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L.L. Pugh

Publications and source records attributed to L.L. Pugh.

2 recordsLinked to original sources

Segmentation of Mississippi’s natural and artificial lakes

Segmentations divide a diverse resource into groups, or segments, based on distinctive attributes that may respond similarly to management actions. A 4-way segmentation based on lake origin (natural or artificial) and size (small or large) was constructed for Mississippi lakes using a 30 yr data set. We aimed to document elements distinguishing these segments to understand relationships among them and to seek insight into lake management that may be apparent at the segment scale but not at the lake scale. Analyses pinpointed differences among the 4 segments relative to nutrient levels, fish assemblage composition, fishery characteristics, angler catch, and fishery management objectives. In general, most artificial lakes were eutrophic, varied widely relative to species composition depending on whether they impounded small or large rivers, their fish assemblages could be heavily influenced by stocking, provided principally centrarchid fisheries, and the management focus was on angler harvest. Most natural lakes were hypereutrophic, included higher species richness, provided a greater diversity of fisheries, and the management focus was on fish populations and habitat. Fishing success was similar across segments. The group-wise differences substantiate the segmentation and bring into focus a new level of concepts not typically relevant when considering lakes in isolation, such as issues about lake quantities, similarities, and geographical distributions. The segmentation represents the framework needed for considering lakes as parts of a larger and interactive management system.

Mississippi

Relationship between vegetation coverage and abundance, size, and diet of juvenile largemouth bass during winter

Juvenile largemouth bass Micropterus salmoides were collected by electrofishing during October through March 1992–1994 from coves (≤25 ha) covered with aquatic macrophytes over 1–65% of their area. Mean total length of juvenile largemouth bass was highest in coves with the least vegetated cover, but increase in mean length between October and March was highest in coves having near 20% vegetation coverage. Catch per unit effort decreased between October and March; decreases were least at vegetation coverages near 10–20%, highest at coverages of 5% or less, and intermediate at coverages of 30–65%. By March, these disparate decreases contributed to the formation of a dome-like relationship between vegetation coverage and catch per unit effort. Consumption of fish foods was highest when vegetation coverage was low, but decreased asymptotically as coverage increased; consumption of invertebrate foods increased at low coverage, peaked near 20–30% coverage, and decreased at higher coverage. We suggest that greater length increases and greater abundance at 10–25% vegetation coverage were stimulated by a favorable blend of food availability and cover. Our results support reports that maximum recruitment of largemouth bass occurs at intermediate levels of vegetation coverage, and we further suggest that such increased production is reinforced during winter, when survival. invertebrate consumption, and length increases are highest at intermediate levels of vegetation coverage.

Alabama, Mississippi