University of Central Florida Undergraduate Research Journal - Self-Injurious Behavior of a Captive <i><i><i>Coragyps atratus</i></i></i>
US tab

Self-Injurious Behavior of a Captive
Coragyps atratus

By: Jennifer Bouchenot | Mentor: Frank Logiudice

Materials, Methods, and Study Specimens

Lurch is an eleven-year-old male Coragyps atratus housed at the Central Florida Zoo. He was found as a healthy chick and brought to a rehabilitation center. Lurch imprinted onto humans during the rearing process. Imprinting is a consequence of human interaction that occurs during early development in a bird's life and is an irreversible process that affects bird behavior socially and sexually. Such imprinting can be so severe that the bird is unable to recognize a potential mate from its own species (Immelmann, 1972). Typically, imprinted birds cannot be released back to the wild, for risk of isolation from other members of its species (Slagsvold, Hansen, Johannessen, & Lifjeld, 2002). This form of imprinting enabled Lurch to be less aggressive towards keepers and have a propensity to learn basic commands.

Lurch was initially placed at Silver Springs Zoo and was used as a show bird. The show schedule ensured that he flew twice a day. At night he was kept inside an enclosed building. In 2013, the Silver Springs Zoo closed and Lurch was moved to the Central Florida Zoo in Sanford, Florida. According to his keepers, he was initially used as an "animal ambassador" in both shows and education programs. After a year at Central Florida Zoo, Lurch began feather picking. The feather picking reportedly began in 2014, during the Thanksgiving holiday, when staff visitation with the animals may have been less frequent. Shortly after he began feather picking, aviculturists made the decision to discontinue his participation in shows and programs due to the extent of his injuries. A study on Lurch completed in 2017 concluded that the self-harm was a product of contingent anthropomorphic attention (Morris, 2017). Lurch self mutilated more frequently when keepers provided attention. Topical ointments, blocking devices, and increased enrichment were used in an attempt to curtail the self-mutilation with little success. This study aims to observe other possible solutions to the self-mutilation.

Lurch's enclosure is a 2.5 meter deep by 3 meter wide by 2 meter high chain link cage. Within the enclosure, a 1 meter x 1 meter wooden mew is located in the back left of his enclosure for roosting and sleeping. The sleeping mew is necessary to prevent predatory local wildlife from reaching in through the chain linked enclosure to attack the bird. Lurch is put into his sleeping mew before 5 PM and let out into the chain link portion of the enclosure after 8 AM daily.

Within the larger enclosure, large bare oak branches are used as perches. Perch locations are changed frequently for extra stimulation. Additional enrichment is provided in the form of toys, such as plastic balls with holes hung from branches, smaller balls on the ground, and carboard boxes stuffed with paper towel rolls. A fan blows air into the enclosure from the back, which includes a 1 meter by 8 meter metal sheet for rain protection. The floor of the enclosure consists of mulch with patches of grass. A safety cage is located adjacent to the enclosure and is also made of chain link fencing. Lurch's enclosure is surrounded on three sides by other enclosures and an assortment of birds and mammals. The front of Lurch's enclosure is a grassy area and a fence separating the keeper area from the public. Groups of children and guests are sometimes escorted through the area by a keeper or educator.

A second Coragyps atratus, Jeff, was also observed for comparison. Jeff was admitted to the Audubon Center for Birds of Prey as a mature bird in September 1995 with a fractured, misaligned right femur and fractured left humerus (Scott, 2010). It was assumed that Jeff was a male bird; however, in March 2008, Jeff laid an egg. Jeff has been a display animal for the Audubon center since October 1995.

Jeff's enclosure is a 3.6 meter by 3.6 meter square. The entire back of the enclosure consists of vertical oak planks separated from one another by less than 3 centimeters. The back half of the roof is solid wood for rain protection. The front half of the roof and other three sides of the enclosure is a fine fencing with 2 centimeter by 2 centimeter mesh providing good visibility to the viewing public. A brick wall is behind Jeff's enclosure with a grassy area to the right and to the front with a pathway winding past the front area. To the left of Jeff's enclosure, two C. cheriway and one Turkey Vulture (Cathartes aura) are housed. Jeff's enclosure has a sand substrate with a small fern growing near the in-ground water basin.

Lurch is fed a small food item, typically a mouse, in the morning after he is let out of his sleeping mew and is fed a larger meal in the evening shortly before he is moved into his sleeping mew. This schedule enables the administration of the 1 milliliter of Gabapentin twice a day. Jeff is fed once in the evening and is given .08 milliliter of Cosequin on Mondays for treatment of stiff joints, as she is an older bird. Jeff was given enrichment in the form of leather rings with durable plastic balls and tennis shoes. Food was occasionally hidden inside paper towel rolls. Both Coragyps atratus ate their food quickly and frequently finished their portions of food.

The study location for Lurch was in Sanford, Florida at Central Florida Zoo and Botanical Gardens in a staff only area. Jeff was observed in Maitland, Florida from a public area at Audubon Center for Birds of Prey. The observer was positioned 2 meters from both enclosures. Initially, Lurch was observed three days a week, but this was reduced to one day a week, due to the addition of the other specimen, Jeff. Observations of Lurch and Jeff were one day a week with the observation beginning before noon and typically lasting six hours.

In Florida, Coragyps atratus are sympatric with C. cheriway. Allopreening between the two species have also been observed in the wild with both participants eliciting preening from one another (Ng & Jasperson, 1984). Halfway through the study, Lurch was placed adjacent to a female C. cheriway for three days and one morning. This female C. cheriway, named Cheriway, was admitted to the Audubon Center for Birds of Prey as an immature emaciated bird with a fractured left humerus (Scott, 2010). She stayed at the center for two years until she was transferred to Central Florida Zoo and was incorporated with their King Vulture (Sarcoramphus papa) enclosure. The S. papa were loaned to a New Orleans Zoo, and Cheriway was moved to a back area.

The two birds at Central Florida Zoo, Coragyps atratus and C. cheriway, were placed in adjacent enclosures for three full days and one morning. The adjacent enclosure was 1.5 meter by 3 meter by 3 meter fencing with 2 centimeter by 2 centimeter mesh. The only divide between them was an extension of the fencing and a closed sliding door constructed from the same fencing material. The ground was concrete, and perches consisted of bare oak branches. Other enclosures were visible, including those for Red Shoulder Hawk (Buteo lineatus), Red Tail Hawk (Buteo jamaicensis), Harris Hawk (Parabuteo unicinctus), Hyacinth Macaws (Anodorhynchus hyacinthinus), and a Serval (Leptailurus serval). Within earshot was an Amur Leopard (Panthera pardus orientalis) that would call occasionally. These enclosures were on two sides of the adjacent enclosure. The other two sides consisted of a parking lot with the keeper building and a grassy bamboo area where the observer sat. Lurch was able to see the keeper building from his new enclosure and very frequently watched the keepers enter and exit the building.

On the fourth day of proximal habitation with Cheriway the C. cheriway, keepers opened the sliding door between the two and fighting occurred within a few minutes. As a result, Lurch the Coragyps atratus was moved back to his old enclosure shortly after.

Time spent for each behavior was recorded and these data were entered into a Microsoft Excel spreadsheet on a laptop. Longer times were recorded with a Galaxy S5 stopwatch. The spreadsheet divided the observation period into five-minute increments. This procedure allowed for better organization of the recorded data and the ability to generate time sensitive charts. Observations continued as long as the weather permitted. (Both facilities discouraged observations during inclement weather.) Directional information of the enclosure location is recorded from the observer's point of view. Specific bodily locations of the subject birds were made from the bird's point of view.

Feather picking was defined as any contact of the beak to the problem area. This behavior was only observed with Lurch at the Central Florida Zoo. The problem area was the left scapular, clavicle, and coracoid, in combination with the leading edge of the left wing in the humerus area, as shown in Figure 1. Preening is defined as manipulative beak-to-feather contact on any other part of the body. Rarely was preening observed without feather picking accompanying it. Resting is defined as anytime the rump or body of the specimen was on the ground, surface, or perch. This resting behavior did not include incubation or broody behavior, which was observed in both Coragyps atratus. Keepers at both facilities are defined as any staff within view or earshot of the enclosure. Both Coragyps atratus responded more strongly with keepers they're more familiar with. Lurch was observed for 15 days for a total of 96 hours and 25 minutes, while Jeff was observed for 8 days for a total of 32 hours and 5 minutes.

In this study, statistical variance was calculated for each examined characteristic for Lurch and Jeff. Using the calculated variances in combination with the averages for that characteristic, a two tailed z-test was performed in Microsoft Excel to measure statistical significance of the observed behaviors.

Figure 1: Lurch pausing between bouts of feather picking.

Results and Discussion >>