Seasonal Variation in Home Range Size and Habitat Use of Flathead Catfish in Buffalo Springs Lake, Texas

Abstract

Ultrasonic telemetry was used to determine the seasonal variation in the home range size of and habitat use by adult flathead catfish Pylodictis olivaris in a 93-ha reservoir in West Texas. Home ranges were significantly smaller in winter than during summer for both males and females combined. Neither fish size or sex influenced home range size. Flathead catfish used substrates with a hard bottom, such as gravel, rocks, and large boulders, during all seasons and woody cover, such as standing timber and artificial structures, during all seasons except winter. Flathead catfish were found at shallower depths in spring and summer (1.0–4.9 m) than during late fall and winter (>5.0 m). Flathead catfish moved to deeper water in late fall when mean surface temperatures were between 14.0 and 22.0°C. Our results suggest that flathead catfish movement decreased during winter and that hard substrates are important habitat for this species.