August 20, 2012
Atlantic Ocean Gets Hit With Invasive Brittle Star Species
redOrbit Staff & Wire Reports - Your Universe Online
The appearance and ecology of Atlantic coral reef habitats could be altered by yellow brittle star
A study co-written by Dr. Gordon Hendler of the Natural History Museum of Los Angeles County (NHM) about an invasive species of brittle star, Ophiothela mirabilis, has been published online in Coral Reefs, the Journal of the International Society for Reef Studies. Growing populations have established themselves at distant points in the Atlantic although the species was previously restricted to Pacific waters. Its presence near Caribbean and Brazilian ports indicates that it may have been spread by shipping.
This marine animal is colorful and six-rayed. It clings to corals and sponges in multitudes and reproduces asexually, by splitting in two and redeveloping severed body structures. The species capacity to reproduce and scatter increases enormously due to the ability of one star to "clone" huge numbers of identical twins.
The impact of the ophiothela brittle star remains to be seen. It is hard to see how it will affect the ecology of its new ocean, as with most marine invertebrates, we know little about its biology. Multitudes of Ophiothelas densely colonize gorgonians and sponges on Indo-West central Pacific and on tropical eastern Pacific reefs so further expansion of the range of Ophiothela could alter the appearance and the ecology of Atlantic coral reef habitats.
"I imagine that when my grandchildren learn to scuba dive," Hendler says, "Caribbean reefs will look very different than they do today, in part because many corals and sponges may be covered with a network of invasive yellow brittle stars."
Invasive species have a massive impact on our economy and our environment. Every year they cause over 100 billion dollars of damage in the U.S. alone. Invasive echinoderm species are exceptional (invasive plants and insects are much more numerous). The Japanese sea star (Asterias amurensis) that was native to the north Pacific is probably the best known. It now damages fisheries in Tasmania and southern Australia. Notably, it is among the species that recently washed ashore in Oregon on Japanese Tsunami debris.