Use of Fish Corrals in the Seine Fishery of the Virgin Islands

Although selected aspects of the commercial fishery in the Virgin Islands have been documented since the early 1930's (Fiedler and Jarvis, 1932; Idyll and Randall, 1959; Hess, 1961; Swingle et al. 1970; Brownell, 1971; Brownell and Rainey, 1971; Sylvester and Dammann, 1972, and Olsen et al., 1978), fish corrals and their use have not been described. This account, based on personal observations made during 1985-86, summarizes commercial fishing methods in the Virgin Islands (U. S. and British), documents the use of fish corrals, and serves as an introduction to the methodologies of this harvesting technique. Interviews of commercial fishermen about how and when fish corrals are used provided information not available from direct observation. Local common names for gear type and fish species are shown in parentheses

Fish community structure in some naturally acid Florida lakes

This study investigated the status of fish communities in 12 naturally acid Florida lakes. The small, shallow lakes were located in the Ocala National Forest, the Trail Ridge, and panhandle Florida; regions where lakes have low acid neutralizing capacities and are considered sensitive to further acidification from anthropogenic sources. Fifteen species from seven families were captured during mark-recapture sampling. Warmouth (Lepomis gulosus) was the only cosmopolitan species in the study. Bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides), collected from 11 and 10 lakes, respectively, were also widely distributed species. Total fish abundance and biomass were not related to lake pH or total alkalinity. (Document has 202 pages

Tidal management affects sub-adult fish assemblages in impounded South Carolina marshes

In coastal South Carolina, most impounded marshes are managed for waterfowl; fewer are managed for fishes. Tidal control is central to each strategy but raises concerns that nursery function could be impaired. This research examined the assemblage composition of fishes during early-life stages. We sampled two impoundments of each management type monthly in 2008 and 2009. We used light traps to collect 61,527 sub-adult fish representing 21 species and 16 families and push nets to collect 12,670 sub-adult fish representing 13 species and 11 families. The effective number of species detected at larval stage in “fish” impoundments (summer mean = 2.52 ± 0.20, winter mean = 2.02 ± 0.66) was greater than in “waterfowl” impoundments (summer mean = 1.27 ± 0.14, winter mean = 1.06 ± 0.09); CI = 90 %. Species richness did not differ between management types, but hierarchical linear models predicted differences in assemblage composition. These findings underscore the importance of frequent water exchange for maintaining diverse assemblages of early-life-stage fishes in marsh impoundments.Keywords: Light trap, Impoundment, Salt marsh, Early-life stages, Diversity, Fragmentatio

Evaluation of Three Aging Techniques and Back-calculated Growth for Introduced Blue Catfish from Lake Oconee, Georgia

Back-calculation of length-at-age from otoliths and spines is a common technique employed in fisheries biology, but few studies have compared the precision of data collected with this method for catfish populations. We compared precision of back-calculated lengths-at-age for an introduced Ictalurus furcatus (Blue Catfish) population among 3 commonly used cross-sectioning techniques. We used gillnets to collect Blue Catfish (n = 153) from Lake Oconee, GA. We estimated ages from a basal recess, articulating process, and otolith cross-section from each fish. We employed the Frasier-Lee method to back-calculate length-at-age for each fish, and compared the precision of back-calculated lengths among techniques using hierarchical linear models. Precision in age assignments was highest for otoliths (83.5%) and lowest for basal recesses (71.4%). Back-calculated lengths were variable among fish ages 1-3 for the techniques compared; otoliths and basal recesses yielded variable lengths at age 8. We concluded that otoliths and articulating processes are adequate for age estimation of Blue Catfish

Considerations for Flow Alternatives that Sustain Savannah River Fish Populations

Proceedings of the 2003 Georgia Water Resources Conference, held April 23-24, 2003, at the University of Georgia.Flows in the lower Savannah River have been considerably altered since the construction of Strom Thurmond Dam in 1954. The effects of this flow alteration on fish have received little attention until recent years. We are collaborating with The Nature Conservancy and the Army Corps of Engineers to develop flow alternatives below Strom Thurmond Dam by evaluating relations between flow regimes and specific life history stages of riverine and diadromous fishes within shoal, floodplain, and estuary habitats. Although restoring a natural flow regime to the Savannah River may not be a feasible objective, alternatives to current flow management could enhance the ability of the river to support native fish populations. Evaluations of flow alternatives should consider effects on habitat stability in the shoals, interannual and intra-annual flow variation, and provision for fish access on and off of floodplain habitats. Evaluating effects of flow alterations on estuarine habitats is complicated by the often larger effects of physical channel alteration, especially harbor deepening