Wyniki wyszukiwania

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Bats of Saba, Netherlands Antilles: a zoogeographic perspective

100%

Genoways H. H., Larsen P. A., Pedersen S. C., Huebschman J. J.

Acta Chiropterologica

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2007

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tom 09

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nr 1

Data presented herein provide records of four species of bats new to the fauna of the Antillean island of Saba — Monophyllus plethodon, Ardops nichollsi, Tadarida brasiliensis, and Molossus molossus. Together with three species previously recorded from the island – Brachyphylla cavernarum, Artibeus jamaicensis, and Natalus stramineus – the chiropteran fauna of the island is documented to be composed of seven species. Our analysis of species/area relationships for West Indian bats provides a slope value of z = 0.177 and R2 = 0.76; therefore, the bat fauna of the West Indies has the flattest slope for this relationship of any West Indian group. This relationship is best explained by a propensity for over water dispersal by West Indian bats. We propose to unite the chiropteran faunas of the islands of Anguilla, Antigua, Barbuda, Nevis, Saba, St. Barthélemy, St. Eustatius, St. Kitts, and St. Martin by recognizing them as the Northern Antillean Faunal Area. Given the small size of Saba (12 km2) and the even smaller effective habitat for non-molossid bats (4 km2), conservation concerns are expressed for the future of the fauna and some recommendations are made for its preservation.

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Bats of Nevis, northern Lesser Antilles

88%

Pedersen S. C., Genoways H. H., Morton M. N., Johnson J. W., Courts S. E.

Acta Chiropterologica

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2003

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tom 05

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nr 2

Only one species of bat, Molossus molossus, previously has been documented as occurring on the northern Lesser Antillean island of Nevis. Field research and reviews of existing museum collections have provided documentation based on voucher specimens for an additional seven species occurring on the island — Noctilio leporinus, Brachyphylla cavernarum, Monophyllus plethodon, Ardops nichollsi, Artibeus jamaicensis, Natalus stramineus, and Tadarida brasiliensis. The biological diversity of the chiropteran fauna on Nevis is similar to that found on other islands in the northern Lesser Antilles. Ecologically, this is a simple chiropteran fauna, including one piscivore (N. leporinus), one omnivore (B. cavernarum), one pollenivore/nectivore (M. plethodon), two frugivores (A. nichollsi, A. jamaicensis), and three insectivorous species (N. stramineus, T. brasiliensis, M. molossus). Species-area and species-elevation analyses for the chiropteran fauna of the Greater and Lesser Antillean islands gave r 2 values of 0.74 and 0.33, respectively. In the species-area analysis the bat fauna of Nevis falls above the regression line and in the species-elevation analysis it falls almost on the line. The chiropteran fauna of Nevis lies outside the Lesser Antillean Faunal Core and would be best characterized as a generalized Lesser Antillean fauna that appears to be characteristic of the northern Lesser Antilles.

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Mist netting bias, species accumulation curves, and the rediscovery of two bats on Montserrat (Lesser Antilles)

76%

Larsen R. J., Boegler K. A., Genoways H. H., Masefield W. P., Kirsch R. A., Pedersen S. C.

Acta Chiropterologica

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2007

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tom 09

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nr 2

Mist nets are commonly used to survey bat populations and to estimate bat biodiversity, but several studies have found that mist net capture data and methods are biased due to a number of factors, including size and placement of nets, and the frequency at which investigators check their nets. Despite the wealth of literature and anecdotal reports, few investigators have quantified the interactions of bats with mist nets directly. We employed night vision camcorders to monitor bat behavior when bats encountered a mist net and then utilized these data to reevaluate years of survey data collected on Montserrat, Lesser Antilles. We recorded 2,523 bat passes during 43.3 hours of videotaping in July 2005 and June 2006. Observations conducted on successive nights provide evidence of avoidance-learning behavior in bats. When a mist net was present, 5.4% of bats in the airspace came into contact with the net giving an overall capture rate of 3.2% (range 0–10.3%). Mist nets are not accurately sampling bats that utilize flyways on Montserrat and such fieldwork thereby generates potentially misleading data. Biodiversity assessments and conservation guidelines based on short-term mist net surveys alone are not sufficient or reliable in regards to bats. A pragmatic solution to reduce mist net bias is to repeatedly sample a target region, utilize a variety of netting sites, use variable net sets, and carefully analyze species accumulation curves.

Ograniczanie wyników

3 Acta Chiropterologica

3 Genoways H. H.

3 Pedersen S. C.

1 Boegler K. A.

1 Courts S. E.

1 Huebschman J. J.

1 Johnson J. W.

1 Kirsch R. A.

1 Larsen P. A.

1 Larsen R. J.

1 Masefield W. P.

1 Morton M. N.

2 2007

1 2003

Bats of Saba, Netherlands Antilles: a zoogeographic perspective

Bats of Nevis, northern Lesser Antilles

Mist netting bias, species accumulation curves, and the rediscovery of two bats on Montserrat (Lesser Antilles)