When you're dragging plugs in certain lakes and rivers, be careful what fish you call a muskellunge.

Should you try to impress some St. Lawrence River fishing guide by whipping out a photo of the nice muskie you caught the previous summer in Conesus Lake, you can expect a polite but firm correction.

"That's a heck of a fish," your captain will declare. "But it's a norlunge, not a muskie."

Well, to the average angler, a big fish is a big fish. I doubt that anyone who's caught a whopper tiger muskie in New York since the Department of Environmental Conservation started rearing them in 1968 bothered to add an asterisk when they logged the trophy in their fishing diaries.

MUSKIE OR TIGER, WHAT'S THE DIFFERENCE?
It may look like a muskie, feel and even smell like a muskie. But it's really not Esox masquinongy at all.

Rather, it's a hybrid -- part female muskellunge and part male northern pike. It's a tiger muskie, also known as a norlunge.

Norlunge -- sterile and unable to reproduce -- generally don't live as long or grow as big as purebred muskies. Even so, tiger muskies have a few things going for them.

For starters, norlunge are really somewhat easier to catch than true muskies. State biologists also appreciate the hybrids' voracious appetite for alewives and other forage fish that tend to take over a small lake in the absence of large predators.

The tigers' infertility is another plus, for if the toothy predators turn out to be a poor fit in any given lake, the problem can be solved by simply canceling any further stockings.

When you add dozens of norlunge-stocked lakes and rivers to the smaller number of Empire State fishing holes that have historically held purebred muskellunge, New York sportsmen planning their lunker quests now have more than 100 muskie waters to choose from.

The following lakes and rivers are the cream of that crop:

CHAUTAUQUA LAKE
The state's only purebred muskie hatchery is on Chautauqua Lake's west shore at Prendergast Point. Fisheries biologists net muskies in spring, summer and fall to make sure all is right with the natives.

The 2007 spring netting, conducted to gather eggs needed for stocking programs at several other western New York lakes and rivers and to supplement Chautauqua, yielded 188 mature muskies measuring between 30 and 47 inches long.

"Our goal last spring was to catch 28 muskies per net, and we averaged a little better than 30," said Mike Clancy, a DEC Region 9 biologist, whose office number is (716) 372-0645. "So based on that alone, I'd say the fishery is quite healthy at the moment."

On Chautauqua Lake, the minimum creel length for muskies is 40 inches, and a four-footer would be considered a large one.

"I had an unconfirmed report of a 57-incher last year," said Clancy, "but it's known for numbers of muskies, rather than really big ones."

Chautauqua Lake lies in the southwest corner of the state at Jamestown. It spans 13,100 surface acres with two distinct basins, north and south of the Interstate Route 86 bridge at Bemus Point. The supports of the federal highway bridge shelter many muskies, but the speed-trolling techniques favored by local guides also work well in many other spots.

A free fishing map, available from the Chautauqua County Visitors Bureau at (716) 753-4304, will help visiting anglers find the strike zone.