Cooperative Fish and Wildlife Research Units Program: Arizona
Education, Research and Technical Assistance for Managing Our Natural Resources

Significant phenotypic plasticities have been observed previously in pupfishes when grown under differing environmental conditions. The mechanisms of phenotypic plasticity are being studied in a variety of ways. Phenotypic, behavioral, genomic, and gene expression characteristics will be measured over multiple generations between populations reared under “ideal” hatchery conditions and under simulated “Devils Hole” conditions. Controlled cohorts are being compared to identify the individual effects of low dissolved oxygen, low food, and combinations thereof. RNA expression profiles of developing eggs and larvae from these groups will be examined to identify if the plasticity is controlled at an expression level, and SNP microsatellite profiles of the progeny will be compared to those of the parental fish to determine if these environmental conditions can hasten genetic drift. A small-scale reproduction of Devils Hole is being utilized to mimic as closely as possible, both the biotic and abiotic factors present in Devils Hole. A greater than 3000-gallon system has been installed to create a simulated ecosystem with the characteristic low dissolved oxygen, high temperatures and minerals, and highly variable seasonal lighting. A spawning shelf is included and zones within the system can be individually controlled to simulate the seasonal variations found in Devils Hole. The system is also plankton-friendly, and is stocked with organisms representative of those commonly observed in Devils Hole. Field and laboratory work on this project is underway. Similar analyses of the population genomes and RNA profiles will be analyzed. Cameras in the tank will allow for both day and night behavioral observations which can be compared to the field observations captured by cameras installed in Devils Hole.