In recent years, the presence de peces Giants in different ecosystems has generated both concern as a fascination among experts and citizens. The size that some species reach, whether endangered native species or expanding invasive species, highlights the fragility of aquatic ecosystems and the importance of collective action to protect them.
While certain regions of Europe still boast of hosting iconic giant species under threat, other places face the troublesome de peces foreign that have grown out of control, with serious consequences for local biodiversity. In this article, we review two opposing realities: the resilience of a native fish in Andalusia and the invasion de peces large dorados in American lakes.
Giant goldfish: Surprising invaders disrupting US lakes
In the United States, the Fish and Wildlife Service has sounded the alarm over the proliferation of giant goldfish -up to almost two kilos- in lakes and ponds. many owners, believing that releasing them is an ethical alternative to keeping them in fish tanks, they dump them into natural environments without considering the environmental impact that they provoke. These fish, domesticated for over a millennium in Asia, reproduce easily and display extremely voracious behavior.
The detected specimens In places like the Great Lakes, they have even been nicknamed "megalodons" due to their disproportionate size. Their diet includes eggs and larvae of native species, which directly impacts the survival of native fauna. In addition, they stir up sediment as they feed, clouding the water, promoting algae growth, and reducing oxygen levels in the environment, which can cause mortality among other species.
The problem is aggravated by the absence of sufficiently large predators to control these populations and for their resistance to adverse conditions, such as heat or oxygen shortage. This translates into an almost unstoppable ability to colonize new habitats. and multiply in a short time; there have been cases where, after eliminating thousands of individuals, the population grows again in just one year. It has also been observed that their presence can promote the appearance of toxic bacteria, such as cyanobacteria, which represents an added risk to environmental health of the lakes.
Therefore, authorities insist on the importance of not releasing domestic fish into the wild and of choosing responsible alternatives when it is necessary to dispose of them. expansion of giant goldfish It is already a recognized threat in large areas of North America.
The giant guitarfish: a native species on the brink of extinction that is resisting in Andalusia
Faced with the advance of the invaders, Europe continues to fight for preserve large native speciesand giant guitarfish -or guitar, Glaucostegus cemiculus- This animal, related to rays and sharks, is one of the most unique inhabitants of the Andalusian coast, especially in Cádiz and Huelva, which represent the last European refuge where a stable population still exists.
Today Giant guitarfish is listed as critically endangered by the International Union for Conservation of Nature (IUCN). This situation is the result of overfishing, habitat destruction, and human pressure on the coast. However, thanks to the collaboration of scientists, associations, and citizen involvement, the species is managing to survive, although its future remains uncertain.
The protection of this giant Andalusian fish highlights the importance of conserving native biodiversity and promote conscious coexistence with marine ecosystemsActions such as scientific monitoring, catch reduction, and environmental education are key to halting their disappearance.
The growing presence of giant fish, both invasive and native, reflects the need for collective action to ensure the balance of aquatic ecosystems and protect the natural wealth we still retain. Stories of invasion and resistance demonstrate that, in the face of environmental risks, responsibility and citizen participation are essential tools for making a difference.
