An Analysis of Macaw Conservation Strategies. at the Tambopata Research Center

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1 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

2 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

3 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 cm in length, to the largest, the Scarlet Macaw (Ara Macao), of 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 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

4 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 more drawn to clay with higher sodium The Collpa Colorado clay lick near the TRC, where the macaws congregate to eat the sodium-rich clay. 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

5 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 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

6 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

7 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. The research done at this frequently visited clay lick has led to newfound information for over 15 different species of macaws. In addition, several different macaw breeding projects have been implemented in order to bring up the dwindling population numbers. The new focus for the project under Brightsmith is aimed at providing opportunities for satellite projects in other South American countries to spread the conservation efforts of the TMP to other areas of threatened macaw habitat. Some of the breeding Two of the scarlet macaw "Chicos" greet an eager TRC visitor. 7

8 strategies that the TRC has inaugurated include various breeding and rearing strategies to introduce increase numbers of macaws into the wild, as well as the construction of artificial nesting sites to promote natural breeding. In 1991, Nycander led a project in which 30 macaws were hand-raised and released at TRC; these chicos, as the TMP team knows them now, still make frequent visits to the TRC. The artificial nesting strategies range from cutting the tops of palm trees in order to promote natural decay for cavity (nesting) formation, to altered PVC pipes being hung from trees. The effectiveness of these different nesting and breeding techniques will be the focus of this paper. Hypotheses: While the aims of the Tambopata Macaw Project are at benefiting the populations of macaws, the more hands-on strategies they have implemented have, to an extent, broken the barrier that has existed between man and macaw. From hatching to habitation, the nature of macaws of this region has been altered by the TMP s researchers, which draws in the risk of natural ecological disruption and human dependency. Such concerns have led to the two hypotheses of this project: 1. The strategies for macaw nest construction that better mimic the natural ecology of the species are more beneficial to the conservation of the species than more artificial approaches. 2. Artificial breeding is less successful than natural breeding because it interferes with the chicks ability to develop familiarity and behavioral adaptations to their natural environment, establishing a dependency on human care for their survival. 8

9 Findings: Nesting Strategies: The first successful artificial nest boxes were created at the TRC in The nest boxes were made from Ireartea palm trunks and were inhabited by wild macaws. This resulted in the scarlet macaw (Ara Macoa) being the first species to fledge young one of the nest boxes. However, these nest boxes were not sustainable, in that they rotted away in less than two nesting seasons. A new nest box made from cedar wood was tested in 1992, and proved to last longer than the palm trunk nest boxes, but still rotted away very quickly (Brightsmith, 2000). This led Eduardo Nycander to design the first PVC nest box in hopes to be both successful and durable for macaw breeding. The boxes had tropical cedar tops and bottoms to more closely mimic the natural tree nests. The results showed that out of five nesting boxes, scarlet macaws used four in the nesting season. In 1999, the nest box designs were refined, replacing the wooden tops and bottoms (which rotted away) with metal disks. That year 12 boxes were set up for scarlet macaw habitation, nine of which were used for nesting. Based on the success of these boxes, plans began for new artificial nest boxes specially designed for habitation by other species of macaw and durability in their natural habitats. (Brightsmith, 2000). In 2006, Donald Brightsmith conducted an experiment in which artificial PVC nest boxes were hung in live palm trees in order to increase the nesting sites for blue-and-yellow macaws. The nest boxes were hung in the palm swamps near the research center, where blue-and-yellow macaws naturally nested. The palms of this 9

10 area, Mauritia flexuosa, have been known to be significant nesting resources for macaws for both the abundance of fruit it produces and the cavity it forms when the palm dies. The PVC pipes were left opened at the top to mimic the naturally occurring cavities of the palms, themselves. The habitation of these artificial nest boxes was then compared to the habitation of natural nests in that area. Their results showed that blue-andyellow macaws did not use any of the artificial PVC nest boxes in the swamp and the birds were not seen entering the PVC nest boxes. Less than ten miles away, 33 blue-and-yellow macaw nests were observed in dead M. flexuosa palms. One of the wooden design nest boxes at the TRC. photo by: Marika Jaeger Brightsmith suggestes that thermal characteristics, shape, drainage, or other basic characteristics of the PVC nests were unacceptable to the blue-and-yellow macaws (Brightsmith, 2006). In the same study, another attempt to promote blue-and-yellow macaw nesting was conducted in which the tops of the M. flexuosa palms were cut off, leaving the palm to slowly rot away, more accurately mimicking the natural nesting habitat of the macaws. 12 blue-and-yellow macaws made nesting attempts in these cut palms. In one nest, the bottom of the nest collapsed, destroying the eggs that were there. In another, a chick hatched from an egg, but was depredated and did not survive. In six nests, one chick fledged and survived. Four other nests were habited 10

11 by macaw pairs, but did not fledge any chicks. While the cut palms seemed to provide a better nesting habitat for blue-and-yellow macaws than the PVC nest boxes, the palms had an average lifespan of about four years, after which time the palms would fall over. In swamps with naturally dead palms, this is also the case, but 1% of the palms in these swamps die per year, so as dead palms fall every four years, more palms die, producing new suitable nesting sites. Brightsmith concluded that in order for such a managed swamp to be successful, a 100-year rotation cycle would have to be implemented, in which palms are cut and regrown (Brightsmith 2006). Data from hundreds of blue-and-gold, red-and-green, and scarlet macaw nesting observations was collected by the TRC to compare the effectiveness of natural, PVC, and wooden nest structures. These results showed that Natural nests had a 65% success (hatching of chicks) rate, while the PVC nest boxes only had a success rate of 41%. The wooden nest boxes were not inhabited by enough macaws to draw significant conclusions (Brightsmith, 2003). Artificial Rearing Strategies: In 1994, in order to gain a better understanding of the comparative health of captive macaws and wild macaws, a health survey of parent- and hand-reared scarlet macaws was conducted in the Tambopata-Candamo Reserve Zone in Southwestern Peru. The physical examination for the birds consisted of blood samples being analyzed for diseases. The results of this examination showed that the hand-reared macaws were more susceptible to Salmonella. Those that tested positive for Salmonella were known to have visited the TRC on a frequent basis. The 11

12 birds were suggested to have contracted Salmonella in the kitchen of the lodge, where chickens have been known to have been brought on multiple occasions (Karesh, 1997). In 2005, a collaborative study was done by Donald Brightsmith et al. on the use of hand-raised scarlet macaws for reintroduction in Peru and Costa Rica. In this study, 20 younger chicks were removed from natural and artificial nests in Tambopata at age 5-15 days. Many of these chicks were from nests with 2-3 chicks, and would not have survived naturally due to malnutrition associated with preferential parenting. The chicks were taken and incubated at the TRC, after which they were hand-raised in small boxes. No effort was made to isolate these chicks from human contact. As the birds grew, little to no pre-release training for the chicks occurred. The birds were not held in cages, so releases happened naturally, as individual fledging birds flew into the forest days after initial removal from the wilderness. The birds returned to the lodge to be fed within a range of 12 hours to 3 days. Of the 20 macaws that were released, 74% survived their first year. Of that 74%, 96% survived the next year. As of March 2002, 55% of the original handreared individuals were still alive, even despite the threat of 5 known raptor species that widely predate this area. The naïve birds were assumed to have learned both feeding and survival techniques from the surrounding wild populations. The released birds showed no fear for humans, and even returned regularly to the TRC for food. At the TRC, the supplemental feeding actually promoted social interactions among the flock members. This establishment of flock cohesion helped the released 12

13 birds effectively alarm call at the sight of predators and return to the lodge for safety. Conclusions: After further research and comparative analysis of the results, the original hypothesis that the strategies for macaw nest construction that better mimic the natural ecology of the species are more beneficial to the conservation of the species than more artificial approaches has been found to have been plausible and supported. As shown by the data, macaws have been observed to prefer their natural nests over artificial nests, often times leaving artificial nests uninhabited. Historically, artificial nests made from palm trunks and decapitated Mauritia flexuosa palms have had better success in terms of macaw habitation and reproduction than the more artificial PVC and wooden nest boxes. However, even though these more natural nests were preferred (thus habited) by the macaws, they were definitely not as durable or sustainable as the more artificial PVC nest boxes. Therefore, it is arguable that if the PVC boxes were somehow made to be more favorable to the macaws, they would be more beneficial to macaw conservation, since they would be more sustainable than the natural nests. In addition, the second hypothesis that artificial breeding is less successful than natural breeding because it interferes with the chicks ability to develop familiarity and behavioral adaptations to their natural environment, establishing a dependency on human care for their survival has been refuted by further research. In actuality, artificial hand-rearing can actually allow for a higher survival rate of 13

14 total chicks from one nest, especially in cases of nests with multiple eggs, since on average only one chick would receive proper nutrition from parents, leaving the others to die of malnutrition. However, increased human contact also increases the risk of exposure to diseases like salmonella, which necessitates more controlled rearing practices. As exemplified by the chicos of the TRC, hand-reared chicks can survive to fledging age and be reintroduced into the wild. Although these hand-reared macaws do return to the lodge for an easy meal, they are able to survive in the surrounding wilderness on their own, probably learning from other wild members of their species essential survival techniques. In addition, supplemental human contact after reintroduction of the macaws can actually promote social behavior, which in tern promotes flock cohesion, mating, and protection from predation. However, one might argue that these results might be different if the area of study was not protected from poaching and pet trade, as is the case in the vast majority of nonreserve macaw habitat. Such threats urge wariness for the degree to which exposure to human contact is helpful to macaw conservation in different settings. Acknowledgments: This study would not have been possible without the Sophomore College Program, particularly the course: Conservation and Development Dilemmas in the Amazon. I would like to thank Professor Bill Durham and Professor Julia Novy- Hildesley especially for organizing this course and teaching us so much about the ecology, resilience, policies and indigenous cultures at the heart of the dilemma surrounding the Amazon. I would also like to thank Rainforest Expeditions for their 14

15 wonderful hospitality and for providing our group with a phenomenal set of informative guides. A special thanks also to John Sutherland and Karen Alderete for their great attention to detail in all aspects of this course s logistics. Additionally, I would like to thank Marika Jaeger and Robert Chun for their photographs that appear in this paper. Lastly, I would like to thank all of the students and alumni who participated in this course, whose vivacious and exploratory personalities made this experience incredible on so many levels. Works Cited Brightsmith, D. J The Tambopata Project: Annual Report AFA Watchbird 28(3): Brightsmith, D., Hilburn, J., del Campo, A., Boyd, J., Frisius, M., Frisius, R., Janik, D. and Federico Guillen The use of hand-raised Psittacines for reintroduction: a case study of scarlet macaws (Ara macao) in Peru and Costa Rica. Biological Conservation 121: Brightsmith, Donald J. "Parrot Nesting In Southeastern Peru: Seasonal Patterns And Keystone Trees." The Wilson Bulletin (2005): Web. Brightsmith, Donald, and Adriana Bravo. "Ecology and Management of Nesting Blue-and- Yellow Macaws (Ara ararauna) in Mauritia Palm Swamps." Biodiversity and Conservation (2006): Print. Brightsmith, Donald. "Macaw Reproduction and Management in Tambopata, Peru II: Nest Box Design and Use." The Parrot Society UK (2000): n. pag. Print. Brightsmith, Donald. "The Clay Licks of Tambopata and Beyond." (2002): n. pag. Print. Brightsmith, Donald. Effects of Diet, Migration, and Breeding on Clay Lick Use by Parrots in Southeastern Peru. American Federation of Aviculture, Aug Web. 15

16 Iwaniuk, Andrew, ed. "Parrots Eat Nutritious Foods despite Toxins." Pols One 7.6 (2012): n. pag. Print. Nycander, Javier. Study of Natural Nest Cavitires. Macawproject.org. Wildlife Conservation Society, Web. Oldfield, Sara. The Trade in Wildlife: Regulation for Conservation. London: Earthscan Publications, Print. Powell, G., Wright, P., Aleman, U., Guindon, C., Palmenteri, S. and R. Bjork Research Findings & Conservation Recommendations for the Great Green Macaw (Ara ambigua) in Costa Rica. Tropical Science Center. San Pedro, Costa Rica. 28 pp. Powell, Luke L., Thomas U. Powell, George V. N. Powell, and Donald J. Brightsmith. "Parrots Take It with a Grain of Salt: Available Sodium Content May Drive(Clay Lick) Selection in Southeastern Peru." Biotropica 41.3 (2009): Web. Robaldo Guedes, Neiva. "Management and Conservation of Large Macaws in the Wild. Ornitologia Neotropical (2004): Print. Sanz, V. and A. Grajal Successful reintroduction of captive-raised Yellow-shouldered Amazon Parrots on Margarita Island, Venezuela. Conservation Biology 12(2): Schutt, Adelina and Christopher Vaughn Incorporating wildlife into development: The case of the Curu wildlife refuge and farm, Costa Rica. In Integrating people and wildlife for a sustainable future. Proceedings of the first international wildlife management congress. John A. Bissonette and Paul R. Krausman. The wildlife society. Bethesda, Maryland. Snyder, N. R. F., J. W. Wiley, and C. B. Kepler The parrots of Luquillo: natural history and conservation of the Puerto Rican Parrot. Western Foundation of Vertebrate Zoology, 16