The Hopkins’ rose nudibranch gets its color from consuming a rose-colored encrusting bryozoan.
Climate change and warming ocean temperatures might have forced dolphins to change their range and destroyed corals. But they have proved beneficial to at least one species. Rising ocean temperatures off the coast of northern California have triggered a bloom in pink sea slugs. These inch-long sea slugs can now be seen in densities in dozens per square meter in tide pools along the central and northern California.
Rose sea slugs have a life span of one year
Scientists at the University of California San Diego, UC Santa Barbara, and the California Academy of Sciences said that the Hopkins Rose nudibranch (Okenia rosacea) is found off the southern California coast. Pink sea slugs are rarely seen in waters off northern California. Now they are concentrating in tide pools as far north as Humboldt County.
A bloom in rose sea slugs was predicted for the first time in 2011 by Stewart T. Schultz in a study published in the journal Limnology and Oceanography. The rose sea slugs grow rapidly and have a life span of only one year. Rare wind patterns have increased ocean temperatures along the West Coast in the past year, attracting warm water species like Hopkins Rose nudibranch.
Ocean temperatures were 5 degrees higher than normal
Scientists said that ocean temperatures off the West Coast were 5 degrees higher than normal last year.It’s not the El Nino weather, but the warming continues. Scientists said the temperature rise was caused by the absence of a normal process called upwelling. John Pearse, an evolutionary biology professor at UC Santa Cruz, said that they were initially worried the nudibranchs were being killed off.
Though the spread of pink sea slugs has added some exotic color to northern waters, it could be an ominous sign. Terry Gosliner of the California Academy of Sciences said that warming ocean means less food for sea birds, and it will have an adverse effect on all marine ecosystems. California’s marine life may not always adapt to such dramatic instability.
The Hopkins’ rose nudibranch gets its color from consuming a rose-colored encrusting bryozoan.
