IDENTIFICATION OF HATCHERY-REARED CHANNEL CATFISH BY MEANS OF PECTORAL SPINE CROSS-SECTIONS

Authors
Citation
Gl. Siegwarth, IDENTIFICATION OF HATCHERY-REARED CHANNEL CATFISH BY MEANS OF PECTORAL SPINE CROSS-SECTIONS, Transactions of the American Fisheries Society, 123(5), 1994, pp. 830-834
Citations number
19
Categorie Soggetti
Fisheries
ISSN journal
00028487
Volume
123
Issue
5
Year of publication
1994
Pages
830 - 834
Database
ISI
SICI code
0002-8487(1994)123:5<830:IOHCCB>2.0.ZU;2-C
Abstract
Cross sections of pectoral spines were used to identify hatchery-reare d and wild channel catfish Ictalurus punctatus in the Buffalo River, A rkansas. Stocked, catchable-size catfish could be identified by wide g rowth increments between the first and second annuli (corresponding to rapid hatchery growth) followed by narrow annual increments beyond ag e 2 (corresponding to slower posthatchery growth). For stocked fish, t he mean width between the first and second annulus of the spine sectio n was 3.4 times wider than the mean width between the second and third annulus. In wild fish these widths were not significantly different. This growth pattern for stocked fish was verified by using pectoral sp ines obtained from marked hatchery fish stocked in 1990 and 1991, and by comparing back-calculated lengths of suspected hatchery fish at age 2 with the length at stocking. By the use of this method, it was dete rmined that previously stocked catfish accounted for more than 92% of the catfish sampled in the Buffalo River. This technique should be app licable in other regions if catchable-size channel catfish are being u sed in stocking programs and if the growth rate for hatchery fish exce eds that of wild fish.