Corals gain climate-change shield

Rare species of staghorn corals may bear some good news for reef conservation: It appears that some rare types of staghorns can readily breed with related species, creating hybrids that may be far more resilient to climate change or other stresses than anyone thought.

That’s the word from a team of coral researchers at James Cook University and the Australian Research Council’s Center of Excellence for Coral Reef Studies in Townsville, Queensland.

Reefs worldwide are under pressure from human fishing practices, pollution, climate change, and ocean acidification. Rare species, which often live in smaller colonies than other, more-common corals are thought to be among the most vulnerable.

The team studied the genetic makeup of 14 rare and eight common species of staghorns, the leading reef-builders in the Indian and Pacific Oceans.

To their surprise, they found that some of the rare species are hybrids that had cross-bred with other staghorn species, and still retained their ability to reproduce fertile offspring.

In principle, these hybrids may be better able to adapt to changing conditions, the team says, because they display a higher degree of genetic diversity than the blue-bloods of their species.

“This is good news, to the extent that it suggests that corals may have evolved genetic strategies for survival in unusual niches,” notes Zoe Richards, who led the effort.

The results appeared recently in the online journal PLOS One.