Wednesday, July 28

Goldfish dumped into lakes grow to monstrous size and threaten ecosystems | Invasive species


Minnesota authorities have called on aquarium owners to stop releasing pet fish into waterways after several huge goldfish were pulled from a local lake.

Authorities in Burnsville, about 15 miles south of Minneapolis, said released goldfish can grow several times their normal size and wreak havoc on native species.

“Please don’t release your goldfish in ponds and lakes!” the city tweeted on Friday. “They grow larger than you think and contribute to poor water quality because they remove sediment from the bottom and uproot the plants.”

Last November, officials in the vicinity Carver County removed up to 50,000 goldfish from local waters. The county’s water management manager, Paul Moline, said goldfish “are a poorly studied species” with “high potential to negatively affect lake water quality.”

Like carp, goldfish can easily reproduce and survive through low oxygen levels during the Minnesota winter.

“Some goldfish may seem like a harmless addition to the local body of water to some, but they are not,” says the Minnesota Department of Natural Resources. advised.

The ecological destruction caused by released aquarium pets is not new. The carnivorous lionfish, native to the Indo-Pacific but believed to have been released by Florida pet owners after Hurricane Andrew in 1982, has killed dozens of Caribbean species, allowing algae to take over reefs.

Goldfish have received less attention than other invasive species, including Asian carp and zebra mussel, but warnings have been issued in Virginia Y State of washington as well as Australia Y Canada.

In 2013, American scientist reported that Lake Tahoe trawler researchers caught a goldfish that was nearly 1.5 feet long and weighed 4.2 pounds. The author of a report on the California aquarium trade said: “Globally, the aquarium trade has contributed one-third of the worst aquatic and invasive species in the world.”

Wildlife officials in Virginia recently warned that “pet owners should never release their aquatic organisms into the wild” after a fisherman catches a 16 inches goldfish.

The costs of rehabilitating goldfish-infested waterways are substantial. Carver County in Minnesota signed an $ 88,000 contract with a consultant to study how to eradicate shoals.

The Washington Post reported that in 2018 Washington state officials said they would spend $ 150,000 rehabilitating a lake near Spokane. In Alberta, Canada, an invasive species expert call a “scary” goldfish problem.

It is estimated that up to 200 million goldfish are raised each year, the majority ending up in domestic display.




www.theguardian.com

Leave a Reply

Your email address will not be published. Required fields are marked *