Eugene W. Surber

Levels Of Phosphorus And Nitrogen In Shenandoah River Water

In the period 1936-1941, smallmouth bass nests were counted in the Main Stem and South Fork of the Shenandoah River. Counts were made during the smallmouth bass spawning season when waters were clear, usually May 1-15. Due to eutrofication, the South Fork and Main Stem water now remains clear for only a few days. The enumeration and study of bass nests has been made more difficult due to the sudden development of blooms of algae. High levels of phosphorus and nitrogen in the South and North Forks and the Main Stem are believed to be the cause. Total phosphate ranged from 0.33 to 4.80...


Procedure In Taking Stream Bottom Samples With The Stream Square Foot Bottom Sampler

A detailed description of the procedure used in taking stream bottom samples follows a description of the stream square foot bottom sampler, which, although pictured in a publication by the author in 1937, was not described in detail in any publication. One of the principal problems in retrieving bottom animals from samples is getting them quickly from the gravel without damaging them. Large stones in the sample area are removed first and placed in a pail half-filled with water. The contents of the net are also emptied carefully into the same pail. Upon reaching the shore, the pail is...


Effects Of A 12-Inch Size Limit On Smallmouth Bass Populations And Fishing Pressure In The Shenandoah River, Virginia

In 1964, five sections of the Shenandoah River ranging from 9.0 miles to 15.3 miles in length (average 11.4 miles) were selected for an airplane census of fishermen. The census was conducted on a randomized schedule2 for both days of the week and time of day for the counts, with weekend days weighted because of heavier fishing pressure on those days. These data for 1964 through 1967 were used to compute the total fishing pressure in these sections. Creel clerks were employed on a part-time basis in each of the five sections to gather information on the number of smallmouth bass, both...


Water Quality Criteria For Freshwater Fishes

Good productivity of fish and aquatic life are dependent upon clear, clean water at favorable temperatures and with sufficient concentrations of needed dissolved gases and solids. The number of individuals and species of bottom animals or plankton present in streams and lakes are important criteria of water quality. Siltation is one of the most damaging and widespread pollutants; it causes reduction of light penetration, destruction of shelter, and smothering effects on eggs. For short periods fishes tolerate turbidities up to 100,000 parts per million, but under long-term exposure,...