BROWN TIDE FOUND IN DELAWARE'S INLAND BAYS

Delaware's Inland Bays already have two harmful algal species, Pfiesteria and red-tide dinoflagellates. Now a third harmful algal species, Aureococcus anaphagefferens, that causes brown tide, has been identified in the Inland Bays.

David Hutchins, a Delaware Sea Grant researcher, and Bruce Richards, director of the Center for the Inland Bays, collected samples this winter and found brown tide in Little Assawoman Bay, and even higher levels in Assawoman Bay in Ocean City, Maryland. Because the two are connected, it is possible that Assawoman Bay is the source of brown tide found in Little Assawoman Bay. In June 1998 surface water was collected from 13 sites, including Indian Rivers, Rehoboth, and Little Assawoman bays.

"The brown-tide organism was definitely already present in Little Assawoman Bay. No brown tide cells were observed in eleven samples from Indian River and Rehoboth bays," Hutchins states. Brown tide kills by rapid growth that can disrupt entire estuarine communities. "Laboratory studies are currently being conducted with cultured brown tide growing in water collected from several sites in the Inland Bays. We hope to be able to give managers some idea of the potential for harmful algal blooms in the bays, and the conditions under which they are likely to happen," Hutchins says. Further information from: dahutch@udel.edu.

OCEANSP@CE Issue 125. Monday 29 March 1999