The Relationship Between Energy and Burrowing Behaviors of the Red Swamp Crayfish (Procambarus clarkii)

Abstract

The Red Swamp Crayfish (Procambarus clarkii) is a globally invasive species whose burrowing behavior contributes to bank destabilization, increased sedimentation, and altered aquatic habitat structure. Despite the ecological significance of burrow construction, the energetic demands of this behavior have yet to be investigated. In the first chapter, I examined whole-body caloric density in crayfish that burrowed and crayfish that remained in individual tanks to fast. I found that neither burrowing to 32 cm nor fasting for 8 days resulted in a significant loss of energy, indicating that burrowing is not energetically expensive to this depth. However, individuals that failed to initiate a burrow showed significantly lower energy reserves after only two days, suggesting that there is a rapid decrease of energy at the surface due to some activity by the crayfish. In the second chapter, experimentally manipulating crayfish energetic condition revealed that high-energy crayfish dug deeper burrows than low-energy individuals and that the hepatopancreas’ moisture content was negatively correlated with caloric density, supporting its use as a proxy for energetic health. These findings demonstrate that while burrowing does not substantially deplete caloric densities, the initial energetic state prior to burrowing has a strong influence over burrowing performance.