Above are images of a species of turtle, an aquatic aquarium plant, an everyday goldfish (photo courtesy of Buffalo Niagara Waterkeeper) that were, and continue to be, released into the wild. These species are now considered invasive and have become serious environmental threats to the waterbodies they inhabit. Sadly, all of these careless releases and the damage they have caused could easily have been avoided.
The first is a red-eared slider. This invasive freshwater turtle now has a place on the world's top 100 worst invasive species list. Even though it is native to the Mississippi River Basin, it becomes a nuisance outside of its home range. It is now found in ponds, lakes, rivers, streams and manmade ditches in many states where it outcompetes native turtles for food, nesting habitat and basking sites. This invasion could have been avoided if pet owners had donated their unwanted sliders to someone willing to take care of them or surrendered them to the pet store where they were originally purchased. Unfortunately, red-eared slider sales surged because of a trend (which is never a good thing, think bunnies at Easter) when they became a must-have pet in the 80s and 90s due to the popular Teenage Mutant Ninja Turtle Franchise. The original comic book turtles were all red-eared sliders. This led to many purchases and subsequently many releases of these turtles.
The second is Brazilian elodea, a familiar plant purchased for many aquariums because it is considered a good oxygenator. In its native home of Brazil, this plant grows normally since it is obviously kept in check, however, when dumped into a lake or pond in North America, it becomes incredibly invasive. Just a single, small fragment can form a new plant and ultimately take over an entire waterbody. It can outcompete local species and form dense mats, as seen above, making it impossible for other plant species to grow and difficult for fish to find food. Brazilian elodea is spread between waterbodies mainly by boat propellers and fishing gear. Never flush plants down the toilet, as they can be released via city sewer systems, always compost them far from a waterbody.
The third is a typical goldfish from east Asia that you buy at a pet store or win at a carnival. When kept in a tank, goldfish, which are part of the carp family, will usually stay around two inches long. When released into the wild they can grow up to 15 inches since they are typically limited by their container size and quality of water they are living in. Ponds and lakes are very big containers with better water quality than a non oxygenated fishbowl. Most recently, a 14 inch goldfish was reported in the Niagara River and posted by Niagara Waterkeeper. Flushing a two inch goldfish may seem harmless, but if you live in an area with a public sewer then you run the risk of causing serious environmental damage by releasing that fish. When Gill from Finding Nemo said, "All drains lead to the ocean, kid," he wasn't too far off!
Goldfish, and other non native aquarium fish, outcompete native species, displacing them and removing vital food sources for other animals in a waterbody. They breed quickly and are very difficult to manage once established. Scientists are now estimating that there are tens of millions of goldfish in the Great Lakes.
Goldfish will be included in the next update of Lakes SOS.
Please help preserve our natural communities by surrendering your fish or turtle to a pet store and composting any unwanted aquarium plants.