High-Throughput Microsatellite Genotypes for Desert Tortoise (Gopherus agassizii) in Ivanpah Valley (2011-2024)

Monitoring population connectivity to inform management is especially important in regions at the very edges of wilderness where native fauna and flora face habitat reduction, degradation, and fragmentation. One such region is the Ivanpah valley along the California/Nevada border, where development (i.e., solar facilities, recreational utility vehicle use) continues to encroach on the habitat of its inhabitants, including the iconic Mojave Desert tortoise, Gopherus agassizi. A long-lived, elusive animal, this species poses an array of challenges to monitoring direct movement, including the challenging terrain in which it resides and the fact that individuals can spend as much as 95 percent of their time in burrows. Thus, genetic monitoring of gene flow and population structure can be an ideal complement to direct monitoring of tortoise movement. Our group has previously evaluated the spatial population genetic structure of the tortoise in the Ivanpah region using a dataset of 299 individuals sampled between 2011 and 2019 and genotyped at 20 microsatellite loci (Dutcher et al., 2020). We found support for historical gene flow with isolation-by-resistance and suggested that connectivity may have been reduced by a railway and highway bisecting the region. We continued to follow up on these findings, collecting additional samples and developing a set of 125 high-throughput microsatellite loci designed specifically for G. agassizi. This data release contains multilocus genotypes collected by high-throughput genotyping for 722 tortoises collected in the region and will be used to explore fine-scale population genetic dynamics, reconstruct pedigrees, and infer movement patterns.