Yellow perch fishing is a rite of late winter and early spring in Maryland, when anglers work the tidal tributaries, hoping to find the spawning runs near peak levels.
In some rivers, it is hard enough to find yellow perch, much less catch more than two or three of legal size. But the yellow perch continues to be a special species to good numbers of fishermen.
"Yellow perch are so regional that you get some people fishing for yellow perch who may not fish much for anything else the rest of the year," said Harley Speirs of the Department of Natural Resources Tidewater Fisheries.
But the yellow perch is something of a puzzle, too, a relatively slow growing, small fish that lives its life- span in one river system and adapts its life cycle to the conditions of a given tributary.
Speirs said that the differences among river systems also makes it hard to manage tidal yellow perch statewide.
"Yellow perch are tributary specific and there are different growth rates in different rivers," Speirs said. "The rate in the Choptank, for example, is different from that in the Chester."
Yellow perch can live up to 13 years, Speirs said, and males generally reach sexual maturity beginning at age 2. Females may begin spawning at age 3 and virtually all spawn by age 5.
"Depending on the river system," Speirs said, "the males will be 6 inches and up at sexual maturity, and females will be 7 to 10 inches."
A few years ago, the DNR discontinued a stocking program for yellow perch and now relies on fishing regulations to protect and expand populations, setting minimum size limits so that in a given tributary each year class should have at least one chance to spawn before it can be taken out of the population.
Size limits range from 8.5 inches, to 10 inches, depending on the tributary, Speirs said.
"If overfishing was the core of the problem," Speirs said, "then regulations should allow correction of the problem. But if, for example, habitat is the controlling influence, then regulations won't correct it."
In the Severn River, one of several Western Shore tributaries in which keeping yellow perch of any size is prohibited, there is some evidence that stocking and closure have helped the yellow perch population, Speirs said.
"For example, one fisherman who called us said that he had found a [catch and release] honey hole for yellow perch on the Severn," Speirs said. "The location he gave us turned out to be one of the last places we stocked, so we know that the program is working there.
"It is the same way on the Wye River, where people again are catching yellow perch below the dam."
In other rivers as well, the yellow perch is mounting something of a comeback, but Speirs said it is hard to quantify because researchers might have "to go to a dozen different rivers to get a dozen pieces of information."
And once the information is obtained, then there is the possibility that what is pertinent to the Patuxent or Potomac might not be pertinent in the Choptank or Chester.
Spiers said the critical period of the yellow perch life cycle is when the fish is in the egg or young larval stage in February and March, before the aquatic plants begin to grow.
Once the water warms and submerged vegetation comes in, adult yellow perch will settle into the thick of things.
"The yellow perch is a creature of cover," Speirs said. "It likes grass beds, the areas where there are lots of tree branches down in the water and so on."
This year, DNR plans to study the yellow perch further, redefine the status of the species in various tributaries and simplify yellow perch fishing regulations.