Skip to main content
hyi
Banner
banner
bn

LOCATION AND CHARACTERIZATION OF A SPAWNING SITE OF SISCOWET LAKE TROUT

RATIONALE:  About 9 % of the lake trout in Lake Superior are   siscowets, a deepwater morphotype and the main keystone predator.     Despite their importance, their spawning locations have not been   characterized.  In 2  9 a high-resolution bathymetry/seabed   classification map for a likely spawning area near Marquette was   produced (funded by MN Sea Grant).We will follow-up with this   project to locate where eggs are deposited and characterize the   physical habitat.  Because L. Michigan?s indigenous lake trout also   included deepwater morphotypes the proposed study is pertinent to   restoration efforts there.  Currently L. Michigan deep reefs, such   as those at the Mid-Lake Reef Complex (MLRC) are priority targets   for lake trout restoration and the only known sites where lean lake   trout are depositing eggs and producing sac-fry and fry.  While   there are suitable shallow reef reference spawning sites with self-  sustaining lake trout populations (e.g. Parry Sound, L. Huron), the   physical conditions of deep reefs may differ considerably for some   parameters such as ventilating currents, thermal regime, and effects   from storm events.  Characterization of a L. Superior deepwater   spawning site with a self-sustaining population would aid in the   evaluation of the MLRC spawning areas and locating additional areas   for lake trout restoration in L. Michigan and elsewhere.    OBJECTIVES: We will determine the spawning site characteristics of   siscowet lake trout by using the high resolution bathymetry and   substrate maps from N. Wattrus, U. MN-Duluth.  We will begin with a   bioacoustic survey of potential spawning habitat during the spawning   season to locate adult siscowets, and  ROV-based egg suction   sampling at sites where adult siscowet were found during the   spawning season.      METHODS:  For the bioacoustic survey we will use a 129 kHz (and   possibly a 7  kHz) Biosonics DT-X split beam echosounder and   Echoview software (MI-DNR task).  The ROV is a Benthos MiniRover   extensively modified so that it is able to suction-sample for eggs   and visually record individual sample events to enumerate eggs.  The   system has a tracking device (real-time GPS coordinates) and a CTD   that provides real-time depth and temperature data.   

Status
In progress
Type
Project
Start Date
End Date
Researchers
John JanssenPrincipal Investigator
Associated with 1 projects
Shawn SitarResearcher
Associated with 5 projects
Charles BronteResearcher
Associated with 2 projects
Agencies
Great Lakes Fishery Commission $ 24,411.00USDEstimates

Funding 54 projects for a total of $5,089,137.00
Scope of Study
Field Investigation
Scale of Phenomena
Organism
Population
Resource Management
Fisheries
Lake Basin Connecting Channels
Lake Superior
State Province
Michigan
Annex Numbers
Surveillance and Monitoring

The Great Lakes - St. Lawrence Research Inventory is an
interactive, Internet-based, searchable database created as a tool to collect and disseminate
up-to-date information about research projects in the
Great Lakes - St. Lawrence Region.