Common carp management using biocontrol and toxins

Project manager: Przemek Bajer

Description: This project will test whether common carp can be baited and killed using corn pellets with antimycin-a, a natural fish toxin, without harming other species. Although other biocontrol strategies – such as using bluegills to consume carp eggs – are successful on some lakes, they are unsuccessful on lakes which are prone to winterkilling. Carp have a unique diet (plant seeds, such as corn, which native fish are not attracted to) and can be trained to aggregate in baited areas. Researchers will first determine the concentration of antimycin-a needed and the species-specificity of the approach.  They will then conduct trials to test this “bait and switch” concept with carp of different sizes in experimental ponds.  

This project will also test through whole-lake experiments whether bluegills can be used as a biocontrol agent for common carp. Researchers will conduct experiments on both moderately productive and very productive lakes, measuring carp and bluegill density over two seasons. Survival of carp eggs, larvae, and fry will be monitored at appropriate intervals throughout the study. Water quality and zooplankton abundance (food for larval carp) will be also measured as it might provide additional information about the survival of carp larvae and fry. Researchers will also analyze previously collected DNR data to evaluate whether aerating shallow lakes in the winter affects carp recruitment.

Project start date: 2015

Estimated project end date: 2017, Phase 2 to continue through 2019

Progress and updates:

Experimental ponds were selected in 2015. Common carp were stocked in all four ponds; bluegill sunfish were stocked in two of them. Carp spawning occurred in all ponds and several techniques were used to determine abundance and survival of eggs, larval fish, and fry in lakes both with and without bluegills.

Using data from the Minnesota DNR on lake characteristics such as depth, size, and productivity, along with winter aeration data, researchers will determine which lakes are capable of supporting bluegill populations high enough to control common carp.

In cases where biocontrol using bluegills is not an option, in 2016 researchers developed an antimycin-laced corn bait and are now evaluating its leaching rates and effectiveness.