University of Central Florida Undergraduate Research Journal - Daisy Miller: A Study of Patriarchal Perception
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Anodorhynchus hyacinthinus, also known as the Hyacinth Macaw or the Blue Macaw, is the largest of the parrots. With an average weight of 1.36 kilograms, these parrots have a wingspan of about 1.22 meters and a length of up to 99.06 centimeters (Hagen 2004). Covered in cobalt blue feathers and possessing distinctive yellow markings around their eyes and at the base of their mandible, A. hyacinthinus looks to be always smiling.

This unique species of macaw, native to Central and South America, prefers woodland and savannah habitats and is commonly found in the Pantanal and Cerrados regions of Brazil (Schneider 2006). A. hyacinthinus are naturally destructive, and are known for using their beaks to manipulate small stones, thin branches, or bark to sharpen or clean their beaks. These birds may exhibit behaviors such as preening (using their beak and tongue to groom themselves or other macaws), vigilance activity (a pair taking turns patrolling the territorial area), wide ranges of vocalization, and fruit manipulation (holding fruit with one foot while using their beaks or tools to break apart or open mesocarp) (Lafeber Pet Trade; Schneider 2006). They are omnivores, though their diets consist mainly of palm fruit and nuts (De Paula 2017). In some cases, this species uses tools to open and remove the mesocarp of palm fruit (Schneider 2006). This species’ protein intake derives from the larvae inside nuts and fruits that have fallen or dropped to the forest floor. This macaw species also feeds on termites found in the decaying wood when building their nests (De Paula 2017).

A. hyacinthinus populations were once abundant in the Pantanal because the area is rich in manduvis trees, which are used for nesting (Pizo 2008). Unfortunately, habitat destruction, illegal bird trading, and the slow process of development and maturation in nestlings has greatly affected the species’ numbers. As a result, this species is now considered “Vulnerable,” with only an estimated 4,300 mature individuals left in the wild (Kuniy 2006, IUCN 2016). Copulation occurs year-round, but nesting occurs from November to April in South America (Hagen 2004). The female will lay one to two eggs per clutch and incubate them for 25 to 28 days, in which time the male will forage and feed the female. A. hyacinthus eggs hatch asynchronously, therefore, the mother will only bear the first hatchling (keeping the second as insurance), which will fledge in 13 weeks and stay with her for about 18 months (Kuniy 2006, Schneider 2006). Once they are able to care for themselves, juvenile A. hyacinthinus may join another flock of un-mated young adults. However, it is not uncommon to find bigger flocks of 12 to 20 individuals consisting of pairs and family trios (Schneider 2006, These birds reach sexual maturity between 6 and 10 years old. While A. hyacinthinus prefer to stay in flocks, they are socially and sexually monogamous, staying and reproducing with the same partner throughout their lifetime (Caparroz 2011).

The subjects of this study include a pair: Zack and Stitch. Zack and Stitch were both born in 1996 in different areas of the United States. Zack was transferred to the Central Florida Zoo and Botanical Gardens from a private sector in Dallas, Texas when he was six months old. Sometime later, Zack was paired with another Hyacinth Macaw as a breeding companion. The second subject, Stitch, and her mate at the time, were transferred from a private sector (also in Dallas) to Disney’s Animal Kingdom and then to the Central Florida Zoo and Botanical Gardens in 2009. Stitch and her mate were kept off-exhibit for breeding purposes. Stitch’s and Zack’s mates were later transferred to Palm Beach due to new breeding recommendations, and Stitch was subsequently paired with Zack. Originally, zookeepers had believed the pair consisted of two males from information provided by the prior owners of the A. hyacinthinus. However, recent genetic tests revealed that one of the macaws, Stitch, appears to be female.  Zack and Stitch were kept in an enclosed perching area similar to their current “Night Enclosure” until August of 2018, when the zoo built the Hyacinth Macaw “Display Enclosure”. Stitch is distinguished from Zack by a band on his left foot. Moreover, they display a noticeable physical difference; Zack is more distinctively yellow around his mandible and eyes than Stitch (Figure 1).

Figure 1. Zack (left) and Stitch (right)

Zack and Stitch are brought out to their “Display Enclosure” around 9:30 AM. This enclosure consists of eight posts connected by various branches of differing levels, lengths and extending branches (Figure 2). The post directly in front of the zookeeper’s entrance to the enclosure was labeled as Post 1, while the rest of the posts were numbered in a clockwise manner from the view of the boardwalk. There is no connecting branch between Post 3 and Post 4 to allow the zookeepers to place a Scarlet Macaw in the enclosure with the Hyacinth Macaws without risk of altercations. Three pieces of mesh fabric have been placed over the enclosure to provide shade, and two fans on the left and right corners on the outside of the habitat provide cool air. Additionally, three sprinklers placed around the enclosure hose down posts 1, 2, 3 and 6 (and all the branches in between) so the pair may cool off and find solace from the extreme heat. Two water bowls have been placed on Post 1 and Post 4. At times, zookeepers attached palm leaves or enrichment toys to the branches and posts of the enclosure.

Figure 2. A. hyacinthinus display enclosure

In response to the loss of their original mating partners, this study aims to determine if the new pair is performing courting and mating behaviors. According to Larissa Schneider (Schneider 2006), copulation of A. hyacinthinus occurs in four steps. The first of these steps, allopreening, is characterized by a pair perching side by side, ruffling their feathers and grooming each other’s feathers using their beak and tongue. The next step is cloacal allopreening, in which a pair perches side by side and the head of one individual is directed to the other’s cloaca, and vise versa; this position is followed by allopreening. Following this step is the back-to-back copulation position, in which, perched back-to-back, a pair leans their heads forward and raise their tails; specialized vocalization may begin as cloacas touch. The final step, copulation, is characterized by a pair with their heads down, tails up, tongues moving up and down, and cloacas connected. At this point, vocalization reaches a high intensity. This final step is the consummation of copulation.

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