Investigating Extent and Impacts of Cochlodinium bloom in Chesapeake Bay and Tributaries
In September 2007, the Harmful Algal Bloom (HAB) Event Response Program provided emergency funds to scientists from Old Dominion University and Stony Brook University to sample the extent and investigate fishery impacts of a bloom caused by the dinoflagellate Cochlodinium polykrikoides occurring in the Chesapeake Bay and some of its tributaries. The bloom, which likely originated in the Elizabeth River and then spread into other rivers and the bay, was associated with fish kills and caused beach closures, extensive media coverage, and public alarm in Virginia. There was also concern that the bloom could interfere with ongoing oyster spat planting activities in the region. Initial toxicity tests showed rapid larval fish mortality when exposed to bloom samples, and similar tests with oyster spat showed 20 percent mortality in 48 hours. The researchers coordinated with other responders throughout the region, such as those conducting aerial overflights of the bloom, to maximize sampling efficiency. These data aided mitigation of the event as it was occurring, and the knowledge gained will improve management capabilities for future events.