`Left-handed' fish is quite all right.

Byline: Mark Blazis

COLUMN: Outdoors

Lefties, flatties, doormats. You might think we're talking about different kinds of people, but from Cape Cod to Cape Hatteras, those are actually names for one of the most delicious and highly sought-after fish in the sea - fluke, also called summer flounder or plaice.

These flatfish are physically quite bizarre in the way their eyes have adapted to their pancake-like form. Both eyes migrate, as they grow, to the left side of their head. Consequently, fluke are referred to as "left-handed" even though they have no hands. Their belly is on their left edge (not underneath) as they lie flat on their pure white right side.

The fish camouflage themselves quite readily, changing color like chameleons to match the different bottoms they wiggle into and ambush from. From their hidden positions, fluke can lurch forward quickly, aggressively pursuing prey and sometimes even jumping out of the water in the chase. Their proportionately larger mouths are typical of a fish specializing in capturing moving prey. Fluke's active behavior differentiates them dramatically from other, much less athletic species of flounder.

It's easy to confuse fluke with other similar flatfish. It helps to know a little anatomy and taxonomy to key them out, recognizing a few distinctive features. Gray sole or witch flounder, for example, are "right-handed" and have an extraordinary number of fin rays - about 115 on the dorsal fin and about 100 on the anal fin. They have small mouths, indicating they hunt prey that is either sedentary or slow moving. Witches must be a minimum of 14 inches in length. They grow up to 20 inches, seldom exceeding 3 or 4 pounds. There is no possession limit or closed season on them.

Windowpane or sand flounder are "left-handed" and large-mouthed like fluke, but are shaped much rounder than other flounder species. Their front-most dorsal fin spines are separated uniquely and are distinctively fringed, too, rather than solidly connected like the other flounders. Minimum size is 12 inches. Big windowpanes could reach 18 inches and about 2 pounds. There is neither a possession limit nor closed season for them.

Yellow-tail flounder are "right-handed" and have a distinctive, arched lateral line. That's the line from the gill plate to the tail, serving to detect sensitively any vibrations in the water. They prefer sandy bottoms in depths from 100 to 200 feet. Seasonal changes in water temperatures don't seem to cause them to migrate toward, or away from, shore. They grow only to a couple of pounds. An 18-inch 2-pounder would be a good fish. There's no closed season and no possession limit, but fish must be at least 13 inches.

Winter flounder are small-mouthed, "right-handed" species, too, but their lateral line is straight. Their season runs from Sept. 26 to Oct. 25. There's a four-fish, 12-inch limit.

The only other relatively common flatfish in our waters is the "right-handed," much larger halibut. Only swordfish, tuna and sharks grow bigger here. Halibut have large, curved, sharp teeth, and their tail is concave, not rounded. Fish up to 400 pounds have been taken in our waters, and one eviscerated fish caught off Cape Ann weighed an improbable 615 pounds, so this Goliath's live weight would have been more than 700 pounds. Minimum size is 36 inches, with a daily limit of one.

Fluke season opens July 1 (which is Wednesday), and that means Christmas for a lot of fishermen. Fluke are coming into our shallow coastal waters now as temperatures rise. I know a lot of friends are getting their bucktail rigs, squid and sand lance ready to drift for them. You can take five of these delicacies a day, each a minimum of 18-1/2 inches.

In size, "flatties" are average fish, weighing a couple of pounds. "Doormats" are big fish of more than 8 pounds. Our state record is a 21-1/2-pound female. Females are much bigger than males. Females more than 15 years old can weigh around 20 pounds. Males don't live as long. A 7-year-old would be ancient, and would weigh about 5 pounds.

Smaller fish tend to be in shallower water. The big doormats stay mostly in depths greater than 50 feet. Fluke breed locally in the fall, more so between New York and New Jersey, moving out into much deeper water as temperatures drop, so the window of opportunity to catch them is short. Their season closes Aug. 13.

Whether you steam, poach, grill, bake or saute them, they're mild and delicious. It would be hard to find a sweeter fish to fill your freezer.

Mark Blazis can be contacted by e-mail at [e-mail].