L. T. Fries

A Forensic Tool Application: Distinguishing Wild from Cultured Fish

Effective 31 December 1990, the sale of wild-caught red drum was banned in the state of Texas. Practical enforcement of this legislation required the use of a technique that could unambiguously discriminate between wild and farm-raised fish. Fatty acid profiles were established for wild red drum from 4 major Texas bay systems as well as from 2 aquaculture ventures to determine if this technique could be a useful enforcement tool. Results indicate that fatty acid compositions, especially levels of linoleic acid (18:2n-6) and arachidonic acid (20:4n-6), can be useful to distinguish between...

Identification of Morone Species and Congeneric Hybrids using Isoelectric Focusing

The 4 North American species of the genus Morone were evaluated using isoelectric focusing for determination of species specific protein phenotypes. Each species could be characterized by a pair of protein bands that had isoelectric points in the 3.0 to 5.0 pH range. These diagnostic protein bands were then used to successfully identify 3 congeneric hybrids. The technique of isoelectric focusing yields results that are accurate in determination of species within this genus and serves as a powerful complement to other electrophoretic techniques in analyses of Morone populations.

A Forensics Program for Identification of Fish and Wildlife Species

As a part of a cooperative effort between the Fisheries and Law Enforcement Division of the Texas Parks and Wildlife Department, a comprehensive program for forensic identification of fish and wildlife species has been implemented. Results of comparisons of blood stains from various wildlife species indicate that isoelectric focusing of blood produces genetic "fingerprints" that are characteristic for individual species. Results of 3 representative cases are reported and the program enactment is outlined.

Natural Reproduction of White Bass x Striped Bass Hybrids in a Texas Reservoir

Natural reproduction of hybrid striped bass (Marone chrysops x M.saxatiUs) was documented in Lake Palestine, Texas. Electrophoresis and isoelectric focusing analysis indicated 29% of the sampled Marone spp. were non F-l hybrids. These individuals apparently resulted when F-l hybrids reproduced with white bass and/or F-l hybrids. Age analysis revealed the non F-l hybrids were from years when hybrid striped bass were not stocked.