Climate Change Helping Tropical Fish to Destroy Kelp Forests of Japan, Australia

Climate change is helping tropical fish move to temperate zones, a new study has found.

According to researchers, this global warming-led fish migration is threatening the survival of kelp forests and algae in sub-tropical and temperate regions of the world, abc news reported.

Researchers at the University of New South Wales, who were involved in the study, warn that tropicalization or the movement of species from tropics to poles might affect the local ecosystem.

"The tropicalisation of temperate marine areas is a new phenomenon of global significance that has arisen because of climate change," said study lead author, Dr Adriana Verges, of UNSW Australia.

Under ideal conditions, kelp forests can grow up to 18 inches a day. These large, underwater forests with towering canopies provide food and shelter to thousands of marine organisms.

The study shows fish species such as rabbitfish have damaged large kelp forests in Japan. Loss of kelp and algae in the region has affected local abalone fisheries, according to abc news. Researchers said that over 40 percent of kelp and algae beds have disappeared since the 1990s.

Kelp forests of Western Australia were damaged by a heat wave that occurred in 2011. Verges and colleagues suggest that tropical fish are preventing these forests from recovering. Intense grazing by these fish has reduced the area covered by kelp in Eastern Australia.

In the tropical regions, plant-eating fish help keep the coral reefs free of seaweed. In fact, United Nations Environment Program and others stated in a recent report that parrotfish need to be saved to protect coral reefs in the Caribbean.

These helpful weed-clearing fish, however, pose great danger to local marine life when they invade temperate territories.

"Increases in the number of plant-eating tropical fish can profoundly alter ecosystems and lead to barren reefs, affecting the biodiversity of these regions, with significant economic and management impacts," Verges added in a news release.

The study is published in the journal Proceedings of the Royal Society B.