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Sampling approach for monitoring poaching of rare cats

Sampling approach for monitoring poaching of rare cats. Homework Biodiversity 912.315 Master of Mountain Forestry Alberto Herreras Gadea 0941303. Example 1. Photographic-capture-recapture to assess tiger population by K. Ullas et al in 2006.

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Sampling approach for monitoring poaching of rare cats

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  1. Sampling approach for monitoring poaching of rare cats Homework Biodiversity 912.315 Master of Mountain Forestry Alberto Herreras Gadea 0941303

  2. Example 1. Photographic-capture-recapture to assess tiger population by K. Ullas et al in 2006. • Wild tigers are in a precarious state. Habitat loss and intense poaching of tigers and their prey, coupled with inadequate government efforts to maintain tiger populations, have resulted in a dramatic range contraction in tiger populations. tiger now occupy 7% of their historical range, and in the past decade, the area occupied by tigers has decreased by as much as 41%, according to some estimates. • Example explains a plan to assess the tiger population in the central part of Nagarahole reserve in Karnataka State, India, from 1991 to 2000. • The method used was photographic-capture-recapture. • Area of study has an area of 644 km² which support high densities of prey (more or less 56 ungulaters/km²), therefore this area supports high density of tigers. (K. Ullas et al 2006) & (Dinerstein E. 2007).

  3. Camera traps which photographed simultaneously both flanks from a distance of 3.5m using an active infrared tripping mechanism. • Locations selected to install those cameras were selected under presence of tiger signs • Number of camera-traps-nights used for this experiment was 5725 which were able to do 74 captures (individual tigers) during nine years. • To identify each specimen was enough with stripe patterns. • The study consisted of 10 "primary periods" or seasons covering nine years of experiment where tiger population was expected to be open to gains and losses. • About 10% of tigers population in the sampled area were estimated to be unavailable for being photo-captured during each primary sampling period from year to year. • 77% of tigers were estimated to the overall annual survival rate. (K. Ullas et al 2006)

  4. The rest 23% includes mainly deaths and a smaller amount permanent emigration out of study area. • Due to a substantial recruitment the tiger numbers did not decline. • Over the nine-year period, tiger densities were at levels between 7,3 and 21,7 tigers/100 km². • Prey density in Nagarahole (~56 ungulates/km²) appears to be critical for sustaining the tiger population (K. Ullas et al 2006)

  5. Example 2. Population monitoring of snow leopards using non invasive collection of scat samples: a pilot study by Janecka J.E. et al in 2008 • Is believed that 3000 to 7500 snow leopards roam across their vast range in Central and South Asia. • The snow leopard is an opportunistic predator capable of killing prey more than three times its own weight. Therefore, it may potentially prey on most herbivores found in the same range except for fully grown yak or wild ass . • Low densities of population of snow leopard and patchy distribution as a result of natural habitat fragmentation, habitat degradation, declining prey populations, poaching and other anthropogenic threats • Janecka J.E et al decided to do not use camera trapping due to several disadvantages as long time need to develop the field work, difficulty of setting camera traps in the area of interest and also the high cost. For this reason they decide to use molecular methods incorporating non invasive sampling via the collection of scats or hair. (Janecka J.E et al 2008).

  6. Detect multiple cats in brief 2-day surveys. In Ladakh detected six individuals in a 135 km² area during a camera survey conducted 45km southeast of the study area. • Level of scat species misidentification in the field, ranging from 35% in Ladakh to 54% in south Gobi. • Many scats identified as putative snow leopard origin were found to be from red fox. • Species misidentification in the field has been previously reported in studies that incorporate genetic identification of scats. • As predator densities, diet and behavioral factors may influence the proportion of scat field-misidentification, we suggest that scat-based snow leopard surveys at a minimum incorporate genetic species identification (Janecka J.E et al 2008).

  7. Example 3. Census-diagnosis of Iberian lynx populations in Spain by Guzmán D. et al in October 2002. • Iberian lynx is an endangered species in Spain and virtually extinct in Portugal. Iberian lynx is strictly protected in Europe by Berne agreement. • This experiment developed by Guzmán D. et al try to identify all changes occurred during last 20 years on lynx population, as well as, current status of this specie on the area of interest and allowing differentiate a temporal evolution • The objective is to obtain and display a snapshot of the populations of Iberian lynx in Spain at present, identify actual and potential areas of distribution, and try to identify the factors that have affected the species in the last decade with the order to influence these factors to improve the chances of survival of last Iberian lynx. (Guzmán D. et al 2002).

  8. Frequently used methods include the work through personal surveys and interviews, background information, search for tracks and droppings, data from trapping and hunting statistics and a variety of methods based on capture-mark-recapture trapping ranging from scientific and marking of specimens for subsequent radio-up photo-identification techniques using camera traps with different attractants or placed step. • Stable populations are ongoing and reproduction observed in about 350 km ², so that the species would be relegated only 0.064% of the country (Spain), and stands at the threshold of extinction. (Guzmán D. et al 2002).

  9. References • E. Dinerstein, C. Loucks, E. Wikramanayake, J. Ginsberg, E. Sanderson, J. Seidensticker, J. Forrest, G. Bryja, A. Heydlauff, S. Klenzendorf, P. Leimgruber, J. Mills, T. G. O´Brien, M. Shrestha, R. Simons, and M. Songer (2007): The Fate of Wild Tigers. • J. E. Janecka, R. Jackson, Z. Yuquang, L. Diqiang, B. Munkhtsog, V. Buckley-Beason & W. J. Murphy (2008): Population monitoring of snow leopards using noninvasive collection of scat samples: a pilot study. • J. Rodney, H. Don O. (1996): Snow Leopard Survey and Conservation Handbook Part III. • K. Ullas Karanth, James D. Nichols, N. Samba Kumar, and James E. Hines (2006): ASSESSING TIGER POPULATION DYNAMICS USING PHOTOGRAPHIC CAPTURE-RECAPTURE SAMPLING

  10. References • Nicolás Guzmán López-Ocón J., José García Gonzalez F, Pérez de Ayala Balzola R., Concepción Iglesias Llamas M., Heredia Armada B. (2002): CENSO-DIAGNÓSTICO DE LAS POBLACIONES DE LINCE IBÉRICO Lynx pardinus EN ESPANYA • Rodríguez, A. (2004). Lince ibérico - Lynx perdinus. En: Enciclopedia Virual de los Vertebrados Españoles • http://www.snowleopardconservancy.org/text/conservation/conservation1.htm (Abril 2012) • http://www.iucnredlist.org/apps/redlist/details/15955/0 (Abril 2012)

  11. Thank you for your attention

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