Goldfish are becoming an invasive species that have negatively affected lakes within the USA, in addition to around the world. Large goldfish are found in lakes within America such as Lake Tahoe, Quemado Lake in New Mexico, and Lake St. Clair in Michigan. Experts are worried how quickly goldfish can breed and alter an ecosystem.
Goldfish dumping is happening around the country. They are common in household aquariums and garden pools. They can easily be obtained, usually being among the cheapest fish to purchase. In addition to that, they may be brought home through other means, for instance, people can win a goldfish out of a game booth at a fair. When the goldfish is no longer wanted, or maybe on account of the need to move, people may believe that they are being kind to their pet goldfish by setting it free in a nearby lake, as opposed to killing it. But while they may save their pet’s life, the goldfish may destroy a whole population of native fish.
According to a specialist, Sue Williams, who’s an ecology professor at the University of California, aquarium dumping has generated one third of the world’s worst aquatic invasive species. Aquarium fish could become an invasive species and goldfish, of all species, do some of the worst invasive damage.
Goldfish create waste, which feeds algae near the coast. Their feeding habits not only reduce water clarity, they can also ultimately cause a drop in water oxygen. This in turn increases water temperatures, which then destroys the natural habitat for young, juvenile fish. Goldfish root around in the mud, making the waters murky and suspends sediment.
Goldfish have been in Lake Tahoe since the 1990’s. Because Lake Tahoe is a huge tourist attraction for boating, hiking, cycling, and swimming, biologists have been employed in an effort to maintain the waters pristine. They found that goldfish are becoming an invasive species. In 2011, Melbourne Wildlife Control found a 14.2 inch goldfish weighing over three pounds.
Not only are goldfish a problem to Lake Tahoe, but also pollution and climate change have become problems to the Lake Tahoe ecosystem. Thus, with all the challenges to Lake Tahoe, goldfish can be a factor that may tip the balance to an entirely different type of lake composition. In 2011, Nevada passed a law making it illegal to dump goldfish and other invasive fish.
As already mentioned, another lake invaded by goldfish is Quemado Lake in New Mexico. More than five and a half tons of goldfish have been removed from this lake. There were numerous goldfish, it gave the lake an orange hue.
One way to remove the invasive fish is to shock them, which stuns the fish and allows them to be gathered and removed. Few fish really die from electrical shock.
One third of the worst invasive aquatic species of the world has come from the practice of dumping aquarium goldfish and other anti inflammatory fish. Like the pythons who have invaded the Florida Keys, and have become a significant problem that’s eating natural species and affecting the natural habitat, goldfish are turned into a serious invasive problem because of aquarium owners who are dumping unwanted fish, not realizing the serious consequences of their actions.