the Cooper's Hawk arrived, Brian and I were informed that the hawk had been hanging out in a stairwell inside a parking gara ge for the past few days, until somebody decided something needed to be done and caught the bird. When we received the Cooper's Hawk that night, she was fully alert; eyes open, mouth open and panting in the typical manner of birds that are stressed. We b egan examining the bird, and soon discovered an open wound in the bird's right upper breast; her clavicle had been shattered. As we examined the hawk's body further, we located another smaller wound, in her right abdomen. We decided that this was in fact an entrance wound, and that the Cooper's Hawk was shot. This resilient bird had not been killed upon the bullet's impact, or died during the next few days of trauma; but the wound was beginning to smell of infection, and her eyesight was failing in one e ye. Faced with an extremely tough decision that we made together, Brian and I euthanized the Cooper's Hawk that night.
47 Red Tailed Hawk, Buteo jamaicensis : Another victim of a bullet, this immature Red Tailed Hawk was photographed at the Chattahoochee Nature Center during the summer of 2009 and subsequently illustrated during that fall.
49 Bald Eagle, Haliaeetus luecocephalus : This adult female Bald Eagle was found in a front yard in Seminole County, Florida, suffering from severe head trauma, torticol lis, and seizures; the injury was most likely a car hit. The eagle was rescued by Seminole County Animal Services and brought to the Audubon Center for Birds of Prey in Maitland, Florida, where she was euthanized due to the extent of the trauma.
51 Works Cited Alesandrini KL. 1984. Pictures and Adult Learning. Instructional Science. 13: 63 77. Atkinson RC, Shiffrin RM 1968. Human memory: A proposed system and its control processes. In: Spence, KW, Spence JT. The psychology of learning and motivation (V olume 2). New York (NY): Academic Press. p. 89 195. Avian Powerline Interaction Committee (APLIC). 2006. Suggested Practices. Washington, D.C. Avise JC, Nelson WS, Sibley CG. 1994. DNA sequence support for a close phylogenetic relationship between some s torks and New World vultures. Proceedings of the National Academy of Sciences. 91:5173 5177. Barbe WB, Milone WM Jr. 1981. What We Know About Modality Strengths. Educational Leadership. p. 378 380. Bautista LM, Garcia JT, Calmaestra RG, Palacin C, Martin CA, Morales MB, Bonal R, Viuela J. 2004. Effect of weekend road traffic on the use of space by raptors. Conservation Biology. 18(3):726 732. Bell J. 1794. Engravings of the Bones, Muscles, and Joints. Edinburg: J. Patterson. Benson PC. 1981. Large rapt or electrocution and power pole utilization: a study in six western states. Ph.D. dissertation. Bringham Young Univ.. Provo, UT. p. 98. Bidloo G 1685 Anatomia humani corporis Amsterdam : Someren, Dyk, Hendrick & Boom Borvall C, Ebenmann B, Jonsson T. 2000. Biodiversity lessens the risk of cascading extinctions in model food webs. Ecology Letters. 3:131 136. Brashares JS, Prugh LR, Stoner CJ, Epps CW. 2010. Ecological and conservation implications of mesopredator release. In Terborgh J, Estes JA, eds. Trophic Cascades. Island Press. Forthcoming. Brown L. 1976. Birds of Prey: Their Biology & Ecology. Middlesex, England: Hamlyn Publishing Group Limited. Cahill L, McGaugh JL. 1998. Mechanisms of emotional arousal and lasting declarative memory. Trends in Neuroscience. 21(7):294 299.
52 Cattau CE, Martin J, Kitchens, WM. 2010. Effects of an exotic prey species on a native specialist: Example of the snail kite. Biological Conservation. 143(2):513 520. Causes of Injury to Wildlife [Internet]. [updated 2008]. Alabama Wildlife Center. [cited 21 February 2010]. Available from http://www.awrc.org/causes%20of%20injury.htm Chadwick DH. 2010. Wolf Wars. National Geographic. 217(3):34 55. Conover M. 2002. Resolving Human Wildlife Conflicts: the science of wildlife damage management. Boca Raton (FL): CRC Press LLC. Cook M. 2008. Students' comprehension of science concepts depicted in textbook illustrations. Electronic Journal of Science Education. 12(1):1 13. Clottes J. 2008. Cave Art. New York (NY): Phaidon Press Limited. Cubie D. 2007. Are these kites headed for a fall? National Wildlife. 45(1):18 20. DDT no longer used in North America. Commission for Environmental Cooperation of North America, Montral, Canada. April 2004. Davic RD. 2003. Linking keystone sp ecies and functional groups: a new operational definition of the keystone species concept. Conservation Ecology. 7(1):11. Deacy. 2008. Athena. New York (NY): Routledge. Dickson T. 2009. Tiny terror of the skies. National Wildlife. 47(4):34 39. DiSilver stro RL. 1996. What's killing the Swainson's Hawk? International Wildlife. 26:38 43. Dwyer F M. 1967. The relative effectiveness of varied visual illustrations in complimenting programmed instruction. The Journal of Experimental Education. 36(2):34 42. E lliott JE, Birmingham AL, Wilson LK, McAdie M, Trudeau S, Mineau P. 2008. Fonofos poisons raptors and waterfowl several months after granular application. Environmental Toxicology and Chemistry. 27(2):452 460. Elliott L. 2008. Soaring hunters: eagle hunti ng. Children's Digest. 58(2):4. Facemire C, Augspurger T, Bateman D, Brim M, Conzelmann P, Delchamps S, Douglas E, Inmon L, Looney K, Lopez F, Masson G, Morrison D, Morse N, and Robison A. 1995. Impacts of mercury contamination in the southeastern United States. Water, Air, and Soil Pollution. 80:923 926.
53 Fernie KJ, Shutt JL, Letcher RJ, Ritchie IJ, Bird DM. 2009. Environmentally relevant concentrations of DE 71 and HBCD alter eggshell thickness and reproductive success of American Kestrels. Environmental Science Technology. 43:2124 2130. Ford B. 1993. Images of Science: A History of Scientific Illustration. New York (NY): Oxford University Press. Frederick II. 1943. The Art of Falconry being the De Arte Venandi Cum Avibus of Frederick II Hohenstaufen. Stanford (CA): Stanford University Press. Getz LL, Cole FR, Gates DL. 1978. Interstate roadsides as dispersal routes for microtus pennsylvanicus. Journal of Mammalogy 59:208 212. Glista DJ, DeVault TL, DeWoody JA. 2008. A review of mitigation measures f or reducing wildlife mortality on roadways. Landscape and Urban Planning. 91:1 7. Graham F. 2000. The Day of the Condor. Audubon Magazine. January Febuary: 46 53. Grinnell GB. 1962. Blackfoot Lodge Tales. Lincoln (NE): University of Nebraska Press. p. 23 6 240. Hadidian J, Smith S. 2001. Urban Wildlife. In: Salem DJ, Rowan AN. editors. The State of the Animals 2001. Washington, D.C: The Humane Society Press. Hager SB. 2009. Human Related Threats to Urban Raptors. Journal of Raptor Research. 43(3):210 22 6. Herrick FH. 1934. The American Eagle: A Study in Natural and Civil History. New York (NY): D. Appleton Century Company. Hopkins WA, Hopkins LB, Unrine JM, Snodgrass J, Elliot JD. 2007. Mercury concentrations in tissues of Osprey from the Carolinas, U SA. Journal of Wildlife Management. 71(6):1819 1829. Holt RD, Huxel GR. 2007. Alternative prey and the dynamics of intraguild predation: Theoretical perspectives. Ecology. 88(11):2706 2712. Hooke R. 1665. Micrographia: Or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon. London: Royal Society. Hunt G, Burnham W, Parish C, Burnham B, Mutch B, Oaks JL. 2009. Bullet fragments in deer remains: implications for lead exposure in scavengers. In: Watson RT, Fuller M, Pokras M, Hunt WG, editors. Ingestion of Lead from Spent
54 Ammunition: Implications for Wildlife and Humans. The Peregrine Fund, Boise, Idaho, USA. Hunter W. 1774 The Anatomy of the Human Gravid Uterus E xhibited in Figures. Birming ham: Baskerville Press Johnsgard P. 2002. North American Owls: Biology and Natural History. Washington D.C.: Smithsonian Institution Press. Keller J Burkman E. 1993. Motivation Principles. In: Fleming M, Levie W H, editors. Instructional Message Des ign, Principles from the Behavioral and Cognitive Sciences. 2nd ed. Englewood Cliffs (NJ): Educational Technology Publications. p. 46. Kenward RE. 1999. Raptor predation problems and solutions. Journal of Raptor Research. 33(1):73 75. Lahner LL, Franson JC. 2009. Lead Poisoning in Wild Birds: Fact Sheet. U.S. Geological Survey National Wildlife Health Center. Lehman RN, Kennedy PL, Savidge JA. 2001. The state of the art in raptor electrocution research: A global review. Biological Conservation. 136(2):15 9 174. Leonard JA, Vil C, Wayne R K. 2005. Legacy lost: genetic variability and population size of extirpated US grey wolves ( Canis lupus ). Molecular Ecology. 14:9 17. Levie WH, Lentz R. 1982. Effects of text illustrations: A review of research. Educat ional Communication and Technology. 30(4):195 233. Levin JR, Bender BG, Lesgold AM. 1976. Pictures, repitition, and young children's oral prose learning. Audio Visual Communication Review. 24:367 380. Levin JR, Mayer RE. 1993. Understanding illustrations in t ext. In: Britton BK, Woodward A, Binkley M, editors. Learning from Textbooks: Theory and Practice. Hillsdale (NJ): Lawrence Erlbaum Associates. p. 95 113. Lilley GM. A study of the silent flight of the owl. In: 4th AIAA/CEAS Aeroacoustics Conference; 1998. Lima SL. 1998. Nonlethal effects in the ecology of predator prey interactions. Bioscience. 48(1):25 34. Marris E, Fairless D. 2004. Wind farms' deadly reputation hard to shift. Nature. (447):126.
55 Mayer RE. 1993. Illustrations that instruct. In: Glaser R, editor. Advances in Instructional Psychology. Hillsdale (NJ): Lawrence Erlbaum Associates. p. 254 284. Mercury in the Environment [Internet]. [updated 2009 Feb 19]. U.S. Geological Survey; [cited 2010 Mar 17]. Available from http://www.usgs.gov/themes/factsheet/146 00/ Milius S. 2006. Birds beware. Science News. 170(20):309 310. Millsap BA, Allen GT. 2006. Effects of falconry harvest on wild raptor populations in the United States: T heoretical considerations and management recommendations. Wildlife Society Bulletin. 34(5):1392 1400. Mitchell R. 1927. William Hunter's Anatomy of the Human Gravid Uterus. Can. Med. Assoc. J. 17(11): 1379 1383. Mooney J. 1995. Myths of the Cherokee. Mi neo la (NY): Dover Publications. Movalli P, Duke G, Osborn D. 2008. Introduction to monitoring for and with raptors. Ambio. 37(6):395 396. National Eagle Repository [Internet]. [cited 19 March 2010]. U.S. Fish and Wildlife Service Office of Law Enforcemen t. Available from: http://www.fws.gov/mountain prairie/law/eagle/ Paine RT. 1966. Food web complexity and species diversity. The American Naturalist. 100(910):65 75. Pavio A, Csapo K. 1969. Concrete image and verbal memory codes. Journal of Experimental Psychology. 80:279 285. Payne R. 1971. Acoustic location of prey by Barn Owls ( Tyto alba ). J. Exp. Biol. 54: 535 573. Pokras MA, Kneeland MR. 2009. Understanding lead uptake and effects across species lines: A conservation medicine approach. In: Watson R T, Fuller M, Pokras M, Hunt WG, editors. Ingestion of Lead from Spent Ammunition: Implications for Wildlife and Humans. The Peregrine Fund, Boise, Idaho, USA. Postelli K. 2000. Raptors and Roads. Road RIPorter [Internet]. [cited 2010 March 17]; 5(2). Avai lable from: http://www.wildlandscpr.org/node/257 Prelle S, Solomon J. 1996. Young people's "General Approach" to environmental issues in England and Germany. Compare. 26(1):91 103. Proby KH. 1974. Aud ubon in Florida. Coral Gables (FL): University of Miami Press.
56 Prugh LR, Stoner CJ, Epps CW. Bean WT, Ripple WJ, Laliberte AS, Brashares JS. 2009. The rise of the mesopredator. Bioscience. 59(9):779 791. Redig PT, Smith DR, Cruz Martinez L. 2009. Potent ial sources of lead exposure for Bald Eagles: A retrospective study. In: Watson RT, Fuller M, Pokras M, Hunt WG, editors. Ingestion of Lead from Spent Ammunition: Implications for Wildlife and Humans. The Peregrine Fund, Boise, Idaho, USA. Richardson CT Miller CK. 1997. Recommendations for protecting raptors from human disturbance: A review. Wildlife Society Bulletin. 25(3):634 638. Ripple WJ, Beschta RL. 2003. Wolf reintroduction, predation, and cottonwood recovery in Yellowstone National Park. Forest E cology and Management. 184(1 3):299 313. Ritchie EG, Johnson CN. 2009. Predator interactions, mesopredator release and biodiversity conservation. Ecology Letters. 12(9):982 998. Sala E. 2008 Top predators provide insurance against climate change. TRENDS in Ecology and Evolution. 21(9):479 480. Schmitz OJ, Beckerman AP, O'Brien KM. 1997. Behaviorally mediated trophic cascades: effects of predation risk on food web interactions. Ecology. 78(5):1388 1399. Sergio F, Newton I, Marchesi L. 2005. Top predato rs and biodiversity. Nature. 436:192. Shudes K. 2008. Florida Fish and Wildlife Conservation Commission comments on FPL's wind proposal, St. Lucie County [Internet]. [cited 2010 March 17]. Available from: http://www.windaction.org/documents/15891 Smallwood KS, Karas B. 2009. Avian and bat fatality rates of old generation and repowered wind turbines in California. Journal of Wildlife Management. 73(7):1062 1071. Snyder AW, Miller WH. 1978. Telepho to lens system of falconiform eyes. Nature. 275:127 129. Snyder N, Snyder H. 2006. Raptors of North America: Natural History and Conservation. St Paul (MN): Voyageur Press. Stoner D. 1925. The toll of the automobile. Science. 61(1568):56 57. Sutton, GM 1927. Mortality among Screech Owls of Pennsylvania. Auk. 44:563 564.
57 Switzer F. 1977. Saskatchewan power's experience. Blue Jay. 35:259 260. Vesalius A 1543 De Humani Corporis Fabrica Venice : Senensem and Germanum Wallach AD, Murray BR, O'Neill AJ. 2009. Can threatened species survive where the top predator is absent? Biological Conservation. 142(1):43 52. Walls GL. 1942. The Vertebrate Eye. Bloomfield Hills (MI): Cranbrook Institute of Science. Ward AB, Weigl PD, Conroy RM. 2002. Functional m orphology of raptor hindlimbs: Implications for resource partitioning. The Auk. 119(4):1052 1063. Warren L. 2005. Winged Silence. National Geographic. 207(2):70 85. Wendell MD, Sleeman JM, Kratz G. 2002. Retrospective study of morbidity and mortality of r aptors admitted to Colorado State University Veterinary Teaching Hospital during 1995 to 1998. Journal of Wildlife Diseases. 38(1):101 106. Wheye D, Kennedy D. 2008. Humans, Nature, and Birds: Science Art from Cave Walls to Computer Screens. New Haven (CT ): Yale University Press. Wiedensaul S. 1996. Raptors: The Birds of Prey. New York (NY): Lyons & Burford. Ydenberg RC, Butler RW, Lank DB, Smith DB, Ireland J. 2004. Western sandpipers have altered migration tactics as peregrine falcon populations have r ecovered. Proceedings of the Royal Society B: Biological Sciences. 271:1263 1269.
58 Glossary Human wildlife conflict An interaction or relationship in which individuals or a group of wildlife or humans have an adverse impact upon the other. Anatomical Realism A school of medical scientific illustration whose strictly observational anatomical illustrations overtly dismissed the stylistically classical artistic elements of the field's earlier practitioners, whose adherents advocated th e educational merit of the unadulterated anatomical image. Apex predator An organism residing at the top of the food chain, having no natural predators of its own. Trophic cascade A top down ecological model in which predators limit the population numb ers of their prey, consequently releasing some individuals lower in the food chain from predation. Mesopredator release A term used to describe the phenomenon in which intermediate predators thrive in the absence of top, or apex predators. Bioaccumulati on Ecological and biological event in which harmful chemicals are amassed and stored in high concentrations in long lived and top predator organisms. Retrice A tail feather of a bird of prey, of which there are between 10 and 12.