Density and habitat preference of Ocelots (Leopardus pardalis

March 26, 2018 | Author: Anonymous | Category: Science, Biology, Ecology
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Density and habitat preference of Ocelots (Leopardus pardalis: Felidae) in a fragmented environment in the Colombian Caribbean Ocelots (Leopardus pardalis) are the largest among the small neotropical cats, they are generally solitary nocturnal and crepuscular, with occasional diurnal activity, they feed with a variety of vertebrates, especially small mammals (Emmons 1987, Ludlow & Sunquist 1987, Murray & Gardner 1997, Trolle & Kery 2003). They weigh between 10 and 15 kg, with males being heavier than females (Murray & Gardner 1997). Length of the tail is between 70 - 100 cm and the tail from 25 to 45 cm, resulting in a total length of 95 - 140 cm (Murray & Gardner 1997). Ocelots can be found from the United States to Argentina and Uruguay in a great variety of habitats through their wide distribution (Ludlow & Sunquist 1987, Emmons & Feer 1997). However, they are not considered as generalists because they show high association with dense cover, associated to higher diversity and density of small mammals (Konecny 1989, Dillon 2005). The spotted pattern in their skins is variable; each individual shows a unique pattern in their coat, allowing the potential identification of individuals as has been suggested by Karanth et al. (2004) in their surveys with tigers. In the Neotropics one of the most threatened ecosystems is the Tropical Dry Forest which, because of its fertile soils, has constituted a development spot for human settlements and object of an intense transformation (Instituto Alexander von Humboldt, 1998). In Colombia the Topical dry Forest is considered among the three most degraded, fragmented and less known. Some estimates point that between dry and subhumid forests in the country only exists about 1.5% of its original coverage, which corresponded to 80.000 km2. The National Parks System of Colombia covers about 10 million ha, of these only 41.100 ha, that is to say 0.4%, include areas involving partially dry ecosystems. In this information are not considered beach, mangrove and marshes ecosystems (Instituto Alexander von Humboldt, 1998). In Colombia, most of the remnants of dry forest are localized in areas of intense cattle ranching and farming uses, as the cases of Caribe and inter-andean valley regions (Cauca & Magdalena), in where is concentrated most of the cattle and farming production of the country. The spatial scale response of the species to different land uses and types of cover, are strongly linked to ecological attributes of the community, as species richness, local diversity, dispersion processes and intensity of habitat use. It is essential to consider these relationships to understand the ecosystem dynamics (Lyra-Jorge et al. 2009). The species Leopardus pardalis is considered sensitive to habitat loss (Di Bitetti et al. 2006), however recent studies have demonstrated that the agricultural landscape as well as other human altered matrices, are not necessarily a barrier (Lyra-Jorge et al. 2009). Even though the remnant habitat plays an important role for these sensitive species, there are results showing that the border density could prevail over the amount of habitat remnants favoring generalist species Lyra-Jorge et al. 2009). It is important to note however that the fragmentation effect as such hasn’t been quantified by species, so that there is not a minimum size for habitat patch, shape or other metrics of the landscape associated to use or preference of habitat by the ocelots (Jackson et al. 2005).

Knowing the population status, preferences regarding habitat and availability of the latter, are important steps to fill the gaps of information, above all of poorly explored areas, since these characteristics can be variable throughout the distribution of the species and trough time. Also the cover types and habitat configuration must be considered regarding issues such as management and conservation, especially when natural habitats are highly fragmented or degraded. It is important to take into account also with carnivores that they are generally the top predators in a community and because of that responsible of important ecological processes and community regulation. In the case of the Colombian Caribbean the most common landscape is a compound between patches of native vegetation immersed in a farm matrix (for cattle and agriculture). Hopefully in the cases wherein the matrix has a high amount of resources fulfills the role of habitat for certain species and is not used only as corridors connecting habitat patches (e.g. private reserves as in the case of Sanguaré). Generally there is an absence of ecological studies with ocelots in the Colombian Caribbean and in dry ecosystems both in Colombia and other countries. It is important therefore to make an assessment of the way in which the native fauna uses habitat remnants, especially those created or altered by humans, and in this case in a region as altered as the Colombian Caribbean, since they are relevant aspects to propose actions for conservation. General Objective To obtain information on ecological aspects as density and habitat preferences of the ocelot (Leopardus pardalis) present in a fragmented area in the north of Colombia Specific Objectives 

To estimate the density of the ocelot population within the Sanguaré Reserve and nearby areas.



To assess habitat preference of the ocelot in a tropical dry forest in the Sanguaré Reserve and close by areas.



To determine whether cattle ranching, common in the area, is a threat to the native ocelots.



To assess how habitat destruction and fragmentation affect the ocelot populations in the region.

Methodology The camera and track trap methodologies are used generally with species difficult to study in the field because of their stealth behavior, nocturnal activity, large area of action and avoiding humans. Track traps are a useful tool to verify the presence of a species, in particular when there is not necessary to obtain individual identification; while the camera traps are especially efficient with animals which allow an individual identification in a

natural way. The individuals of ocelot are relatively easy to distinguish because of its unique spot patterns, making camera traps ideal since it allows using the statistic model of capture-recapture to assess ecological aspects as density and in combination with the track traps the habitat use or preference. To estimate the ocelot density, there will be located 20 camera-traps in 10 sampling stations covering the area of the reserve and some gallery forests nearby, favoring places where there has been evidence of the presence of the animals. The maximum distance between them will be of 1km and with a maximum height of 50 cm above the ground. This in order to increase the detection probabilities, for subsequent identification of the individuals. The conditions about area and sampling time will be considered corresponding to a closed population so that Lincoln-Petersen estimate will be used (O´Connell et al. 2011); for relative abundance, the efective area will be estimated with a circular “buffer” surrounding each camera station, calculated with the movement of all the individuals found in two or more differents locations during the sampling (Karanth & Nichols 1998). Finally the density will be estimated dividing the abundance estimation by the effective area sampling. Regarding habitat preference, there will be a total of 55 track traps based on the percentage of area (of total sampling area) of each one of the five types of available coverage in the area (Mangrove, close to natural lagoons or areas with water, secondary forest, pasturelands, paddocks), distributed randomly in each type of coverage present in the study area, with minimum distances of 500m between them. The goodness test of Chi square will be used to compare statistic differences between the numbers of tracks of the species found in the different coverage (Sánchez-Lalinde & Pérez-Torres 2008). To determine if each of the habitat type categories are used more or less with respect to the availability, the Bonferroni intervals will be used, with a p< 0.05, where pi is the proportion of tracks in the ith coverage category, n the total number of samples and k the number of simultaneous estimates (Neu et al. 1974). The sampling time will be of a year, with the cameras active continuously; and during this period there will be 6 field trips of 15 days each one for the assemblage of the track traps and data collect for habitat preference (with daily check of the track traps), also to download the photos from the cameras and changing the batteries. Expected results We expect the data will allow assessing the capacity of the reserve to maintain populations of this species, to emphasize its importance and the need to implement plans to protect and expand this area. To improve the conservation efforts existing in the reserve and to implement new conservation efforts for this species in particular. We must state this area is not part of the national system of protected areas, and as such does not receive government support. With these results we must be able to make specific recommendations about the future management of similar areas and about the status of ocelot populations in the Caribbean region.

Bibliography Di Bitetti, M. S., A. Paviolo & C. De Angelo (2006). "Density, habitat use and activity patterns of ocelots (Leopardus pardalis) in the Atlantic Forest of Misiones, Argentina." Journal of Zoology 0(0) Dillon, A. (2005). Ocelot Density And Home Range In Belize, Central America: CameraTrapping And Radio Telemetry. MASTER OF SCIENCE, Virginia Polytechnic Institute and State University Emmons, L. H. (1987). "Feeding ecology of felids in a neotropical rainforest." Behav Ecol Sociobiol 20: 271 - 283. Emmons, L. H. & F. Feer (1997). Neotropical Rainforest Mammals: A Field Guide. Chicago, Illinois, University of Chicago Press. Instituto Alexander von Humboldt, Programa de Inventario de la Biodiversidad, Grupo de Exploraciones y Monitoreo Ambiental GEMA (1998). Bosque seco tropical (Bs-T) en Colombia: 1-24. Jackson, V. L., L. L. Laack & E. G. Zimmerman (2005). "Landscape Metrics Associated With Habitat Use By Ocelots In South Texas." Journal Of Wildlife Management. 69(2): 733-738. Karanth, K. U., R. S. Chundawat, J. D. Nichols & N. S. Kumar (2004). "Estimation of tiger densities in the tropical dry forests of Panna, Central India, using photographic capture–recapture sampling." Animal Conservation 7(3): 285-290. Konecny, M. J. (1989). "Movements & food habits of sympatric carnivores in Belize." Advances in Neotropical Mammalogy: 243-264. Lyra-Jorge, M. C., M. C. Ribeiro, G. Ciocheti, L. R. Tambosi & V. R. Pivello (2009). Influence of multi-scale landscape structure on the occurrence of carnivorous mammals in a human-modified savanna, Brazil." European Journal of Wildlife Research 56(3): 359-368. Ludlow, E. & M. E. Sunquist (1987). "Ecology and behavior of ocelots in Venezuela." National Geographic Research 34(4): 447-461. Neu, C. W., C. R. Byers & J. M. Peek (1974). "A Technique for Analysis of UtilizationAvailability Data." The Journal of Wildlife Management 38(3): 541-545. Murray, R. L. & G. L. Gardner (1997). Leopardus pardalis. Mammalian Species: 548:541–510. O´Connell, A. F., J. D. Nichols & K. U. Karanth (2011). Camera traps in animal ecolgy. Methods and analyses, Springer. Sánchez-Lalinde, C. & J. Pérez-Torres (2008). "Uso De Hábitat De Carnívoros Simpátricos En Una Zona De Bosque Seco Tropical De Colombia." Mastozoología Neotropical 15(1): 67-74. Silver, S. (2004). Estimando la Abundancia de Jaguares Mediante Trampas-Cámara. W. C. Society. Trolle, M. & M. Kery (2003). "Estimation Of Ocelot Density In The Pantanal Using Capture-Recapture Analysis Of Camera-Trapping Data." Journal of Mammalogy 84(2): 607-614.

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