Lake Trout Movements in Northwestern Lake Michigan

Abstract

We quantified the distance that lake trout Salvelinus namaycush moved in northwestern Lake Michigan and examined (1) the directional preference and (2) the effect of population density on movement. Lake trout were captured in spring and fall 1983–1996, tagged with Floy anchor tags, and recaptured during subsequent agency sampling and by commercial fishers and anglers during 1983–1997. Angler recaptures were used to quantify movements; these recaptures were standardized to 10,000 salmonid angler‐hours (giving recaptures per effort (RPE)) to account for the spatial and temporal variation in recapture effort. Movement was inferred from the spatial and temporal differences in the distribution of RPE. The dispersal radius, an index of the area occupied by tagged lake trout, was defined as the area containing 90% of the total RPE. It was estimated by fitting the cumulative proportion of RPE versus distance from the tagging location to an exponential sigmoid model and using inverse prediction. We used linear regression to test for density dependence in movement. Lake trout tagged in spring occupied a larger area than those tagged in fall and increased their range as population density increased. Directional movement differed for spring‐ and fall‐tagged fish. Spring‐tagged fish showed no directional tendencies in movement, but fall‐tagged fish tended to move more to the south than to the north. There was no significant difference in directional movement between recapture seasons. Our results will be useful for the management and restoration of lake trout in Lake Michigan by providing information that can be incorporated into population models and management decisions about refuges and management zones within the lake.

Fish movement and migration studies in the Laurentian Great Lakes: Research trends and knowledge gaps

“…), lake trout Kelso and Gardner, 2000 Habitat use, reproductive biology, invasive species Lake Superior Radio telemetry Sea lamprey Kelso, 1976 Environmental relations and disturbance Lake Erie Acoustic telemetry Yellow perch, white sucker (Catostomus comersoni) Kelso, 1974 Environmental relations and disturbance Lake Ontario Acoustic telemetry Brown bullhead (Ameiurus nebulosus) Kelso and Kwain, 1984 Reproductive biology Lake Superior Acoustic telemetry Rainbow trout Kelso et al, 2001 Invasive species Carp River, Ontario; Lake Superior Radio telemetry Sea lamprey Kelso and Noltie, 1990 Invasive species, barriers and fish passage Carp River and Pancake River, Ontario Mark-recapture Pink salmon (Oncorhynchus gorbuscha), coho salmon, Chinook salmon Kennedy et al, 2005 Reproductive biology St. Marys River, Michigan Gill net Pink Salmon Klingler et al, 2003 Reproductive biology Lake Superior tributaries Trap Rainbow trout, longnose sucker (Catostomus catostomus), white sucker, rainbow smelt (Osmerus mordax) Kocik and Taylor, 1987 Diet and trophic niche Lake Huron Angling Pink salmon Kusnierz et al, 2009 Reproductive Newman et al, 1999 Habitat use Lake Superior Radio telemetry Brook trout Noltie, 1990 Reproductive biology, environmental relations and disturbance Carp River, Ontario; Lake Superior Mark-recapture Pink salmon Porto et al, 1999 Invasive species, barriers and fish passage Lake Ontario Mark-recapture Various (n = 42) Pratt et al, 2009 Barriers and fish passage Big Carp River, Ontario PIT tags Rainbow trout, white sucker, rock bass Pycha and King, 1967 Stocking Lake Superior Mark-recapture Lake trout Pycha et al, 1965 Stocking Lake Superior Mark-recapture Lake trout (continued on next page) 369 Rahrer, 1968 Reproductive biology Lake Superior Mark-recapture Lake trout Ray and Corkum, 2001 Invasive species, habitat use Lake Erie Mark-recapture Round goby Romberg et al, 1974 Environmental relations and disturbance Lake Huron, Lake Michigan Mark-recapture Brown trout, rainbow trout, lake trout, brook trout, chinook salmon coho salmon, common carp Rybicki and Keller, 1978 Reproductive biology Lake Michigan Mark-recapture Lake trout Savitz and Treat, 2007 Reproductive biology Lake Michigan Radio telemetry Smallmouth bass, largemouth bass (Micropterus salmoides) Schmalz et al, 2002 Stocking Lake Michigan Mark-recapture Lake trout Schreer and Cooke, 2002 Environmental relations and ...…”

“…These mark-recapture data have been used widely to investigate the distribution and dispersal of hatchery-reared fish (Pycha et al, 1965;Schmalz et al, 2002). Information about when and where fish leave and return to stocking locations can help determine their contributions to respective fisheries and populations (Pycha and King, 1967;Swanson, 1973;Elrod et al, 1996;Schmalz et al, 2002).…”

“…These mark-recapture data have been used widely to investigate the distribution and dispersal of hatchery-reared fish (Pycha et al, 1965;Schmalz et al, 2002). Information about when and where fish leave and return to stocking locations can help determine their contributions to respective fisheries and populations (Pycha and King, 1967;Swanson, 1973;Elrod et al, 1996;Schmalz et al, 2002). For example, Pycha et al (1965) investigated the vertical distribution, dispersal, and return of hatchery-reared Lake Trout and found that neither shore nor boat stocking in inshore waters is effective for stocking offshore areas and that lake currents play an important role in fish dispersal.…”

“…For example, Pycha et al (1965) investigated the vertical distribution, dispersal, and return of hatchery-reared Lake Trout and found that neither shore nor boat stocking in inshore waters is effective for stocking offshore areas and that lake currents play an important role in fish dispersal. More recently, Schmalz et al (2002) estimated Lake Trout movements using mark-recapture techniques and found that although stocking increased the number of Lake Trout, stocking may not increase the local population density because stocking densities influence dispersal.…”

Contribution of lake trout stocked as fry to an adult population in Lake Superior

“…Kapuscinski et al (2005) documented that lake trout moved a mean distance of 42 km throughout the year in U.S. waters of Lake Superior. Lake trout in northwestern Lake Michigan had dispersal radii of about 57-68 km (Schmalz et al, 2002). Our entire study area extended 60 km from Stony Point to Silver Bay, and thermally marked lake trout were recaptured throughout the entire range.…”