Using Video to Investigate Relationships Between Environmental Conditions and Spawning Behavior in Devils Hole Pupfish

The endangered Devils Hole pupfish, Cyprinodon diabolis, lives in a single warm-pool of unknown depth within Death Valley National Park, California/Nevada.  Over the past several years, C. diabolis has reached record-low numbers, spurring renewed conservation and recovery efforts.  Though factors that influence spawning may be important in regulating C. diabolis population size, much is still unknown about the reproductive ecology of this notoriously difficult-to-breed species.  Over 11 months, February-December 2010, we monitored spawning behavior of C. diabolis and associated environmental conditions within Devils Hole.  A solar-powered video surveillance system, incorporating above-water and underwater cameras, provided continuous monitoring of the shallow spawning shelf.  Datalogging meters continuously recorded dissolved oxygen, temperature, and lux, and monthly in-person surveys recorded time-lapse algal and substrate cover.   Based on data obtained with the underwater camera, relationships between spawning and associated environmental conditions exemplify the largely seasonal spawning activity of C. diabolis.  This study additionally provides a comparison between current remote-monitoring methods and traditional survey methods in monitoring fish behavior.  The results from this study will hopefully provide information useful for designing C. diabolis captive breeding programs, as well as information on how current technologies might be more broadly applied within the aquatic sciences research arena.