35 - Do corridors maintain genetic diversity? A study of urban Texas Spiny Lizard populations
Habitat fragmentation results in small, isolated populations that may experience higher extinction risks. One possible solution for the conservation of fragmented populations is the creation of dispersal corridors, or habitat connections, to allow movement and gene flow between areas. In theory, corridors allow genetic diversity to be maintained, increasing the overall fitness of otherwise isolated populations. The city of San Antonio, Texas has recently set aside natural areas and connection corridors (i.e., green-belts) between natural areas for conservation purposes. These corridors provide an excellent opportunity to assess the effectiveness of corridors for maintenance of genetic diversity. Here, we study the population genetics of the Texas Spiny Lizard (Sceloporus olivaceus), to determine if lizards from populations in isolated urban natural areas are genetically less variable than those in areas connected by corridors and those in rural natural areas. I have collected tissue samples from 172 lizards from two isolated city parks, two systems of parks connected by corridors, and two rural natural populations. Using PCR, I have amplified seven microsatellite loci from the lizard DNA samples that will be analyzed with F-statistics to assess population genetic diversity. I will also determine the number of independently evolving populations represented in our sample with the program STRUCTURE. This study will contribute toward our understanding of the effectiveness of corridors in preserving genetic variation for vertebrate conservation.