Rock Pond on the campus of the University of Minnesota Duluth (UMD) is filled with hundreds of goldfish. While not as nasty as the snakehead fish found in some Maryland ponds, goldfish are just as illegal to release into local waterways. The problem is that the two-acre pond drains into Tischer Creek, a designated trout stream, which flows into Lake Superior.
"Unfortunately, Rock Pond appears to be the local dump for unwanted fish by aquarium or water garden owners," said Doug Jensen, Aquatic Invasive Species Information Center coordinator for the University of Minnesota Sea Grant Program. "The goldfish indicate that aquarium releases are going on, and more dangerous species could get into local waters unless we make people aware of the issue," said Jensen. "Fortunately, there's a remedy for the Rock Pond situation because it's a constructed pond with an outflow that needs rebuilding. If similar releases occurred in other area lakes or rivers, attempts to eradicate or control the spread would be extremely costly."
To eradicate the goldfish, koi and rusty crayfish, Rock Pond is being pumped dry this week. Fish remaining after the drawdown will be collected for composting. A group worked for a year considering alternatives to this method and how to address possible downstream effects of the pond draining. They investigated giving the fish away or having a local pet store sell them, but ran up against prohibitive regulations.
The effort is costing UMD $50,000, not including the staff time from eight departments and cooperating agencies. The pond should refill naturally from runoff and rain later in the season. Public awareness of this issue is being communicated to student residents by e-mail, fliers posted in the resident halls and signs near the pond before the students leave the dorms for the summer.
"Instead of releasing your plants, fish, and other animals, you can give them to another aquarium owner, advertise to give them away, or donate them to a public facility, nursing home or business that has an aquarium or water garden," said Jensen.
Rock Pond is serving as the testing ground for a national campaign led by Sea Grant, the U.S. Fish and Wildlife Service and the Pet Industry Joint Advisory Council. The project seeks to prevent the release of aquarium and water garden fish and plants through an educational campaign that involves large aquarium fish retailers such as PetCo, Wal-Mart and many private outlets.
The group is finalizing a logo and slogan that will be seen on the bags in which hobbyists carry their fish home, static stickers on new fish tanks, brochures, a Web site and hobby magazine ads. The informational signs used in the Rock Pond project will serve as templates for similar situations across the country.
From snakeheads to giant salvinia, over 38 species of unwanted fish and dozens of plants, crayfish and snails have been accidentally released into fresh and marine waters of the United States by aquarium and water garden owners. Releases of potentially invasive species can impact the economy, recreation and the environment. They can cause impaired water quality, clogged waterways, competition and hybridization with native species and diseases. While environmental and economic consequences for most species are unknown, impacts of some infestations have cost millions of dollars for control and management.
New sightings of exotic species should be reported to Minnesota Sea Grant at (218) 726-8712, the Minnesota Department of Natural Resources (DNR) at 1-888-MINNDNR or (651) 296-2835, or a local DNR fishery office.
Marie Zhuikov is communications coordinator for the University of Minnesota Duluth's Sea Grant Program.