Breeding Ecology of Uyacintu Macaws

Newsabout parrot conservation, aviculture and welfare from C([jJ/£9IrEr1dParrot~t BREEDING ECOLOGY OF UYACINTU MACAWS by Celestino Prudencio da Silva, Charles A. Munn, Renato Cintra, Katherine Renton, Mariana Valqui, Carlos Yamashita. to have endangered the macaw's adapted very successfully to life in shortages of large tree cavities for two species of food plants: the close proximity to ranch personnel, nesting. palms Acrocomia aculeataand livestock, machinery, and buildings In the Pant anal, trees with large Attalea phalerata. (Muml et al. 1987, 1989). Therefore cavities sometimes are cut to The macaw's food supply seems the only challenges to the short eliminate potential roosts for intact in the Pantanal, hunters in the term survival of this species in the vampire bats, which pose a threat to Pantanal do not shoot them for Pant anal seems to be capture for cattle. Also, many or most large meat or feathers, and the birds have the illegal bird trade and potential trees in the never-flooded, high The Hyacinth Macaw (Anodorhynchus hyacinthinus), the world's largest and most spectacular parrot, is endangered with extinction due largely to capture over the past twenty years for the insatiable international trade in live parrots (Ridgely 1981, Munn et al. 1987, 1989). Also contributing to the decline of this species, especially in the Amazonian portion of its range, has been meat and feather hunting and habitat destruction (Munn et a11987, 1989). Throughout the moist or dry forests and forest-savannah mosaics inhabited by this species, it subsists almost entirely on the endosperm from the hard nuts of only one or two local palm species (Munn et al. 1987,1989,Roth 1989). In most parts of its range, this macaw appears not to be suffering from shortages of palm nuts. Even in the southern part of its range in the alternately flooded then parched savannah-forest mosaic of Brazil's Pantanal, many extensive cattle ranches have been in place for over a hundred years, yet we report here that this land use so far seems not "psittacine ( sini sin) Belonging or allied to the parrots: parrot-like" Hyacinth Macaws in flight. New painting, 13"x 11': by Ma/co/m El/is. First donation of £ 750secures. Hyacinth Macaws mating. The front view is quite charming. of most large trees in larger and forests as well. Thus, these natural larger patches of high ground forest factors combined with the cutting of and selective cutting of trees with trees with large cavities to control large cavities in the lowerlying, vampire bats and clearing of upland forested islands of trees or forest for cattle pasture is leaving "capaois" might be eliminating many progressively fewer large trees with of the cavities large enough to cavities in which the macaws can provide nest sites for the Hyacinth nest. The destruction of the rare, Macaw in the Pantanal. large tree cavities may soon reduce Simultaneously, the cutting of trees the reproductive rate of the on these capaois reduces the population of Hyacinth Macaws on quality of these islands of forest as the ranch and on other ranches wet season refuges for many other throughout the southern part of the terrestrial vertebrates in the range of the species. Such a Pantanal. shortage of nest sites would leave a The rear view is not so elegant. performed on a 52,000ha. cattle senescent population of mated pairs ranch in the Pantanal of Brazil, here with few cavities in which to nest. At ground forests at the borders of the we report on the density and the same time, the crucial food Pant anal are destroyed when dimensions of nest sites of Hyacinth palms on the ranch appear to be ranchers replace natural forest with Macaws and present some producing adequate nut crops at artificial pastures. Over the past observations on breeding behavior present to support a substantial several decades ranchers of the species. We also present data population of macaws. progressively have cleared more on the density and fruiting Consequently, if ranchers who high ground forest to plant pastures phenology of its two key food palms, are clearing upland forest or for their herds, which cannot graze Acrocomia aculeata (knownlocally lowland pantanal tree islands would safely in the lower, natural as "bocaiuva") and Attalea phalerata leave standing all largeSterculia, grass lands during the annual (known locally as "acuri"). In Enterolobium, Vitex,Acrocomia, and December-May flood season. conclusion, we discuss the Attalea and could eliminate all Conveniently for the Hyacinth conservation of the Hyacinth Macaw capture of macaws on their Macaw, neither of its food palms and present recommendations for properties, the Hyacinth Macaw suffers when ranchers clear the high guaranteeing its survival and would survive in substantial ground forest for pasture. The recovery in the Pantanal. numbers on their ranches for many Acrocomia palm is common in high decades. If ranchers where then to ground forest, but when clearing DISCUSSION go one step further and erect this forest, ranchers leave standing On the Estancia Caiman ranch the artificial nest boxes, use protective most or all large Acrocomia and low density of large cavities suitable fencing around existing small trees approximately 5% of the other, for Hyacinth Macaw nests resulted of these four species, and to plant non palm species of large trees. The from two natural factors: 1) forest additional trees of these species, other species of food palm of the was naturally scarce and patchy in then Hyacinth Macaw populations macaw, Attalea phalerata, which is pantanal savannah; and 2) large tree not only would survive well but rare in high ground forest, but species that develop cavities were probably even would increase common in monospecific patches rare within those forest patches. substantially on these ranches. on the edge of lower, seasonally Trees large enough and also In 1984the weights obtained by flooded terrain, is not affected by naturally prone to developing the R. Cintra of the larger, surviving the deforestation of higher ground roomy cavities required by these nestling in the wild nest at the forest. huge parrots appeared to be estimated ages of 10, 19, and 30 Possibly, however, the cutting uncommon to rare in the upland days compared well with the 2 .. weights of two known-aged, parent- increase the percentage of nesting food (but see Roth 1989, who ecologicalawareness that has swept fed nestlings from a captive nest pairs in the adult population. reports seeing the species eat snails much of middle-and upper-class (Low 1991; 125g vs. 122and 130g, The use of a break-away or on one occasion, and Schubart et al. Brazil since 1987, and in 1990the 350 g vs. 320 and 358 g, and 513 vs. removable radio collar on parent 1965, who report the species enormous success in Brazil of the 570 and 598 g, respectively). The birds or fledglings would permit occasionally eating figs and the nightly, 60-minute TV drama entitled last measurement, however, study of the ranging behavior and fruits of a species of myrtac). The "Pantanal" (which regularlycut suggests that the growth rate of the habitat use of the species, which growth, fruiting, and regeneration of away to actual clips of Pantanal wild nestling may have been falling would help us to determine if food the key palms should be studied wildlife, including wild Hyacinth behind that of the captive-bred shortage or difficulties with foraging throughout the different seasons in Macaws),the future survival ofthe nestlings, but more data from wild occur during the breeding season. natural and logged upland forest, in macaw on the ranches of the and captive nestlings are required Yamashita (in review) believes that new and old upland pastures with Pantanal seems more and more before different patterns in growth the Glaucous Macaw Anodorhynchus and without some remaining large likely. The measures outlined here rates may emerge. glaucus, an extinct sibling species of trees, and in natural and modified and increased efforts to eliminate Saunders (1982) suggested that the Hyacinth Macaw formerly found pant anal grass lands and woodlands. illegal trade in live macaws should wild nestlings of White-tailed Black in the lower Uruguay and Parana Extinct megafauna (Leme 1911, guarantee the survival of this Cockatoos may have grown at Rivers near the Uruguay-Paraguay- Almeida 1945, both referenced in species in the Pantanal wellinto the significantly lower rates when very Argentina border, disappeared early RADAMBRASlL 1982) probably middle of the next century. high daytime temperatures hindered in this century because domestic swallowed the fruits of both The future of the Hyacinth foraging by the parents. Similarly, cattle ate and trampled all young Acrocomia and Attalea palms of the Macaw inthe forests ofthe Eastern the extremely high temperatures, specimens of the bird's unique, local Pantanal, digested off the swe~t, Amazonand the drier forests of high humidity, and intense isolation food palm, Butia yatai. sticky mesocarp, and passed intact northeastern Brazil may not be as of the Pantanal during the nesting Alarmingly, Brandt and through their systems or guaranteed, however, for unlike the season might hinder the foraging of Machado (1990) recently reported regurgitated intact the hard, inner Pantanal, where most people nestling-feeding Hyacinth Macaws, that scarcity of the food palms of nuts, which later germinated and currently have enough animal which would slow nestling growth. the Indigo Macaw (A. lean) of grew in the grasslands of the protein and other food, inthe This possibility should be examined northeastern Brazil (the only other Pantanal (Janzen and Martin 1981). Amazon and in northeastern Brazil more carefully. sibling species of the Hyacinth These same huge grazing and animal protein is scarce, and the Finally, the possible effects of Macaw) forced all of the 60 browsing animals probably helped Hyacinth Macawis large enough to ectoparasites on the growth rate remaining wild birds to fly great maintain the Pantanal in its open be worth shooting for meat (Munn and survival of nestlings Hyacinth distances daily to forage over 140 and semi-open condition much as et al.

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