Genetic Structure and Movements of Angler-Caught Trophy Largemouth bass as Determined through a Privately-Sponsored Catch and Release Program

Ryan, M. J. and M. W. Brice, Texas Parks and Wildlife Department, 3802 East End Blvd. S., Marshall, Texas 75672

Fries, L., Texas Parks and Wildlife Department, A. E. Wood State Fish Hatchery, 507 Staples Rd., San Marcos, Texas 78666

Largemouth bass (> 3.6 kg) entered into a trophy catch and release program sponsored by Bass Life Associates (BLA) at Caddo Lake (10,854 ha) were used to determine the percentage of recaptured entries, movement based on angler-reported catch locations, and genetic composition. One hundred and sixty seven largemouth bass entries were pit-tagged and released at participating marinas between February 15, 1997 and May 31, 1999. Following initial tagging, largemouth bass entries were scanned to determine if they had been previously tagged. Blood samples were obtained from initial entries and used to determine genetic composition using randomly amplified polymorphic DNA. Anglers entering a bass into the program were asked to identify the location of their catch on digitized-grid maps. Catch locations of recaptured bass were used to assess movements of fish following release. Sixty-seven percent of the trophy bass entered into the program were caught during the months of March and April. Of the 167 fish tagged, 18 fish (10.8%) were recaptured at least once and 4 (2.4%) were recaptured twice. The distance between initial and recapture locations ranged from 0.3 and 7.2 km (mean = 2.7 km) and corresponding time intervals between catches for individual fish ranged from 9 to 457 days (mean = 192 days). Most of the initial and recaptured largemouth bass entries (85%) were caught in the middle portion of Caddo Lake (approximately 2500- to 3000 ha), suggesting possible habitat preferences and/or homing tendencies. Genotypic composition of the BLA entries was 12.9% (N = 11) Florida largemouth bass, 41.76% (N = 38) F1 intergrade, 43.96% (N = 40) later generation and backcross intergrades, and 2.2% (N = 2) northern largemouth bass. Considering the size of Caddo Lake and the fact that tagging was conducted over a 3-year period, percentage of recaptures was most encouraging and suggests BLA’s program has contributed to the fishery by recycling trophy bass. BLA’s catch and release program provided a more efficient means of gathering data on trophy largemouth bass compared to electrofishing sampling. Largemouth bass > 580 mm (N = 167) were collected at a rate of 0.50 fish/man hour (total man hours = 336) during this study compared to 0.02 fish/man hour (N = 3) in 144 man hours expended during electrofishing collections over an eight year period. The program also provided a means through which the sponsor, anglers, and TPWD biologists could work together in a cooperative environment to monitor direct benefits of the angler incentive program and gather genetic and life history information on rare and valuable trophy largemouth bass.

Copyright © 1999
Texas Chapter of the American Fisheries Society
Last modified: 03/03/04 04:15:38 PM