"Ships arriving in Chesapeake Bay ports bring more than just cargo — in 2013 they also inadvertently released an estimated 10 billion live zooplankton from other parts of the world, a finding that surprised the researchers who recently reported the results.
Regulations aimed at reducing the risk of aquatic invasions went into effect more than a decade ago, and a team from the Smithsonian Environmental Research Center had expected to see a decrease in live organisms being released from ballast holds of ships.
Instead, they found that concentrations of coastal zooplankton discharged into Bay waters had increased nearly fivefold from releases checked before the new regulations took effect in 2004.
'It wasn’t quite what we expected to see,' said Greg Ruiz, SERC senior marine biologist and a co-author of the study. 'We wanted to know how things had changed, and they changed in a way that we didn’t expect.'"