US Long-Term Ecological Research Network
Fish Sampling
Fish sampling was conducted on each lake at least one month after thermal stratification had taken place, beginning on the 3rd week in June and running through the 3rd week in July. This was done to minimize the effects of winter stress and spawning on fish weight given their length. Several gears were employed to estimate fish diversity in each lake, each being effective at catching a different set of fishes.
Vertical gillnets were employed to sample pelagic fishes. A spectrum of mesh sizes (19, 32, 51, 64, 89-mm stretch mesh) were used, with each mesh size effectively catching a different size range of fish. The nets were fished in the deep basin of each lake for one diel cycle.
Fyke nets were employed to sample fishes in the shallow near shore areas. Mini fyke nets with a mouth opening 0.75-m high by 1.25-m wide constructed with 4-mm delta mesh, with a 1-m by 5-m single lead were set so as the lead ran perpendicular from shore and that the mouth sat in approximately 1-m of water. There were 3 nets set at differing locations defined by substrate type (muck, sand and cobble) for one diel cycle. Three crayfish traps were set along side each of the fyke nets so as to sample the same habitat type sampled by each fyke net.
Electrofishing occurred in the near shore area between 0.3 and 1.5-m in depth. Two 30 minute transects were performed such that a variety of substrate types were sampled. The dipnets used to net fish during electrofishing consisted of 4-mm delta mesh and were capable of retaining small fishes (down to 20-mm). Our goal was to capture and identify as many game and non-game fish species as possible.
 
Fish Processing

Fish caught in each gear type were processed by measuring mass and total length of all fish of each species; however, a subset of each species was measured when the catch rate was high. Two fish in each 5-mm size class for each species were weighed and length measurements were taken so as to collect weight measurements for a wide size range of each species. If the catch of a given species in a given size class (small, medium or large) within a particular set or electro-shocking run exceeded 30 fish, 30 were measured for each species. Those not measured for length in each size class were counted and recorded so as to associate them with those that were measured to allow length frequency distributions to be generated while expediting our processing and avoiding redundant weight and length measuring. Each fish was identified to genus and species using the taxonomic key in Becker (1983). Any game fish killed were turned over to the appropriate Department of Natural Resource Game Warden.

LTER Keywords
Protocol Format
Process
Protocol ID
lpp_fish1
Protocol Type
field