Martin A. Kjelson

Description and Evaluation of a Long-Haul Seine for Sampling Fish Populations in Offshore Estuarine Habitats

A long-haul seine was designed to sample 10,000 m2 of open water less than 3.5 m deep for both pelagic and semi-demersal fish populations. The net, 354 m long constructed of 20 and 25 mm bar mesh. was used to encircle the area, and by a simple method to concentrate and purse the catch in open water. Atlantic menhaden, Brevoortia tyrannus; Atlantic thread herring, Opisthonema oglinum; pinfish, Lagodon rhomboides; and striped mullet, MugU cephalus were the most abundant species collected from 60 samples taken during 1973 in the Newport River estuary (Carteret County, North Carolina). Sample...


Description and Evaluation of a Portable Drop-Net for Sampling Nekton Populations

An improved design of a portable drop-net is presented. The drop-net was used to sample estuarine nekton populations whose densities were later determined by the DeLury regression method. The drop-net samples provided mean density estimates that were 4-33% of the DeLury estimate for pelagic fishes, 50-100% for semi-demersal and demersal fishes, and 82-100% for macrocrustaceans (crabs and shrimp). The degree of variation between drop-net samples depended on the species, with the greatest variation seen in samples of pelagic fishes. We concluded that there were no important differences in...