ESD Teams Up With Conservation for Spring Fisheries Surveys

The arrow indicates where one of the spines was removed for aging

 MITW fisheries biologist Richard Annamitta recently started the spring fishery surveys on several local lakes.  ESD is assisting with the effort which  includes electrofishing and fyke net surveys.  What does a fishery survey do for us?  Fishery surveys allow the fisheries biologist to determine the health, size structure, density of the fish population.  The type of survey we are using here is the mark and recapture survey.  This is done by capturing fish and tagging them with floy tags.  Floy tags are small cylindrical tags with a number on it for identification purposes.  All of the marked fish are released back into the lake.  The recapture run is done anywhere from one to three days after the fish are released.  The number of tagged fish versus the number of untagged fish are then entered into a formula to calculate the number of that species of fish in the lake.  When this information is routinely gathered the population can be monitored and the information is used to help guide management decisions.  The goal is to have healthy fish populations which can provide a quality fishing experience for fishermen.  The lakes being electrofished this year are Burney, Elma, Hazel and Crowell.  The early surveys are used to determine the success of the walleye stocking program that has been ongoing.  The panfish and bass populations will be assessed later this spring when those fish move into the shallower water.  Determining population estimates for the fish in reservation lakes will be a big step forward in managing our resources.  Along with the fishery surveys, ESD is also collecting fish samples which will be analyzed for mercury.  Mercury in the environment is a concern and although we haven't had any issues with mercury in fish we are going to monitoring on a regular basis. 

A view from the front of the boat, the arrows indicate small fish in the electrical field

A juvenile walleye has a floy tag inserted into it's back

Fish and measured and weighed prior to tagging

Typically there are two netters on the front of the electrofishing boat

In the video below you can see small panfish as they hit the electrical field behind the probes.