STUDIES OF THE ECOSYSTEM OF LAKE GEORGE, ALASKA.
Abstract
Lake George is a relatively shallow (maximum depth 11 m), eutrophic lake about 18.44 sq. km. in surface area, formed by aggradative damming of a tributary valley by the Tanana River during post-glacial times. Warming of the water is rapid in the spring and reaches a maximum in early July about five to six weeks after ice cover is gone. A relatively unstable thermocline forms and sinks gradually to a depth usually between 8 and 10 m. The euphotic zone extends to the bottom, and the water, under appropriate wind conditions, can probably mix completely at any time during open-water season. Parasitic fauna is relatively poor in comparison with temperate zone lakes. Occurrence of more than one life cycle stage of six helminth parasites was confirmed, suggesting a degree of autonomy in the ecosystem in maintenance of life cycles. Environmental temperature extremes which are faced by aquatic poikilotherms are faced by their parasites as well. Experiments were conducted using a Cartesian diver microrespirometer and metacercaria of Diplostomum (Trematoda; Digenea) from the eyes of fishes, which support the hypothesis that parasites can adjust their metabolic rate appropriately to a given temperature regime.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1966
- Accession Number
- AD0635157
Entities
People
- L. G. Swartz
Organizations
- University of Alaska Fairbanks