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Castañeda Gaytán, J. G., López, J. B. E., Mares, A. C., Ceballos, S. V., & Westphal, I. S. , Current status of the box turtle terrapene coahuila in the wetlands of cuatrocienegas coahuila (abstract). Unpublished paper presented at 2013 Box Turtle Conservation Workshop.
Added by: Admin (06 Jan 2014 18:24:13 UTC) |
| Resource type: Conference Paper BibTeX citation key: CastaedaGaytn2013 View all bibliographic details  |
Categories: General Keywords: Emydidae, Habitat - habitat, Nordamerika - North America, Schildkröten - turtles + tortoises, Terrapene coahuila Creators: Castañeda Gaytán, Ceballos, López, Mares, Westphal Collection: 2013 Box Turtle Conservation Workshop |
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| Abstract |
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The box turtle (Terrapene coahuila) is the flagship species of the conservation area, Cuatrocienegas, Coahuila. Its importance is that it is one of the most charismatic semi-aquatic vertebrates of the valley that are basis of numerous conservation efforts due to their association with water bodies. Thus, it is considered a potential species to assess the health of wetlands and therefore identify whether conservation practices are effective today. As part of compliance with the National Commission of Natural Protected Areas (CONANP) the Mexican government has invested resources to meet the current situation of the box turtle and then implement a simple method to maintain a constant monitoring of the populations of this seriously threatened and endangered species. From June 2010 to May 2011, we assessed an area of 30 hectares 4 or 5 days per month. In addition, we selected 143 sites distributed throughout the valley to search for live turtles or traces of turtle and evaluate their potential distribution using ecological niche models (MAXENT). For sites where live specimens were observed, data were taken as to the type of microhabitat and water (if observed within the pools). All specimens were marked with notches in the shell. The general analysis of the population describes the proportion of individuals recorded per unit area, the proportion of age classes, sex and habitat use. Additionally, radio tags were placed on the carapace of 14 male and female T. coahuila to assess the areas of activity during two different periods of the years 2011 and 2012. Preliminary results point out that the species is found in wetlands in the valley with a high degree of fragmentation. There is a high probability of box turtles occurring within an area of 1.5 km sq. (intensive sampling site). Over a larger area of slightly greater than 7 km sq, the probability of box turtles occurring drops to 51%. Within the intensive sampling site, we collected approximately 95 individuals during the first year of study with a sex ratio male: female 1:0.53. Extrapolating the abundance of individuals per unit area of search yielded an approximate abundance of 3.16 ind / ha, which is a very small population for the entire valley (potentially 461 to 2268 turtles). In most cases, turtles were observed in wetlands with a depth less than 50 cm. In the case of individuals observed on land, most were located near plants of the genus Eleocharis, Scirpus, and Distichlis (species associated with permanent water film). The months with the greatest possibility of seeing active turtles were recorded. Area of activity, has been estimated at 3 hectares for females and 5 hectares for males. These findings suggest a use of space that is higher than previously reported by Brown (1968) for this species. We are currently developing a monitoring program based on information obtained during the last two years of study and which will provide answers to major questions about why and where we should sample the box turtle population in the Valley of Cuatrocienegas to encourage its conservation
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