ANNAPOLIS — ANNAPOLIS -- The Chesapeake Bay's rockfish, which have been under tight fishing limits to protect the once-threatened species, have bounced back after two poor years of reproduction, state natural resources officials said yesterday.
"The rockfish are back, and I think back to stay, as long as we manage them carefully," said Dr. Torrey C. Brown, Maryland's natural resources secretary.
The source of Dr. Brown's optimism was the state's annual sampling of four major spawning areas for striped bass, known around the Bay as rockfish. Biologists netted an above-average number of tiny rockfish that had hatched last spring.
The "young of the year" survey, in which state biologists sample the same 22 places around the bay three times during the summer, yielded an average of 9.1 baby rockfish per haul of the 100-foot seine they used.
That was only a little above the long-term average of 8.6 fish for all previous surveys dating back to 1954, when the state first began compiling figures.
But with the exception of 1989, this was the best year for baby rockfish in nearly 20 years, and it was good news for Maryland officials, who had been criticized by some conservationists for relaxing a five-year fishing moratorium too soon.
Poor reproduction and plummeting commercial harvests in the 1970s and 1980s led Maryland to impose the moratorium in 1985, and other East Coast states followed with catch restrictions to protect the dwindling fish.
Striped bass spawn in estuaries like the Chesapeake, but then migrate to the Atlantic Ocean and roam from Maine to North Carolina.
A near-record number of young striped bass found in the 1989 survey prompted Maryland to relax the moratorium three years ago and to allow limited fishing. But reproduction was poor in 1990 and last year.
This year, a bumper crop in the Potomac River lifted the state's index, with 22.1 juveniles found in each haul of the seine. The Nanticoke River also yielded more than it has in a decade.
Reproduction was off again in the Choptank River, where it has been strong in two of the last four years. In the upper bay, traditionally the leading rockfish spawning ground, young rockfish survival remained poor for the third straight year.
Officials said they had no explanation for the poor results. There were plenty of mature female rockfish in the upper bay and in the Choptank this spring, they noted, but the newly hatched larvae must not have survived.
Weather and water quality influence spawning and survival of rockfish. If water temperatures dip below 55, fish eggs die. Acid rain and toxic metals in the water also may kill larvae.
"It would be nice if we could get all of these rivers going real good," said Donald Cosden, the DNR biologist in charge of sampling juvenile rockfish.
W. Peter Jensen, DNR's fisheries director, said there are other indicators that the bay's rockfish population "is in really great shape this year."
More rockfish are turning up in rivers not included in the survey, such as the Chester, Magothy, Patuxent and Severn.
Other East Coast states also reported above-average reproduction levels this year.
It will be three years before the fish spawned this year reach legally catchable size.
But the decent reproduction levels mean there should be some "stability" in the quota of rockfish that Maryland fishermen can take, Mr. Jensen said.
Maryland fishermen this year may catch up to 1.6 million pounds of rockfish, with the harvest divided among recreational anglers, charter boat fishermen and watermen. Recreational rockfish season begins Oct. 1, with each fisherman allowed to keep one fish between 18 and 36 inches long per day.