Effectiveness of light traps for capturing Razorback Sucker larvae

Abstract

Detection of endangered Razorback Sucker Xyrauchen texanus larvae by light traps is used to prompt flow releases to inundate Green River floodplains crucial to survival. However, little is known about the efficacy of light traps to capture or retain larvae. We investigated effects of trap set time, release distance from trap, light presence, and turbidity on capture and retention rates of early life stages. Laboratory capture rates were 90% and decreased 60% with increasing fish size. Retention exceeded 70% overall, but increased 25% with increasing fish size. Relationships between set time and distance should be investigated, along with field testing.