Skip to main content
Dryad logo

Population genetic structure Arctosa sanctaerosae

Citation

Hataway, Robert (2021), Population genetic structure Arctosa sanctaerosae, Dryad, Dataset, https://doi.org/10.5061/dryad.m0cfxpp1z

Abstract

The continued increase in the number of tourists visiting the Northern Gulf Coast (NGC), USA, in the last century, and the resulting sprawl of large cities along the coast, has degraded and fragmented the available habitat of Arctosa sanctaerosae, a wolf spider endemic to the secondary dunes of the white sandy beaches of the NGC. In addition to anthropogenic disturbance to this coastal region, hurricanes are an additional and natural perturbation to the ecosystem. The data presented here explore the status of populations of this species spanning the entire known range and the factors influencing population demography including anthropogenic disturbance and severe tropical storms. Using microsatellite markers, we were able to document the genetic structure of Arctosa sanctaerosae, including current and historical patterns of migration. These results combined with ecological and census data reveal the characteristics that have influenced population persistence: ecological variables affecting the recovery of the population clusters after severe tropical storms, genetic fragmentation due to anthropogenic disturbance, and their interaction.  These findings demonstrate the significance that the high traffic beach communities of the NGC and their impact on the once intact contiguous dune ecosystem have on recovery after severe tropical storms. Contemporary modeling methods that compare current and historical levels of gene flow suggest Arctosa sanctaerosae has experienced a single, contiguous population subdivision, and the isolates reduced in size since the onset of commercial development of the NGC. These results point to the need for monitoring of the species and increased protection for this endangered habitat. 

Methods

Tissue samples from 20 individuals collected from each of the sites were collected between June 1st and 11th 2007 to be used in genetic analyses. All individuals were stored at -80°C in 100% ethanol and approximately 1 mg of tissue acquired from the legs was used for subsequent DNA extraction (Qiagen DNeasy kit). Target microsatellite sequences were amplified using 11 microsatellite primers, ten developed for the study species (Hataway et al. 2011) and an addition developed for a sister taxa. Fluorescence-labeled fragments were visualized on an ABI 3130 and allele sizes were determined through comparison with a known size standard (GeneScan -500 ROX) using GENEMAPPER version 3.7. All scores were checked manually and ambiguous fragments were reanalyzed.