Comunidades de morcegos na caatinga e brejo de altitude, no Agreste de Pernambuco

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

The fauna of Brazilian bats is composed of 166 species and 76 occur in the caatinga. In spite of the high diversity of bats in the caatinga, there are still scarce the studies with this group in this biome. Extensive gaps of knowledge related to its distribution in the caatinga with some areas without any information referring the bats. Caatinga is a typical Brazilian biome covering around 98.000 km2. Its physiognomy is quite heterogeneous with vegetation typical of arid zones and enclaves of mesic forest, known as brejo de altitude, which are composed upper than 1000m of altitude. This study aimed to identify the composition of fauna, diet and reproduction of the species of bats from one typical caatinga vegetation and other from brejo de altitude, both in the northeast of Brazil. The animals were collected monthly from February 2005 to January 2006, during six consecutive nights, totalizing 5040 hours using nets in each sampled areas. In the caatinga were registered 21 species and 587 captures and in the brejo de altitude were registered 20 species and 819 captures. The diversity and equitability (H = 2.39 and H = 1.97; 0.78 and 0.64, respectively) were greater in caatinga than in brejo de altitude In the caatinga, four species were considered abundant, six intermediary and 11 rare; in the marsh were registered two abundant, six intermediary and 12 rare. In the caatinga, the most abundant specie was Artibeus planirostris (n = 139, 23.67%) and in the marsh was Artibeus fimbriatus (n = 322, 39.3%). In both areas occurred the dominance of Phyllostomidae. It can be detached the presence of Pygoderma bilabiatum, Artibeus fimbriatus, Lasiurus egregius and Myotis rubber not registered in the literature to areas of caatinga properly stated and the presence of Lasiurus ega as the first occurrence to brejo de altitude areas. Furthermore, these species are weakly sampled in the Northeast region. The bat species catalogued can be divided in insectivorous (n = 9), frugivorous (n = 7), nectarivorous (n = 3), haematophagous and omnivorous (n = 2) and carnivorous and piscivorous (n = 1). Considering the abundance, the frugivorous were detached (n = 1044), followed by the nectarivorous (n = 174), insectivorous (n = 100), haematophagous (n = 58), omnivorous (n = 25) and carnivorous (n = 3). From fifty items eaten by the bats, 38 occurred in the samples from the caatinga and 35 from the brejo de altitude, among fruits (n = 31), pollen/nectar (n = 16), small vertebrates (n = 1), fish (n = 1) and several insects. Twenty two items were common to the two areas, while 15 occurred only in the caatinga and 13 from the brejo de altitude. In the matrix of niche, 17 cells were occupied by 25 species of bats. There was superposition between frugivorous from the canopy of high tree (Artibeus planirostris / Artibeus fimbriatus) and the frugivorous from the sub-forest (Carollia perspicillata / Pygoderma bilabiatum / Sturnira lilium). In the category of nectarivorous there was superposition between the species Glossophaga soricina / Lonchophylla mordax; in the haematophagous (Desmodus rotundus / Diphylla ecaudata) and between insectivorous of gaps (Myotis nigricans / Myotis ruber / Rhogeessa io), the other cells were filled out by isolated representatives. The biggest values of superposition of food niche were obtained in the brejo de altitude and the lowest in the caatinga, indicating a bigger competition for food resources in the marsh. Regarding the number of food items consumed, Glossophaga soricina was detached, showing the greater value in two studied areas, 18 items in the caatinga and 20 in the brejo de altitude. Lonchophylla mordax (n = 16) and Carollia perspicillata (n = 14) were detached in the caatinga; the last specie is also detached to the brejo de altitude (n = 15), followed by Artibeus fimbriatus (n = 12). Among the captured animals, 658 and 748 were male and females, respectively, in a sexual ratio of 0.88 males/females. In the brejo de altitude, 384 males and 435 females were captured, and in the caatinga, 274 males and 313 females, with a sexual ratio of 0.88 and 0.87, respectively males/females. The sexual ratio from the major of species followed the standard of 1:1, approximately, with a tendency to capture more females. Twenty species were captured in a reproductive activity, 15 occurring in the caatinga and 14 in the brejo de altitude. From 74 females captured, 383 were reproductively actives, among them, 222 pregnant ones, 139 lactants and 22 both pregnants and lactants. There did not take place differences accented for the reproductive periods between the populations of bats in two studied areas. Proportionally to the number of females captured in reproductive activity there took place a bigger number of collections of pregnant females in the dry station and of sucking ones in the rainy one. Regarding the age structure it was noticed the presence of young individuals in the rainy station, which can indicate a period of recruitment of the cubs that began to fly. The oestrum powders-childbirth took place in five sorts, Artibeus fimbriatus (n = 9), Artibeus lituratus (n = 6), Artibeus planirostris (n = 5), Carollia perspicillata (n = 1) and Glossophaga soricina (n=1). This was noted by the capture of females that were simultaneously pregnant and lactating. A female of Platyrrhinus lineatus was captured pregnant in April and re-captured in December, again pregnant. Such registers show a polyestrous.

ASSUNTO(S)

morcegos - reprodução reproduction morcego - hábitos alimentares - pernambuco ciencias biologicas mamíferos - diversidade biológica chiroptera caatinga food habit caatinga community

ACESSO AO ARTIGO

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