Characteristics of the Invasive Species
The goldfish is an animal of the fish species that lives in fresh water. This animal is most widely used as an ornamental fish in aquariums for homes. It is important to emphasize that the species itself did not exist, but was artificially bred as a result of the domestication of its ancient ancestors (Roos, 2019). The genetic background of the fish is characterized by several mutations that allow asserting that this species is dangerous for wildlife. Such an animal is distinguished by omnivorousness, endurance, increased activity and the ability to reach huge sizes (Roos, 2019). Another name for goldfish is Chinese crucian, and in Latin – Carassius auratus (Roos, 2019). At the moment, the species can be called invasive, since in some states of the USA, in Australia and Latin America, goldfish have leaked into wild waters.
Place, Date and Reasons of Invasion
Large goldfish were caught in Lake Keller, Minnesota. This was announced on July 9, 2021 by the authorities of the city of Burnsville on their Twitter (Helmore, 2021). The State Fish and Wildlife Service has asked goldfish owners not to throw their pets into local waters (Helmore, 2021). The agency warned that the fish not only grow large, but crowd out other inhabitants of the lakes and destroy the natural ecosystem (Roos, 2019). The study of the local population of abandoned goldfish began after complaints from local residents about possible contamination of the water in the lake (Roos, 2019). It turned out that it was domestic fish that caused the deterioration in water quality. In turn, they appeared in the wild due to the irresponsible draining of them by people into sewers and reservoirs. The fisheries service also said that throwing aquarium fish into water bodies is punishable by law (Roos, 2019). They can be carriers of deadly diseases for species in their natural habitat.
Environmental Impact
Goldfish have an extremely negative impact on the environment, primarily due to their increased activity. They interact with the silt and the bottom of the reservoir, as well as the roots of aquatic plants and algae. This leads to massive pollution of water bodies, as well as a violation of natural barriers in the form of grass (Heck, 2017). In addition, goldfish are omnivores, which poses a threat to the biological chain. Together with the large size they can reach, fish claim to be the largest predators and herbivores. The lack of control of such a situation can lead to the extinction of both one reservoir and the nature of the state as a whole (Heck, 2017). Earlier, a fisherman from Virginia caught a goldfish of record size – more than 40 centimeters in length and weighing 1.6 kilograms (Helmore, 2021). The Washington Post reports that a total of 28 rugby-ball-sized fish weighing more than a kilogram have been caught in Lake Keller (Helmore, 2021). This fact demonstrates that this invasive species is extremely voracious.
Propagation Speed
There is another factor threatening wildlife, namely the rate of reproduction of goldfish. At home, the situation is under control, so there is no rapid population growth. However, in wild waters there are favorable conditions, in the form of excess food, comfortable temperature and lack of competition (Helmore, 2021). This allows goldfish to multiply extremely quickly; in a year, the population of the species in lakes increases by one and a half times. This leads to very rapid deterioration of the water and the extinction of the weaker due to suppression. Combined with the large size that goldfish can reach, this is deadly for an entire region of water bodies and the local ecosystem (Helmore, 2021). For example, in Minnesota, about 50,000 gold slaves were found in one reservoir, despite the fact that only a few pairs were disposed of by people (Heck, 2017). This statistic suggests that the rate of propagation is extremely high.
Identification
A facilitating factor is that the invasive animal has striking features by which it can be easily identified. Firstly, the fish has a characteristic golden or orange color, which creates reflections in the sun and is very cloudy in the water (Heck, 2017). Secondly, the fish kicks the carp strongly on the structure of the body, which is associated with its ancient ancestors. Finally, the species reaches a large size, which makes it conspicuous in water bodies (Heck, 2017). It is important to note that these animals are able to exist only in fresh waters, as well as in areas close to human civilization.
Control Methods
In order to prevent a biological catastrophe, the state authorities made changes to the local legislation. In particular, this concerns the fact that people have a direct responsibility before the law for throwing away goldfish. In addition, when a reservoir is found infested with an invasive species, measures are taken to release it (Roos, 2019). They include fishing aimed at catching a specific species, introducing a limited number of predators. Finally, society struggles not only with the consequences, but with the prerequisites. The initial price of fish in pet stores is increasing, the requirements for owners are increasing (Heck, 2017). The combination of the above measures does not yet allow coping with the entire problem, but controls it at the same level, preventing progression.
Potential Hazard
It must be emphasized that goldfish are indeed dangerous to nature, and this is quickly becoming relevant. First, the admission of a species to the wild leads to the extinction of plants. This destroys the natural barrier to weeds and insects, causes lakes to bloom and degrades water quality (Roos, 2019). Secondly, goldfish dig the bottom, picking up silt and small crustaceans (Roos, 2019). This leads to violations of the self-purification cycle of water bodies, which means the extinction of animals in them (Roos, 2019). In turn, the destruction of the living world introduces a serious ecological imbalance, which can cause, for example, desertification of territories.
Conclusion
As a conclusion, it must be emphasized that humans are responsible for the emergence of invasive species in the wild. Ignoring or not realizing potential threats, a serious danger is created for the environment and the environment. Using the example of the situation with goldfish, it was considered that negligence and irresponsibility can lead to negative consequences. Even though the particular example is under control, experience shows that a catastrophe is possible.
References
Heck, C. (2017). Super-sized goldfish pose giant problem for lake Tahoe. U. S. Department of Agriculture. Web.
Helmore, E. (2021). Goldfish dumped in lakes growing to more than 1ft, threatening ecosystems. The Guardian. Web.
Roos, A. M. (2019). Goldfish. Reaktion Books.