Comparative thermal biology and depth distribution of largemouth bass (Micropterus salmoides) and northern pike (Esox lucius) in an urban harbour of the laurentian great lakes

Understandinghowindividuals are distributed in space and time, as well ashowthey interact with dynamic environmental conditions, represent fundamental knowledge gaps for many fish species. Using acoustic telemetry tags, we monitored the temperatures and depths used by northern pike (Esox lucius L., 1758) and largemouth bass (Micropterus salmoides (Lacepède, 1802)) in Toronto Harbour (Lake Ontario). Northern pike and largemouth bass had similar thermal experiences throughout the year, except during summer, when northern pike were observed in cooler waters than largemouth bass. Both species used different depths throughout the year, with northern pike occupying deeper depths. Statistical modelling indicated that depth usage was influenced by all variables (season, species, and body size) and interactions between them, whereas thermal preferences were influenced by the main effects and interactions between species:season and species: body size. Both species were observed at temperatures warmer than those in the vicinity of nearby telemetry stations, but as station temperatures exceede

Temperature regimes, growth, and food consumption for female and male adult walleye in lake huron and lake erie: A bioenergetics analysis

Bioenergetics modeling was used to assess the relative importance of food availability and water temperature in determining walleye (Sander vitreus) growth. Temperature regimes experienced by both female and male adult walleye in three basins of Lake Huron and in Lake Erie were determined by use of surgically implanted temperature loggers and acoustic telemetry. Temperatures experienced by walleye were higher in Lake Erie than in Lake Huron. Walleye from Lake Erie grew at nearly double the rate of walleye from Lake Huron, and mass at age for adult females averaged about 50% greater than that for adult males in both lakes. Food consumption rate for an average adult walleye in Lake Erie was nearly twice as high as that in Lake Huron. Interbasin and interlake variability in temperature regimes accounted for a moderate degree of variability in walleye growth. We concluded that the driver for faster growth in Lake Erie compared with Lake Huron was higher food availability in Lake Erie compared with Lake Huron. The sex difference in temperature regimes explained 15% of the sex difference in Lake Erie walleye growth