Ecologia do Alouatta fusca em floresta de encosta e de restinga no Sul do Brasil

AUTOR(ES)
DATA DE PUBLICAÇÃO

2000

RESUMO

I compared the activities in groups of the brown howler monkey A/ouatta fusca in forests growing on hillsides and on a sand flat bordering Lago Guaíba in Porto Alegre, RS, near its southern range limit. The hillside forest is taller and has a higher species diversity of trees and only two tree species Ficus organensis and Coussapoa microcarpa (Moraceae) comprised 53% of the sand forest vegetation. During 1998 and 1999 I conducted 1448 and 1160 scan samples (483 and 386 h observation) on two howler groups, one in each forest type. The troop in sand forest fed on fewer plant species both in summer and winter, and consumed fruits, especially Moraceae, more often during summer (59% vs. 39% winter, P = 0.016). During summer the occupying group hillside fed mainly on F. organensis and Lonchocarpus sp. (46%) along with several lianas, whereas in sand forest F. organensis and C. microcarpa (66.5%) predominated. In winter howlers favored Zanthoxy/um sp. (Rutaceae) on the hillside and Diospyrus inconstans in the sand forest. Calculated activity budgets showed that during the summer the hillside group spent more time in movement (8% vs. 5%, P = 0.012) and in grooming (4% vs. 2%, P = 0.003) whereas time spent feeding in the sand forest was proportionately greater (35% vs. 27%, P = 0.001). No time budget differences existed between the two groups in winter. Home range size of the hillside group varied between 6.40 (summer) and 6.15 ha (winter) with mean day ranges of 774 ( :t136, n=10) and 394 (:t126, n=10) m, respectively. The home range size of the sand forest howlers was approximately 4.0 ha independent of season and mean day ranges varied respectively from 640 (:t77 , n=9) to 338 (:t177, n=10) m in winter and summer. In general, the howlers reduced fruit consumption (availability) and were more generalist in their feeding during winter. During winter, perhaps because of the reduction in difference in resource availability, differenc.es in time budget and food specialization diminished

ASSUNTO(S)

guariba (macaco) - porto alegre (rs) restinga - porto alegre (rs) ficus (botanica) - porto alegre (rs)

ACESSO AO ARTIGO

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