Bingham A.M.,University of South Florida |
Burkett-Cadena N.D.,University of Florida |
Hassan H.K.,University of South Florida |
McClure C.J.W.,Peregrine Fund |
Unnasch T.R.,University of South Florida
American Journal of Tropical Medicine and Hygiene | Year: 2014
Studies investigating winter transmission of Eastern equine encephalitis virus (EEEV) were conducted in Hillsborough County, Florida. The virus was detected in Culiseta melanura and Anopheles quadrimaculatus in February 2012 and 2013, respectively. During the winter months, herons were the most important avian hosts for all mosquito species encountered. In collections carried out in the summer of 2011, blood meals taken from herons were still common, but less frequently encountered than in winter, with an increased frequency of mammalian- and reptile-derived meals observed in the summer. Four wading bird species (Black-crowned Night Heron [Nycticorax nycticorax], Yellow-crowned Night Heron [Nyctanassa violacea], Anhinga [Anhinga anhinga], and Great Blue Heron [Ardea herodias]) were most frequently fed upon by Cs. melanura and Culex erraticus, suggesting that these species may participate in maintaining EEEV during the winter in Florida. Copyright © 2014 by The American Society of Tropical Medicine and Hygiene.
Whytock R.C.,Ebo Forest Research Project |
Whytock R.C.,University of Stirling |
Buij R.,Wageningen University |
Virani M.Z.,Peregrine Fund |
Morgan B.J.,Institute for Conservation Research
ORYX | Year: 2016
The commercial bushmeat trade threatens numerous species in the forests of West and Central Africa. Hunters shoot and trap animals, which are transported to rural and urban markets for sale. Village-based surveys of hunter offtake and surveys of bushmeat markets have shown that mammals and reptiles are affected most, followed by birds. However, hunters also consume some animals in forest camps and these may have been overlooked in surveys that have focused on bushmeat extracted from the forest. A number of studies have used indirect methods, such as hunter diaries, to quantify this additional offtake but results can be difficult to verify. We examined discarded animal remains at 13 semi-permanent hunting camps in the Ebo Forest, Cameroon, over 272 days. Twenty-one species were identified from 49 carcasses, of which birds constituted 55%, mammals 43% and other taxa 2%. The mammals identified were typical of those recorded in previous bushmeat studies but we recorded several species of birds rarely recorded elsewhere. Offtake of bird species increased with mean body mass. We extrapolated our results to the 34 known hunting camps in the Ebo Forest and estimated that a minimum of 97 birds are hunted annually in a catchment area of c. 479 km2. We conclude that some bird species may be hunted more frequently than previous research suggests and this has important conservation implications for larger-bodied species such as raptors and hornbills. Copyright © Fauna & Flora International 2014.
Ibarra J.T.,University of British Columbia |
Ibarra J.T.,Environment Canada |
Martin K.,University of British Columbia |
Altamirano T.A.,University of Chile |
And 2 more authors.
Journal of Wildlife Management | Year: 2014
Owls occur at relatively low densities and are cryptic; thus, monitoring programs that estimate variation in detectability will improve inferences about their presence. We investigated temporal and abiotic sources of variation associated with detection probabilities of rufous-legged owls (Strix rufipes), a threatened forest specialist, and austral pygmy-owls (Glaucidium nana), a habitat generalist, in temperate forests of southern Chile. We also assessed whether detection of 1 species was related to the detection of the other species. During 2011-2013, we conducted 1,145 broadcast surveys at 101 sampling units established along an elevational gradient located inside and outside protected areas. We used a multi-season occupancy framework for modeling occupancy (ψ) and detection (p), and ranked models using an information-theoretic approach. We recorded 292 detections of rufous-legged owls and 334 detections of austral pygmy-owls. Occupancy was positively associated with elevation for rufous-legged owls but constant (i.e., did not vary with covariates) for pygmy-owls. Detectability for both owls increased with greater moonlight and decreased with environmental noise, and for pygmy-owls greater wind speed decreased detectability. The probability of detecting pygmy-owls increased nonlinearly with number of days since the start of surveys and peaked during the latest surveys of the season (23 Jan-7 Feb). Detection of both species was positively correlated with the detection of the other species. We suggest both species should be surveyed simultaneously for a minimum of 3-4 times during a season, survey stations should be located away from noise, and observers should record the moon phase and weather conditions for each survey. © 2014 The Wildlife Society. © The Wildlife Society, 2014.
Otieno P.O.,Maseno University |
Lalah J.O.,Maseno University |
Virani M.,Peregrine Fund |
Jondiko I.O.,Maseno University |
Schramm K.-W.,Helmholtz Center for Environmental Research
Bulletin of Environmental Contamination and Toxicology | Year: 2010
Forensic analysis of carbofuran residues in weathered tissue samples for evidence of Furadan exposure in vultures (Gps africanus) by HPLC gave concentration (mg/Kg dry tissue weight) ranges of bdl - 0.07(carbofuran), bdl - 0.499 (3-ketocarbofuran) and 0.013-0.147 (3-hydroxycarbofuran) in beaks, bdl-0.65 (carbofuran), 0.024-0.190 (3-ketocarbofuran) and 0.017-0.098 (3-hydroxycarbofuran) in feet, 0.179-0.219 (3-ketocarbofuran) and 0.081-0.093 (3-hydroxycarbofuran) in crop content, 0.078-0.082 (3-ketocarbofuran) and 0.091-0.101 (3-hydroxycarbofuran) in muscle of a laced carcass and 0.006-0.014 (carbofuran), 0(3-ketocarbofuran) and 0.017-0.098 (3-hydroxycarbofuran) in feet, 0.179-0.219 (3-ketocarbofuran) and 0.081-0.093 (3-hydroxycarbofuran) in crop content, 0.078-0.082 (3-ketocarbofuran) and 0.091-0.101 (3-hydroxycarbofuran) in muscle of a laced carcass and 0.006-0.014 (carbofuran), 0), 0.590-1.010 (3-ketocarbofuran) and 0.095-0.135 (3-hydroxycarbofuran) in soil sampled from a poisoning site. These compounds were confirmed by GC-MS. The results showed that HPLC combined with GC-MS is suitable for forensic analysis of carbofuran residues in bird tissue samples and that forensic investigation should include its two toxic metabolites, 3-hydroxycarbofuran and 3-ketocarbofuran. © Springer Science+Business Media, LLC 2010.
Ogada D.L.,Peregrine Fund |
Kibuthu P.M.,Raptor Working Group of Nature Kenya
Journal of Raptor Research | Year: 2012
African owls are relatively little known and studying them is difficult due to negative effects of cultural beliefs and consumptive uses of owls. Over a 5-yr period from 2004-08, we studied the breeding ecology of 13 pairs of Mackinder's Eagle-Owls (Bubo capensis mackinderi), a subspecies of the Cape Eagle-Owl (B. capensis), inhabiting a densely populated farming community in central Kenya. Mean owl density was 0.24 pairs/km2 and mean nearest neighbor distance averaged over all years was 1.9 km. Most nests (65%) were located in a cave or on a covered ledge, and mean nest site elevation was 2191 m asl. Nests were located close to farms and grasslands, but far from forests. Initiation of breeding was associated with rainfall patterns. Mean breeding success was 51% and reproductive rate was 1.36 young fledged per successful pair. Increased reproductive success was associated with breeding after the long rainy season, nesting on cliffs or covered ledges, and nesting close to grasslands and human habitation. The majority (59%) of recorded owl deaths were caused by human activities and poisoning was the most common source of mortality. Compared to other populations of Bubo spp., the birds in our study area had a high breeding density but a low reproductive output. Human-induced mortality may be negatively affecting productivity in this population. © 2012 The Raptor Research Foundation, Inc.