This study was made to estimate seasonal abundance, growth, mortality and biomass of planktivore fish by species and age groups
on Lake Washington, Lake Sammamish, and Chester Morse Lake, and to incorporate this information with other studies to test trophic dynamics models. Work in the initial year was directed toward...
Macroinvertebrates were sampled on a regular basis from March to October
1973. A relationship between chironomid length and biomass was established.
Production equations to be used for these insects are reported. A similar
length/weight relationship is presently being explored for the oligochaetes.
A proposal is made for calculating their production...
A steady-state phosphorus cycle was determined for the stratified period
May to November in Lake Sammamish, Washington. A steady-state. condition
for this period is considered at this time since data on some important
processes are only sufficient to estimate average values for the stratified
period. Nevertheless, such a cycle is...
Grazing rates and density of the crustacean zooplankton were measured
in Findley and Chester Morse Lakes and Lake Sammamish, Washington.
Sample analysis is incomplete at reporting time, thus estimates of
production from examination of life stage biomass changes was not possible.
Maximum density of crustacean zooplankton was about 10/1 in...
Lakes Findley, Chester Morse and Sammamish, Washington, are characterized
by one major outburst of phytoplankton productivity and biomass (mainly
diatoms) with usually no or low fall activity. Vernal outbursts were often
delayed in some lakes and years probably by unfavorable climate (snow cover
and cloudy rainy conditions). Mean spring-summer productivity...
Zooplankton grazing rates and life history stage densities for secondary
production estimates were determined in three lakes in the Cedar River
watershed, Washington. Eight copepod species, seven cladoceran and nine
rotifer species were identified in the three lakes. No one species of
cladoceran or copepod occurred in all the lakes,...
Lakes Findley, Chester Morse and Sammamish, Washington, are characterized
by one major outburst of phytoplankton productivity and biomass (mainly
diatoms) with usually no or low fall activity. Vernal outbursts were
often delayed in the monomictic lakes by inadequate light because of
unfavorable climate and/or a lack of thermal stratification. Strong...
Sample collection to define the phytoplankton biomass and productivity in Lakes Findley, Chester Morse, and Sammamish was conducted according to the schedule In Figure 1. Methods and procedures are the same as those
used in 1972 (Welch et al. 1972). The purpose of such sampling is to provide validation data...
To determine productivity of fish, we will require an estimate of relative abundance that can be expanded later into estimates of biomass. Our work has shown that much of the fish production in Lake Washington is in the form of nonsalmonid and nongame species, such as peamouth and northern squawfish....
The Washington Cooperative Fishery Unit at the College of Fisheries, University of Washington, Is carrying on studies of fishes in Lake Washington as part of the International Biological Program sponsored by
the National Science Foundation. One of our interests Is. in the effects of temperature on the movements of fishes...
Nitrogen fixation rates were determined periodically by the acetylene
reduction technique at three depths in each of the lakes. Fixation began
in June in Lakes Washington and Sammamish and peaked during July and
August. Chester Morse and Findley Lakes did not exhibit acetylene
reduction activity until August and the rates...
The purpose of the past year's research was to begin measurement of the respiratory metabolism of zooplankton and phytoplankton in four lakes in the Lake Washington drainage. This was done, using an enzyme assay for the activity of the electron transport system. The lakes were sampled frequently and depth profiles...
The preliminary results of a study of the insect emergence at Findley Lake in the Cascade Mountains of Washington during 1972 are presented. Bottom samples were taken from different regions of the lake to compare
the insect emergence at the surface, the physical conditions of the bottom,
and the biological...