For the first time, a sea sponge was found off the coast of New Zealand, and like coral bleaching, it lost its color, most likely due to unusually high temperatures in the ocean.
Researchers at Victoria University of Wellington found bleached sea sponges on the southern coast of the South Island during an expedition in April, which are usually chocolate brown, Britain’s Guardian news portal reports.
In some places, 95 percent of sea sponges have been bleached
said the university’s marine biologist, James Bell.
Based on the first data, researchers believe that hundreds of thousands of sea sponges may have vanished. The water depths around the archipelago are inhabited by colonies of sea sponges that provide a home for fish and release carbon that other species use as food.
There have been reports of intermittent sponge bleaching for some time now, such as along the coast of Tasmania in Australia, but sea sponges are usually more tolerant of changes in the ocean than other species such as corals. James James said that this is a completely unusual phenomenon.
According to the scientist, bleaching with a sponge “highlights the climate crisis facing humanity.” “There are a lot of species around New Zealand and we have no idea how heat-tolerant they are,” he added.
The world’s sea temperature broke a record last year, and the area around New Zealand, where coastal waters were 2.6 degrees warmer than average in April of this year, was no exception. Among the areas hardest hit by sponge bleaching, the sea off the coast of Fiordland is above average, with temperatures five degrees above normal, the strongest sea heat wave in forty years.
According to James Bell, more research is needed to clarify that the bleaching is caused by a warming ocean. So far, researchers have only observed a “very strong relationship” between bleaching and a sharp rise in temperature.
According to the scientist, some bleached sponges may appear, but whether this will happen can only be revealed by further observations.
