Carp being removed at Nokomis

In July, Minneapolis Park & Recreation Board (MPRB) contractors began the process of removing carp from Lake Nokomis, using box nets that were tested at the site last fall.

This work is part of MPRB's Lake Nokomis Carp Management Research project, whose goal is to develop a long-term plan to manage invasive carp at Lake Nokomis.

Netting and removal of the carp occured during late-night and early-morning hours, due to the feeding schedule of carp. Corn bait was used, as it is eaten by very few fish other than carp; any sport fish or radio-tagged carp caught in the nets were returned to the lake.

During the removal, people might have seen an electro-fishing boat on the lake, or lights from flashlights and headlamps used on the boat and along the shore. Floats on the water marked box-net locations and ropes were used to tie off nets to shore. The carp removal continued through Thursday, July 25.

Carp removal is part of a three-year project to improve Lake Nokomis' water quality by reducing the lake's population of this invasive species. Research conducted during the project will also guide the development of an Integrated Pest Management plan for the carp.

As a bottom-feeding fish, carp root through lake-bottom sediments for food, decreasing water clarity and releasing excess phosphorus into the water. This increase in nutrients diminishes water quality by stimulating algal blooms. Carp also eat and uproot vegetation, which can destroy a lake’s aquatic plant community. Lakes with an overgrowth of carp typically have high phosphorus concentrations, low water clarity, and little to no aquatic plant growth.

The MPRB was awarded funding for a carp management research project in 2016. At that time, staff observations and preliminary estimates of the carp mass in Lake Nokomis, determined by electrofishing, indicated that the carp population had become excessive.