Using video to investigate relationships between environmental conditions and spawning behavior in Devils Hole pupfish

Authors: Ambre L. Chaudoin, Olin G. Feuerbacher, Scott A. Bonar, Paul J. Barrett

Year: 2012 (xliv)

Abstract

The endangered Devils Hole pupfish, Cyprinodon diabolis, lives in a single warm spring 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 cover. Disturbance events (i.e. flash-floods and earthquake activity) were identified through hydrograph data. We used multiple regression to model effects of these parameters on C. diabolis spawning activity. Initial results suggest date, diel change in dissolved oxygen, and percent algal cover significantly predicted spawning activity (P = 0.008, P < 0.0001, P < 0.0001, respectively). This study additionally provides a comparison between current remote-monitoring methods and traditional survey methods for monitoring fish behavior. Results from this study inform design of C. diabolis captive breeding programs, and demonstrate how video technologies might be more broadly applied within the aquatic sciences.