BOSTON (AP) – The worst shellfishing season in decades may have a sequel this summer, thanks to recent record rains coupled with wind and water conditions similar to what fed last year’s ruinous red tide.

Early this week, rainwater runoff forced the state to shut down shellfish beds from the New Hampshire border to Cape Cod and Buzzards Bay. At the same time, the state enacted a red tide closure of shellfish beds from the New Hampshire border to Deer Island in Boston Harbor.

Scientists said Wednesday the recent weather has created conditions similar to what allowed last year’s red tide to spread.

“Whether it’s going to be … as big and lasting as last year, there’s no way to tell,” said Michael Hickey, the state’s chief shellfish biologist.

The toxic algae cells are absorbed by shellfish, making them hazardous and even deadly to eat. The 2005 red tide bloom closed the state’s shellfish beds for months during the peak spring and summer season and caused $50 million in losses to tourism and fishing industries.

“It’s very frustrating, but you know what it is, it’s part of a clammer’s life,” said John Grundstrom, a fifth generation shellfisherman from Rowley. “If you depend on it, you’re a fool.”

This month’s rains created runoff from flooded rivers, roads and overwhelmed sewer systems that carry waste and bacteria, which pollute shellfish beds, Hickey said. The swelled Merrimack River is dumping so much water into the ocean it’s probably affecting water quality down to Boston, he said.

The rain has caused similar problems in Maine, where flooding has forced the closure of clam flats from Cape Small in Phippsburg to the New Hampshire border.

“This could be a pollution problem for several weeks,” said Darcie Couture, director of biotoxin monitoring for the Department of Marine Resources. Red tide isn’t yet a big problem, she said, adding more testing will be conducted Friday.

It’s impossible to say how long the rain-caused closures could last, because the sources of pollution and remedies differ in different ecological areas. Hickey said the red tide closure may outlast any rain-caused shut downs, anyway.

Don Anderson, a red tide expert from the Woods Hole Oceanographic Institution in Falmouth, said the unique conditions that fed the wild spread of last year’s red tide have recurred.

First, in the central part of the Gulf of Maine there’s an abundance of the red tide cysts that bloom into the toxic cells – Anderson put the amount at about five times the number measured in 1997. That’s about half the amount measured before the 2005 bloom, but still enough to cause a problem, Anderson said.

Second, recent rains have poured fresh water into the ocean. Fresh water has nutrients that the red tide cells feed on. The cells also live in the brackish surface layer that forms, moving more quickly and broadly with the winds.

Third, this month’s winds, including during the recent deluge, came from the northeast and pushed the red tide cells toward the shore, where they feed on nutrients. Winds are generally out of the southwest in May.

“All the pieces are in place, as they were last year,” Anderson said. “But at the same time, there’s plenty of opportunity and plenty of chance for this to go by and go away.”

The winds that came with the rain were favorable for the red tide, but the cloudy, cool weather wasn’t and might have hindered its growth, Anderson said. The organisms that eat the cells may well be more abundant this year and curb any red tide growth, he said.

And if Wednesday’s southwest winds persist, the red tide cells could be blown out to sea.

Ronald Bergstrom, a shellfisherman for 30 years from Chatham, said any closures are a major concern in a town where 500 of its 6,600 residents have shellfishing licenses. At the same time, he said, it’s a day-to-day business, and the red tide or rain closures have yet to affect fishermen that far out on the Cape.

“They can’t worry about what might happen,” Bergstrom said. “They’re attitude is they’re going to (fish) until someone tells them to stop.”

AP-ES-05-17-06 1726EDT