An Analysis of Macaw Conservation Strategies at the Tambopata
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An Analysis of Macaw Conservation Strategies at the Tambopata Research Center Brian Leahy Sophomore College 2013 October 14, 2013 Blue-and-yellow Macaws at the Collpa Colorado Abstract: Macaws are becoming increasingly threatened with endangerment and, in some cases, extinction largely due to poor reproductive rate and progressively higher levels of deforestation and exploitation. As a way to combat the dwindling populations, macaw preservation techniques have been implemented in some South and Central American locations. The Tambopata Macaw Project in the Madre de Dios region of Peru has been the leading force of this macaw conservation effort. Their efforts at supporting the proliferation of this species have included the protection and management of macaw habitat, the construction of artificial macaw nests, and the hand-rearing of macaw chicks in captivity for later reintroduction into the wild. The increasing level of human contact with the ecology of macaw species in Tambopata, Peru has raised some concerns about how beneficial artificial breeding and rearing strategies are to the overall conservation of macaws. In this paper, the negative and positive effects of artificial strategies of macaw conservation taking 1 place in the Tambopata Research Center are analyzed in order to assess whether increased human care for the macaws in this region of the Peruvian Amazon. Background: There are six total genera of macaw: Anodorhynchus, Cyanopsitta, Ara, Orthopsittaca, Primolius, and Diopsittaca, all of which are native to Central and South America, parts of Southeastern Mexico, and formerly the Caribbean. Their relatively large size, long protruding tails, and beautiful vivid-colored plumage mark these spectacular members of the Psittaciforme (parrot) family. The Neotropical genus Ara contains the highest number of species, ten, two of which have already gone extinct. Macaws stand at a high risk of extinction mostly due to both aspects of their own ecology, including high selectivity for nesting habitat and low reproductive rate, and anthropogenic influences, namely destruction of habitat by deforestation and the illegal pet trade. The intricate designs of the macaws distinguish them from the rest of their parrot family. Both their colorful feathers and distinctive facial patch are said to be as unique as a fingerprint. However, these differences are so subtle that two macaws are virtually A scarlet macaw perches itself on a bed in one of the TRC rooms. Photo by: Robert Chun 2 indistinguishable from one another. The size range for Macaws varies from the smallest species, the Red-shouldered Macaw, or Hahn’s Macaw (Diopsittaca nobilis), of 30-35 cm in length, to the largest, the Scarlet Macaw (Ara Macao), of 81-96 cm in length. More than half of a macaw’s length is attributable to its long, graduated tail, which, along with its impressive wingspan, makes it an apt, agile flyer with the ability to reach speeds up to 56 kilometers per hour. Macaws have zygodactylous feet, with two toes pointing forward and two pointing backward, which, functioning like hands, allow them to easily grasp food and bring items to their mouths, as well as sturdily perch onto and walk about tree branches. Unlike most large birds, macaws are not birds of prey, but rather generalist herbivores (Gilardi, 2012). Other than a trace amount of snails and insects, their diet consists mainly of fruits, berries, palm stems, flowers, nectar, foliage and nuts found in their rainforest environment. Their powerful angular beaks, with estimated bite strength up to about 500-700 psi, support the macaw’s diet, allowing them to break open even the toughest Brazil nut shells with ease. Their dry, scaly tongues actually contain a small bone that allows it to function almost as a tiny finger, a useful tool for licking off morsels of food into their beaks. As a way of decreasing dietary competition, macaws tend to forage on unripe fruits and tough nuts that are too difficult for most other creatures in their habitat to eat. In the lowlands of the Peruvian Amazon (the focus for this paper), many of the under-ripe fruits and nuts present in macaw diet contain toxins and other caustic materials that plants have adapted as physical and chemical defense mechanisms. The ability to digest these toxic fruits allows the macaws to exploit an 3 abundance of foods rich in nutrients, throughout both rainy and dry seasons (Gilardi, 2012). While the macaws are able to digest these substances, they can cause severe dietary issues if ingested in large quantities. As a way of neutralizing these toxins, macaws eat sodium-rich clay off of riverbanks, also known as “collpas” or “clay licks,” which neutralize these toxins; the clay particles actually bind together with the toxins, preventing absorption of the toxins, which are passed out with fecal matter (Brightsmith, 2003). While the clay from these macaws’ diets are rich in antioxidants, the macaws seem to be The Collpa Colorado clay lick near the TRC, where the macaws congregate to eat the sodium-rich clay. more drawn to clay with higher sodium content rather than higher antioxidant content (Powell et al. 2009). These findings, as well as evidence of macaws feeding on salt from salt mines, have lead to theories of sodium craving in Macaw diet. Whether it is for antioxidants or satisfaction of a salty appetite, macaws are driven to congregate at clay licks almost daily, with a strong influence on weather conditions and breeding conditions (Brightsmith, 2004). The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has listed 7 species of macaw on their Appendix II, which lists species that aren’t necessarily threatened with extinction, but have a high risk of becoming extinct unless trade is closely monitored. Appendix I, which lists species 4 that are most critically endangered and threatened with extinction, contains 11 species of macaw, 3 of which (the Blue-headed macaw, the Red-fronted macaw, and the Scarlet macaw) are endemic to the Tambopata region. One of the main drivers of the dwindling populations of macaws is their naturally low reproductive rate. Macaws are generally highly selective of their nesting habitat, preferring deep, dry nest cavities on old growth trees that only occur at abundances of about one per 12-20 hectares of rainforest habitat. This selectivity for suitable habitat makes it difficult for macaws to nest and fledge young. Even when the macaws do nest, usually only a small fraction of their eggs survive, due to predation of the eggs by jays, crows, and toucans. Even if eggs survive to hatching, the parents will often only care for and feed one or two of these eggs (usually the strongest of the fledglings), leaving the smallest to die of malnutrition. While the naturally low reproductive rate puts macaw populations at a disadvantage, the largest drivers of their endangerment are anthropogenic: namely the destruction of habitat and exploitation for the pet trade. With agricultural slash and burn, urbanization, and projects like the Southern Interoceanic Highway, Peru’s deforestation rate has increased significantly from 0.14 percent in 2005 to 0.22 percent in recent years. The Interoceanic Highway, which was completed in July 2011, cuts across the Tambopata reserve and has destroyed a great deal of ecosystem and biodiversity in this region. In addition to projects like these, selective logging in the Peruvian Amazon often targets the scarce old growth trees that macaws rely on for nesting. 5 While CITES lists the vast majority of macaw species as illegal to trade, lack of enforcement of these regulations has led to the proliferation of trade of endangered species. In Bolivia, a powerhouse in the South American bird trade, a monitoring of the parrot pet trade from August 2004 to July 2005 found that 94% of parrot individuals were believed to have been caught in the wild and several species present in the trade were listed as endangered, such as the Hyacinth Macaw, the Blue and Yellow Macaw, and the Scarlet Macaw (Hennessey and Herrera, 2007). This study, which shows the high level of illegal parrot trade in Bolivia, suggests that this is probably true for Peru and other receiving markets of the trade, such as Brazil. In the illegal smuggling of illegally traded macaws, 90% of macaws do not survive because of hazardous conditions of transportation. The going rate for a rare species of macaw can be as high as $50,000 in the illegal trade market. One estimate by the United Nationals Environment Programme priced the annual illegal contribution of the pet trade in between $5—8 billion. (Oldfield, 2002, page 13). These high prices provide large incentives for illegal traders, especially when penalties are minimal to non-existent. These threats to macaw populations led Eduardo Nycander to start the Tambopata Macaw Project in 1989, with the aims of gathering data on the ecology and natural history of macaws in order for conservation applications. The project is located on the Tambopata River at the center of a large reserve site in the Madre de Dios Region in Peru, surrounded by acres of pristine rainforest. This project led to the construction of the Tambopata Research Center in order to house the project’s research team. As Nycander began to concentrate on establishing the ecotourism 6 company Rainforest Expeditions, as a way of ensuring funding for the Tambopata Research Center, he passed on leadership of the project to Donald Brightsmith of Texas A&M University. Since his acceptance of the TMP torch, Brightsmith has taken the level of macaw research to new heights, publishing countless works on his team’s firsthand observations of macaw behavior, physiology, breeding habits, and phylogeny. The location of the Project in the Peruvian Amazonian basin is ideal for macaw research, with the largest known macaw clay lick, the “Collpa Colorado,” just down the river from the TRC’s port.