A. G. Eversole

Influence of River Discharge on Blueback Herring Abundance

Adult and larval blueback herring (Alosa aestivalis) were sampled in the Santee River, South Carolina, during 1983 and 1984 under different discharge regimes. Discharge and water temperature were less variable in 1984, when at least 2 distinct peaks in abundance of adult herring were observed compared to 1 major peak in 1983. Adult and larval herring were more abundant in 1984 than 1983. The major contributor to larval abundance in 1984 appeared to be the later-occurring peak in adult herring abundance. Abrupt changes in discharge and water temperature in 1983 appeared to adversely impact...

Biology of Redbreast Sunfish in Beaver Ponds

Redbreast sunfish (Lepomis auritus) is an abundant member comprising 30% of total biomass of the fish community in beaver ponds in piedmont South Carolina. Total length-weight relationship for 534 redbreast sunfish collected from 36 beaver ponds was: 10g10Wg = - 5.06 + 3.12 log10TLmm• Mean back-calculated TL for age classes I-V were 41,75, 102, 128, and 147 mm, respectively. Growth of males was faster than the growth of females, and males appeared to have better survival. Sex ratio favored males 1.00: 1.32. Redbreast sunfish spawned from May through August after water temperatures...

Occurrence and Distribution of Larval Fish in a Coastal Plain River System

Twenty-two larval fish taxa were collected from Wee Tee Lake, a backwater tributary of Santee River, South Carolina, and 2 adjacent main river sites during the spring of 1981 and 1982. Pomoxis spp., Alosa aestivalis, Dorosoma petenense, D. cepedianum, and Perca flavescens were the most abundant species collected in both Wee Tee Lake and Santee River during both years. These species were significantly (P < 0.05) more abundant in the lake than in the river, indicating a better spawning habitat in the lake. A. aestivalis and D. cepedianum appeared to spawn concurrently and exhibited...

Age, Growth, and Sex Ratio of American Eels in Charleston Harbor, South Carolina

Age, growth, and sex ratio were determined from 484 yellow-phase American eels (Anguilla rostrata) collected from brackish waters (16.4 g/liter; mean salinity) in Charleston Harbor, South Carolina. Eels averaged 4.4 years, 437.6 mm total length, and 189.9 g live wet weight. Length-weight relationship was: log W = -5.7156 + 3.0067 log L. Length and weight increases were greatest in the third and fifth year of age, respectively. The population consisted of 85.5% mature females, 7.9% advanced females, and 6.6% males. Mature and advanced females averaged 1.6 and 3.1 years older than males (2.7...

Toxicity of Mirex to Postlarval and Juvenile Freshwater Prawns

Postlarval and juvenile prawns (Macrobrachium rosenbergii) were exposed to 7 mirex concentrations plus control for 96 hours. Static acute toxicity tests were conducted at 28 C using deionized water reconstituted to hardnesses of 11, 42, 160 and 300 mg/l as CaC03 with postlarvae and 42 mg/l with juveniles. No statistical differences were observed in survivals of postlarvae or calculated median lethal mirex concentrations among hardnesses. A 96-hour LC50 for all postlarvae was 33.9 µg/l and for juveniles 900.8 µg/l mirex. Postlarvae and juveniles exposed to 1000 µg/l accumulated mirex up to...

Helminth Parasites of American Eels From Brackish Water

Two hundred fourteen of 218 American eel, AnguiUa rostrata, from brackish portions of Cooper River, South Carolina, were infected with 1 or more of 22 helminth species representing 4 classes: Trematoda, Cestoda, Nematoda and Acanthocephala. Larval nematodes (Contracaecum sp.) predominated, infecting 95% of eels examined. Seasonal, size- and age-related variations in levels of parasitism by trematodes and cestodes are discussed. Six new host and 7 new locality records are established.

Distribution of Spawning Blueback Herring on the West Branch of Cooper River and the Santee River, South Carolina

The distribution of spawning blueback herring was determined on the West Branch of Cooper River and on the Santee River, South Carolina. On the West Branch of Cooper River, the main river channel and abandoned ricefields were utilized for spawning. The use of tributaries for spawning was limited. On the Santee River, the main river channel and tributaries were utilized for spawning. Ranges for selected physical and chemical water quality characteristics associated with the distribution of spawning blueback herring were determined from 9 Cooper River and 15 Santee River sampling stations...