Department of Natural Resources scientists have identified unusually large algae blooms in sections of the Chesapeake Bay that could choke marine life this summer and create the largest oxygen-deprived "dead" zone on record.
Although scientists are unsure exactly what effect the blooms will have in the long term or how bad the summer "dead zone" could be, they said they have never seen dissolved-oxygen levels so low this early in the year since 1986.
The Chesapeake Bay Foundation went public with the findings at a news conference in Annapolis yesterday as part of a lobbying effort for the so-called "flush tax" that would raise funds to curb nutrient pollution from sewage plants.
"This is a precursor of a very severe dead zone, probably this summer," said foundation President William C. Baker.
If water conditions continue to decline, he said, the potential is there for a dead zone larger than last year's, which covered about 40 percent of the bay.
The consequences could be devastating for marine life.
On the other hand, the algae blooms - possibly a type of algae called heterocapsa that thrives in the winter and dies off as water temperatures warm - could dissipate and oxygen levels could improve, Baker said.
"Some scientists are calling this an exception," he said. "We don't want to say this is the end of the world ... but this is an indication that we could be in real trouble this summer."
Scientists are unclear exactly what is causing the large blooms, which can turn the water a mahogany color. Some speculate that the past year's heavy rains could be the culprit.
"It's possible that a lot of organic material washed into the bay [last year] and now it is just getting warm enough to cause this algae to bloom in greater number," said David Goshorn, chief of the living resource assessment program for the Maryland Department of Natural Resources. "But that's speculation at this point."
Goshorn said test results are not back on nutrient and algae samples and it could be several weeks before the cause of the algae blooms is determined. Still, he said, the results so far are worrisome.
"The bottom line is that in the main stem of the bay we are seeing near record-low and record-low levels of dissolved oxygen," he said. "Although the [dissolved-oxygen] levels are not low enough yet to cause stress or death to fish, the levels are low for this time of the year."
