Circadian activity patterns and temporal overlap among cracids (Aves: Cracidae) within a vegetation mosaic in the Pantanal of Rio Negro, Brazil

Vertebrates, overall, present a daily activity pattern when managing their needs, such as foraging, resting or searching for sexual partners. Most of the available information regarding the circadian rhythm in birds comes from controlled laboratory conditions, and little is known about these patterns in the wild. In this study we used camera traps to describe the daily activity patterns of three cracid species in the Pantanal of Rio Negro, Brazil. We had a sampling effort of 9,617 camera trap-days along 231 days (5,544 hours) from September 2013 to May 2014. This resulted in 4,833 independent records of cracids from a total of 7,713 individuals. Crax fasciolata was the species with the most records (nrec = 3,792) and individuals (nind = 5,781), followed by Ortalis canicollis (nrec = 934; nind = 1,758) and Aburria grayi (nrec = 107; nind = 174). None of the species was uniformly distributed throughout the day, thus evidencing a periodization of their activities. The mean vectors of the activity patterns of C. fasciolata, O. canicollis and A. grayi were, respectively, mµ = 10:36 ± 04:26 (SD), mµ = 11:42 ± 03:57 and mµ = 11:44 ± 03:47. We observed a temporal overlap between A. grayi and O. canicollis, whereas C. fasciolata significantly differed from them. Because of their large home ranges, cracids are important indicators of environmental quality, and, as frugivores, they play key roles in the ecological dynamics of forests. In this sense, and given that cracids are notably more susceptible to extinction, the knowledge on their circadian activity patterns may be useful when establishing effective management and conservation strategies.(AU)

Medium and large-sized mammals of a fragment of cerrado in the Triângulo Mineiro region, southeastern Brazil / Mamíferos de médio e grande porte de um fragmento de cerrado na região do Triângulo Mineiro, sudeste do Brasil

This work was developed to determine the species richness and composition of medium and large-sized mammals and to evaluate spatial and seasonal distribution of the more frequent of these species in a fragment of Cerrado. The fieldwork was conducted at the Gloria Experimental Farm, a property of the Federal University of Uberlândia, from August, 2008 to October, 2009. Four sample sites were investigated including three physiognomies: gallery forest, cerrado sensu stricto and semi-deciduous forest. The surveys were conducted during the day and mammals were recorded through direct (visualizations and vocalizations) and indirect (tracks, feces, bones and fur) evidences. A total of 18 species was recorded (seven Orders and fourteen families) and the majority of them was classified as medium mammals. The highest relative frequencies were registered for Procyon cancrivorus, Dasypus novemcinctus, Myrmecophaga tridactyla and Chrysocyon brachyurus. The gallery forest showed the highest species richness. However, most species roamed over several physiognomies, indicating a generalist use of habitat. There was no significant difference in the seasonal distribution of the majority of the analyzed species. M. tridactyla, C. brachyurus, Lontra longicaudis e Pecari tajacu are endangered mammal species in the State of Minas Gerais. We conclude that the study area has a representative mammalian fauna and great potential for conservation biology, as indicated by the presence of threatened species.

Este trabalho foi desenvolvido para determinar a riqueza de espécies e composição de mamíferos de médio e grande porte e avaliar a distribuição espacial e temporal das espécies mais freqüentes em um fragmento de Cerrado. O trabalho de campo foi conduzido de Agosto de 2008 a Outubro de 2009, na Fazenda Experimental Gloria, uma propriedade da Universidade Federal de Uberlândia. Quatro sítios de amostragem foram investigados, incluindo três fitofisionomias: mata de galeria, cerrado sensu stricto e floresta semi- decídua. Os registros foram realizados durante o dia e mamíferos foram registrados através evidência direts (visualizações e vocalizações) e indiretas (trilhas , fezes , ossos e pele ). Um total de 18 espécies foi registrado (sete ordens e quatorze famílias), sendo a maioria delas classificada como mamíferos de médio porte. As maiores freqüências relativas foram registradas para Procyon cancrivorus, Dasypus novemcinctus, Myrmecophaga tridactyla e Chrysocyon brachyurus. A mata de galeria a maior riqueza de espécies. No entanto, a maioria das espécies percorria várias fisionomias, indicando um uso generalista de habitat. Não houve diferença significativa na distribuição sazonal da maioria das espécies analisadas. M. tridactyla, C. brachyurus, Lontra longicaudis e Pecari tajacu são espécies ameaçadas de mamíferos no Estado de Minas Gerais. Conclui-se que a área de estudo tem uma fauna de mamíferos representativa e grande potencial para conservação biológica, como indicado pela presença de espécies ameaçadas.