|
||||||||||
|
Dillon, A. | |
Ocelot density and home range in Belize, central America: Camera-trapping and radio telemetry | |
2005 Full Book | |
Historically, ocelots (_Leopardus pardalis_) were hunted in large numbers for their fur, causing declines in population abundance across their range. In recent decades protection measures (e.g. CITES) and decreased public demand for ocelot fur resulted in declines in hunting pressure. Do to their elusive nature there is little known about ocelot population size, structure or general ecology. This lack of information hampers our ability to provide protection for this endangered species. Remote cameras were deployed in 7 grids across the landscape to estimate the density of ocelots in 2 habitat types; the broadleaf rainforest and pine forest of western Belize. Camera trapping combined with mark-recapture statistics resulted in densities of 18.91 . 20.75 ocelots per 100 km2 in the rainforest and 2.31 . 3.81 ocelots per 100 km2 in the pine forest habitat. This study examined the issues of camera spacing and animals with zero distance moved and their effect on density estimation. Increased camera spacing resulted in larger buffer sizes (increasing the effective trap area) and decreased density estimates. Inclusion of zero distance animals decreased buffer sizes and increased density estimates. Regardless of these effects, ocelot density was higher in the broadleaf rainforest than the pine forest. The ocelot density estimates in Belizean forests were lower than those in other portions of their range. The camera trapping technique demonstrated ocelots to be mostly active at night, with peaks of activity after sunset and before sunrise, and to travel low-use roads in the wet season and high-use roads in the dry season. Radio telemetry was used in this study to estimate the home range size and density of ocelots in the broadleaf rainforest of western Belize. Six collared ocelots (3 male, 3 female) were collared and tracked from September 2003 . August 2004. Male ocelots had an average home range size of 33.01 km2 (95% fixed kernel) and 29.00 km2 (100% MCP), and female ocelots had an average home range size of 21.05 km2 (95% fixed kernel) and 29.58 km2 (100% MCP). Most ocelots had larger home ranges in the dry season than the wet season. Ocelots showed a large amount of same sex home range overlap; with male-male overlap averaging 25% (100% MCP) and female-female overlap averaging 16% (100% MCP). Ocelot density determined using radio telemetry was 7.79 . 10.91 ocelots per 100 km2. The radio telemetry ocelot densities were lower and their home ranges larger in the Belizean broadleaf rainforests than those in other portions of their range. The camera trapping and radio telemetry techniques were compared against one another and combined in order to test which technique may be more successful in studying certain aspects of feline behavior. Activity budgets and density estimates determined from camera trapping were superior to radio telemetry, whereas camera trapping home ranges showed higher variation and lower resolution than radio telemetry. However, home range estimates determined from camera trapping captured long distance movements, a larger percent of territory overlap, and displayed potential for estimating an animal.s core use area. When radio telemetry data were used to create a buffer around camera traps based on the average radius of an ocelots. home range size, the resulting density estimates were smaller than those determined using the current camera trapping methodology. This study provided much needed baseline information on ocelot abundance, home range size, activity patterns, and trail use. While sample sizes were small, this study had the largest number of ocelots captured in Central America to date. Although camera trapping is already a useful tool in felid research, this study highlights the importance of further standardization of the camera trapping methodology, increasing its potential for monitoring and conservation across habitats and study sites. |
|
PDF files are only accessible to Friends of the Cat Group. Joining Friends of the Cat Group gives you unlimited access and downloads in the Cat SG Library for one year, and allows you to receive our newsletter Cat News (2 regular issues per year plus special issues). More information how to join here |
(c) IUCN/SSC Cat Specialist Group ( IUCN - The World Conservation Union) |