Parrots, Poachers and Payloaders: Status and Natural History of the Yellow-shouldered Amazon on Margarita Island, Venezuela

Abstract

Looking at a range map for the Yellow-shouldered Amazon (Amazona barbadensis) is equivalent to pinpointing some of the most arid regions in South America. No other large parrot is as clearly adapted to and limited by serni-desertic habitats. The species' ability to deal with drought conditions is most evident on the islands off the north coast of Venezuela: no free-standing water is available for the parrots on tiny La Blanquilla Island, and the dry season on Margarita Island can be equally harsh. Still, the birds appear to make up for this water shortage by feeding heavily on cactus stems and fruits, and on a large assortment of flowers. With their toes wrapped firmly about a bundle of cactus thorns, parrots will use their bill to pull off entire thorn rosettes from the tips of cactus stems, and then gouge out the moist flesh beneath. Many of the larger candlestick cacti bear the uneven scars of parrot bills, together with the smooth round holes left by woodpeckers seeking the same moisture. The cactus fruits themselves provide a lot of moisture, and during the fruiting season almost all the birds return to the roost with their bills and faces stained red by the sticky pulp. Cacti are common and their fruit crop abundant, so that it is undoubtedly the parrots' ability to exploit this resource that has allowed them to survive in their serni-desertic coastal habitats.

When I first started research on the Yellow-shouldered Amazon, the species' situation across much of its range in Venezuela was uncertain and in some areas potentially critical. Since then, new information from surveys by FUDENA/WCI investigator Philip Desenne suggests that there are fairly stable populations on mainland Venezuela, in the coastal states of Sucre and Falcon. Roosting flocks of up to 700 birds have been sighted in these areas, and there is no immediate threat of large scale habitat destruction. On La Blanquilla Island, on the other hand, there are probably about 200 birds left, and nests are heavily poached by both transient fishermen and personnel from the permanent Navy outpost. With predation by feral cats becoming an additional problem, this population is increasingly in need of research and protection.

But the population I know best is the one on Margarita, the largest of the Venezuelan offshore islands. The island's open, arid habitat makes it an ideal study area: the birds are easy to locate, visibility is good for behavioral observations, and the local people are very supportive of our work. Culturally and geographically, Margarita can almost be considered as two separate islands. The western Macanao peninsula, the only area where parrots are presently found, connects to the main body of the island by means of a narrow sand bar and an extensive mangrove lagoon. Massive hotel and commercial developments dominate the eastern side and make it the center of national and international tourism in Venezuela. Large scale tourism has not yet reached the drier, less hospitable peninsula, and part of our work is now aimed at ensuring a sound ecological basis for the area's inevitable future development.

Macanao is hot and dry, with unpredictable rains and temperatures in the high 80's. The landscape is dominated by seasonal stream beds that radiate down to the coastal plains from the central mountains and provide accessible trails over the entire peninsula. The rivers only run with water every three or four years, and then only for a few weeks at a time, but that is enough to carry down massive amounts of coarse white sand and gravel that sustain a thriving sand-mining industry. Sand is mixed into cement for construction sites on the eastern side of the island. Together with the traditional fishing industry, sand mining is a mainstay of the local economy, supporting both the few families that own most of the land, and a whole array of machinists, truck drivers and administrators.

 

 

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