摘要:

The pallid shinerNotropis amnis, a rare minnow with an unknown life history, was collected from the Kankakee River, Illinois, over a 9-year period (1978–1986). The total length (L, mm)-weight (W, g) relationship for 88 specimens was log10W= –4.97 + 2.87(log10L). Condition factors (K= 105W/L3; mean, 0.69; range, 0.53–0.83) for specimens collected in July and August showed no trend by size and were lower than those of specimens collected in November. The annual catch per unit effort of juvenile pallid shiners (≤36 mm TL) was positively correlated with minimum flows in May and June, and negatively correlated with March air temperatures. The total catch was positively related to March maximum flow. Habitat suitability curves indicate that this species occurs in shallow areas with little or no current velocity and in moderately clear waters that are average in pH and warm and well oxygenated in summer. Juvenile pallid shiners occurred in shallower and more turbid waters than adults. Pallid shiners were associated with 45 other fish species. A cluster analysis, based on habitat and water quality variables associated with cyprinids, indicated that both juvenile and adult pallid shiners were found in conditions most similar to those of the bullhead minnowPimephales vigilax.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1991)120<0106:ECOANP>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Standardized trap and hook-and-line collections were made annually at four areas of reef habitat off South Carolina during 1983–1987 for red porgyPagrus pagrusand vermilion snapperRhomboplites aurorubens. We calculated mean annual values for catch per unit effort, estimated mean individual weights, and derived percentages of fish that were smaller than previously recommended yield-per-recruit critical lengths based on data from the two gear types. Although the two gear types did not generate identical results, there are indications that stocks of these reef fishes are overfished. The ratio of vermilion snapper to red porgy in hook-and-line samples increased during the study and in comparison to historical data, suggesting that abundance of red porgy declined more rapidly than that of vermilion snapper.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1991)120<0116:SOVSAR>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Physiological characteristics and survival of striped bassMorone saxatiliswere evaluated during, and for 1 month after, transportation from a soft-water hatchery (hardness, 28 mg/ L) to a hard-water hatchery (hardness, 110 mg/L). Fish were transported and allowed to recover in either 1.0% sodium chloride, 0.1 % calcium chloride, or fresh water. The addition of 1.0% sodium chloride to the transportation and recovery waters increased survival, decreased the rise in plasma cortisol and plasma glucose concentrations, and reduced osmoregulatory dysfunction. The addition of 0.1% calcium chloride to the transport and recovery media or the use of fresh water did not significantly reduce the stress response of striped bass during and after transport. Striped bass had significantly better survival and lower stress response when transported and allowed to recover in 1.0% sodium chloride than when treated in fresh water or 0.1 % calcium chloride, which is generally used in soft-water hatcheries to increase the water hardness.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1991)120<0121:IOWHAS>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Previous studies have shown that mummichogsFundulus heteroclitusinhabiting Piles Creek, a polluted tributary of the Arthur Kill in Linden, New Jersey, do not grow as well as conspecifics from more pristine habitats. Our study was designed to investigate whether or not reduced prey capture ability contributes to the impaired growth in the pollution-stressed population. When presented with juvenile guppiesPoecilia reticulataas food, the mummichogs from Piles Creek did not capture them as effectively as did fish from a reference site in Southampton, New York. Furthermore, field-collected specimens from the reference site showed both greater body weight for a given length and fuller stomachs than Piles Creek specimens. Gut contents of Piles Creek fish consisted primarily of detritus and sediments, whereas those of the reference fish were largely crustacean remains. Thus, the reduced growth in the Piles Creek population may be due in part to reduced feeding rate.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1991)120<0127:NRIPCA>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659-120.1.130

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor