PRINCESS ANNE -- Tony Mazzaccaro last week peered through a microscope lens, searching for an elusive killer. "I just don't see it," he said. "Looks like I won't have to nuke the pond after all."
This time.
Mazzaccaro, owner of the Hyrock fish farm by the Manokin River in Somerset County, was looking for a microorganism that might have been responsible for killing 8,000 of his hybrid striped bass in early August. A year earlier, a microbe may have killed 23,000 of his farm's adult bass.
Both times, he had to "nuke" several of his fish ponds -- treat them with chemicals to clean them of harmful organisms.
Mazzaccaro's ponds are filled with water from Goose Creek, at the mouth of the Manokin River in Somerset County.
The state closed portions of, the Pocomoke River in Somerset County and the Chicamacomico River in Dorchester County, along with Kings Creek, a Manokin tributary, this summer after fish and people were apparently sickened by a sometimes-toxic microorganism, Pfiesteria piscicida.
After the August fish kill at Hyrock, water tests were inconclusive as to whether it was the work of Pfiesteria. Experts say that kill likely was the work of another harmful microbe.
But after the 1996 incident, Pfiesteria was found in Mazzaccaro's ponds. Experts still differ on whether that microbe or another one killed his fish at that time.
Now Pfiesteria and other harmful microorganisms may be casting a broader shadow over the aquaculture industry, which has been considered a growing and bright business in Maryland.
Nationwide, aquaculture is a billion-dollar industry. In Maryland, it has been hot -- growing from nearly nothing 10 years ago to $20 million in sales last year.
Maryland officials have been aggressively promoting aquaculture because the state has a favorable climate, location and, most important, abundant water resources, said Roy Castle, chief of the aquaculture program for the state Department of Agriculture.
"There's just a tremendous market for it," Castle said. "The state's located within eight hours of one-third of the country's population. And they eat a lot of seafood."
But Pfiesteria now has thrown some in the industry for a loop.
"With the Pfiesteria scare, the seafood market has dropped in half," said Richard Pelz, of St. Mary's County, president of the Maryland Aquaculture Association.
