It was, according to reports, just the fish. It was aggressive, grew quickly, had a taste for non-game fish, adapted to high lakes and was a worthy addition to any menu.

So, five years ago, the Utah Division of Wildlife Resources planted "splake" in Fish Lake, and has been doing so every year since.What is a splake? A cross between a male brook trout, sometimes called the speckled trout, and a female Mackinaw, or lake trout. The reverse union, female brook and male lake trout, called "brookinaw," has not produced offspring that is as desirable.

The fish were put in Fish Lake for two main reasons: 1. to put some feeding pressure on the growing number of undesirables in the lake - the chubs, suckers and perch; and 2. to provide a game fish that would take pressure off the lake trout.

Reports said the splake would do both well. They also said the fish would grow large, up to 10 pounds, and that it would be easier to catch than the more finicky lake trout.

It has only missed on one point. They are not, said DWR biologist Dale Hepworth, "growing as large as we'd expected."

This has also meant that the fish have not yet reached a size where they can begin to help control the growing number of non-game fish in the lake.

Splakes have, however, balanced the scales in another area. They are, said Hepworth, "a much better winter fish than we expected."

That is, fishermen have been and will, as long as ice covers Fish Lake, catch splake - eight times as many splake as they will rainbow. This in spite of the fact that the DWR plants about 200,000 rainbow in Fish Lake each year compared to only about 50,000 splake. And splake cannot reproduce in the wild, while the rainbow can.

Which means fishermen have had, and will continue to have, a good opportunity to catch and keep a limit of splake, and hopefully return the lake trout they might catch to help preserve the resource.

Splake are not, in Fish Lake, anyway, getting as large as biologists would like. Estimates indicated they should reach 10-plus pounds in the wild. Those kept in Utah hatcheries have, but those in Fish Lake haven't. The average catch at the lake is around one and a half pounds. The state record of three pounds, one ounce, set this winter, came from Fish Lake.

Hepworth isn't sure why splake in Fish Lake aren't showing more growth. The fish, he said, need to be in high lakes that are deep and in water that is cold and clear - like Fish Lake. He feels competition with other species might be part of it.

Biologists will be watching other Utah lakes - Blind Lake, Joe's Valley, Porcupine and one of the Uinta lakes - to see how planted splake there grow.

Still, even though smaller than they should be, splake have been a real draw to Fish Lake this winter. According to Gary Moulton, manager of Lakeside and Fish Lake lodges, pressure has been steady and, at times, heavy.

"On weekends," he said, "we're getting 50, 60 cars . . . and everyone seems to be doing well. The rainbows are 12 to 16 inches, and the splake 14 to 20 inches, or about two pounds. The biggest lake trout has been 22 pounds, but most are the 12- to 18-pound range."

Out on the ice this past weekend, Kevin Skenandore and Russ Peterson of Richfield, did, in fact, do well. They limited out on splake (four each), returned at least that many more along with all rainbow and lake trout, and hooked a couple of nice perch, one near the two-pound mark.

Both said they were there for splake, both said they'd come often to Fish Lake, and both put the splake at the top of their dining list.

There is, too, a side to fishing at Fish Lake not often available. Because of the clearness of the water, and the illumination of the ice, fishermen peering down close through a hole in the ice have a clear view of the bottom in many places, and of the fish, and the hits and the misses.

It was, said angler DeEtte Gunderson, "fun to watch the fish come up and take the bait. You expect them to come up every time and take it, because you know they are hungry, and yet they don't. It was fun just to watch."

The secret to Fish Lake fishing is, as it is anywhere, first finding where the fish are hanging out. Last week, said Skenandore, the fish were out in 30 feet of water. "This week they're shallow, in about 17 feet of water."

One of the favorite lures is a three-inch white plastic grub tipped with carp meat.

There is, on the bottom of Fish Lake, a covering of moss in water up to 75 feet. In the summer it's an annoying problem. In the winter the moss retreats and fishermen are able to hang the lure just over the moss.

According to Hepworth, splake fishing, weather cooperating, should stay good as long as there is ice on the lake, or until sometime in April. After that, he said, the rainbow should start showing up in more creels.