The 2012 index for rockfish was 0.9, below the long-term average of 12 and dramatically lower than last year’s 34.58
Not since the state began surveying rockfish nearly 60 years ago has Maryland’s signature fish had its lowest rate of reproduction.Traditionally, low rainfall year (especially during spring) produce low Young of the Year Indices, and this has been no exception. Fish recruitment is a highly variable in any event, and substantial deviations from the long-term average are more the rule than the exception. This is not good news for bay sportsmen, however, as it suggests the 2012 year class will be all but absent. A few consecutive years of such recruitment failure could seriously impact the health of the population.
But biologists cautioned Tuesday that the fish is not in crisis — 2012’s low reproduction comes on the heels of a banner year in 2011. They’re attributing this year’s poor reproduction to unfavorable weather and the tendency of reproduction rates to fluctuate from year to year.
“It’s just the nature of the beast,” said Eric Durrell, a biologist with the state Department of Natural Resources.
The usual number of rockfish swam into the Chesapeake Bay this spring to spawn. But many of the eggs and larvae did not survive, possibly because of dry conditions or temperature changes, Durrell said.
Even a minor change in weather — a short cold snap, a rainy week — can be a death sentence for rockfish larvae.
“Larval survival is a delicate balance of the timing of the spawn, water conditions,” Durrell said. “You can have a wet year, but the rain comes at the wrong time … Your larvae can die pretty quickly.”
Another bit of evidence to suggest that the rockfish in the bay are in trouble, and unless care is taken in their management, another fishing moratorium may be in the work.