Publications

No abstract available.

Reproductive success was relatively consistent, and adequate to maintain species abundance at a nearly constant level, during 1963-69. Both abundance and growth in length increased from the lower to the upper portion of the reservoir. In most characteristics -- growth in length, length-weight relation, age at maturity, and food -- goldeye in Lake Oahe were similar to those from other...

Twenty-seven fish species were captured in Lake Oahe with trap nets in 1963-67. The catch was dominated by eight species in order of abundance: black crappie (Pomoxis nigromaculatus), bigmouth buffalo (Ictiobus cyprinellus), white crappie (Pomoxis annularis), carp (Cyprinus carpio), river carpsucker (Carpiodes carpio), freshwater drum (Aplodinotus grunniens), smallmouth buffalo (Ictiobus...

The bigmouth buffalo, Ictiobus cyprinellus, is the most important commercial species in Lake Oahe, a reservoir in the upper Missouri River. The population was dominated by three strong year classes (1959, 1960, and 1962). Estimated population in the fall of 1964 was 540,000 fish of the combined 1959-60 year classes and 5 million of the 1962 year class (equivalent to 81 kg per hectare)...

In the laboratory we measured the amounts of dieldrin and p,p'DDT accumulated by fish from contaminated water and food to determine how fish from Lake Michigan accumulate high concentrations of these insecticides from an environment where the concentrations in water are generally less than 0.01 ppb. Eight groups of yearling lake trout (Salvelinus namaycush) were exposed to different...

Five species of aquatic insects - two plecopterans, two trichopterans, and one ephemeropteran - usually found in streams or ponds were collected in water 32-100 m deep in western Lake Superior. All appear to be new records for the lake and all were collected from far greater depths than previously recorded for these forms.

Large trap nets were evaluated as a commercial gear for capturing buffalo fish during July-September 1965. During the 72-day fishing period, 13,171 fish weighing 21,669 kg were taken. Bigmouth buffalo (Ictiobus cyprinellus) and smallmouth buffalo (Ictiobus bubalus) dominated the catch (78.2% by weight). Eight sport species accounted for 3.6% of the total catch. Both 7.0-cm and 12.7-cm...

The benthos in Lake Oahe, as determined from about 450 bottom samples collected during the open water season in 1968 and 1969, was dominated by oligochaetes and chironomids; Caenis (Ephemeroptera) and Chaoborus (Diptera) were occasionally abundant. Total benthos was estimated at 3,600 organisms/mA? with an ash-free dry weight of about 2.2 g/mA? (about 33 kg/hectare dry weight). Estimated...

Ten species were commercially harvested in Lake Oahe, among which bigmouth buffalo (Ictiobus cyprinellus) predominated (63.8% of the total weight), smallmouth buffalo (Ictiobus bubalus) and goldeye (Hiodon alosoides) ranked second, and third. Variations in the seasonal and annual production of buffalo were governed by market conditions and availability. Production of minor species...

Trawls of various designs and sizes were compared to evaluate their use for monitoring and harvesting fish populations in Lake Oahe. Catches of a 10.7-m semiballoon trawl, selected to monitor changes in the fish populations from 1965 to 1970, showed a downward trend in the abundance of all species, except walleye; the decline was largest in the lower area of the reservoir with a slight...

The limnetic crustacean zooplankton of Lake Oahe was dominated by copepods. Cyclops bicuspidatus thomasi was the dominant crustacean throughout the lake. Mesocyclops edax, Diaptomus ashlandi and Daphnia pulex were major components of the zooplankton in the deep, downstream portion of the lake while Bosmina longirostris and Daphnia retrocurva were important constituents in the river-like...

The physical and chemical characteristics presented provide a description of Lake Oahe and establish bases for certain characteristics which may alter as the reservoir ages. Water temperatures were strongly influenced by wind-driven currents and water depth. The duration of thermal stratification varied from about 3 wk in the upstream portion of the reservoir to about 15 wk near the dam...