Use of Multiple Spawning Sites and Seasonal Movement by Razorback Suckers in the Middle Green River, Utah

Abstract
Radiotelemetry data through three successive spawning events (1993–1995) and capture data for 15 years (1975, 1979–1993) were used to describe movement patterns and fidelity to spawning sites by male razorback suckers Xyrauchen texanus in the middle Green River, Utah. Movement to spawning areas was influenced primarily by discharge. The greatest distances traveled by male razorback suckers were in a downstream direction and occurred just before and shortly after spawning. Three of six surviving males implanted with radio transmitters were located on more than one spawning site between 1993 and 1995. Thus, although most razorback suckers in the middle Green River spawned in a single area between river kilometers 492 and 501 (from the confluence of the Green and the Colorado rivers), other spawning areas were probably used. Tag recapture and telemetry data supported the hypothesis that razorback suckers in the middle Green River represent a single reproductive population.