Tammy Newcomb, senior water policy advisor and fisheries research biologist
Photo credit: Michigan Department of Natural Resources
Partner’s Update – January 2014
Michigan DNR uses exercise to plan for Asian carp invasion
By: Tammy Newcomb, senior water policy advisor and fisheries research biologist
The Michigan Department of Natural Resources (DNR) has taken a strong stance on supporting measures to prevent the spread of Asian carp into the Great Lakes. However, without a separation between the Mississippi River and Great Lakes basins the risk of spread of these species and other AIS persists. Given this risk, if – or when – Asian carp make their way into Great Lakes waters; will the DNR be ready to deal with them? We certainly intend to be – so much so, that our Fisheries Division staged a two-day exercise on the St. Joseph River this past September to test our field skills and prepare the agency for action in the event silver or bighead carp show up.
The St. Joseph River was selected for the state’s exercise since it is the first major waterway up the Lake Michigan coastline from the Chicago Area Waterway System (CAWS). Many fisheries biologists believe Asian carp are likely to enter the Great Lakes, if they do, it's a coin flip whether they turn left or right as they head up Lake Michigan. The St. Joseph River has optimal habitat for Asian carp to spawn and potentially establish a population.
The two-day exercise involved 27 fisheries technicians and a handful of biologists. Using 14 boats our crews roped off a two-mile stretch of river several miles below the dam at Berrien Springs and strung nets across it to prevent fish from heading up or downstream during the exercise.
Field crews began the exercise by electro-fishing, collecting common carp, tagging them, and returning them to the water as part of a mark-and-recapture study to see how effective various techniques are at catching the fish.
During this exercise common carp served as surrogates for silver and bighead carp as they're roughly the same size and body shape and use similar habitats of the river. That gave us a known quantity of fish in that closed section of the river.
After the carp were tagged, the field crew deployed various configurations of large-mesh gillnets through the river to determine if electro-fishing efforts would chase silver and bighead carp into vertical walls of gillnet. On the second day of the exercise, we attempted to recapture those fish with only electro-fishing and then compared how effective the various techniques were at capturing the fish.
Overall the exercise went smoothly. The crew tagged many fish and recovered several of them over the next day. The first afternoon session included several thousand feet of gillnet set systematically so the effectiveness of the net sets could be evaluated. The following morning, the electro-fishing crews went back at it without the accompanying gillnets.
As a result, the Michigan DNR has confidence our strategies and field crews are ready to address the real deal -- live silver or bighead carp – if they show up in a Michigan stream.
This exercise was a necessary step in preparing for dealing with the risk of an introduction of Asian carp. The Michigan DNR will continue to work towards being prepared to make a prudent response if we get reports of bighead or silver carp in our waters.
DNR employees collect fish while electroshocking during the Early Detection and Prudent Response exercise on the St. Joseph River.
A DNR employee collects buoys used to track surveying efforts during the Early Detection and Prudent Response exercise on the St. Joseph River in Southwest Michigan.
All DNR employees that worked the Early Detection and Prudent Response exercise on the St. Joseph River pause for a moment to capture a group photo.
A DNR employee prepares to return a tagged sucker to the St. Joseph River as part of the Early Detection and Prudent Response exercise in September 2013.
Photos by Michigan Department of Natural Resources.