When about 10,000 anglers trudge onto Gull Lake next Saturday near Brainerd for the world’s largest ice-fishing contest and a chance to win more than $150,000 in prizes, they’ll immediately face a key decision:

Fish shallow or fish deep?

“If you want to catch a big fish and win the tournament, your odds are better in deeper water — the history of our catches have proved that,’’ said Bob Slaybaugh, 47, who has been a volunteer with the Brainerd Jaycees $150,000 Ice Fishing Extravaganza for its entire 24-year history.

“But if you just want to catch a fish, Gull is loaded with small walleyes 13-14 inches, and those will win a contest prize,’’ he said. “They are typically hanging out in the weed edge or inside the weeds from 18 to 22 feet deep.’’

Two years ago, Luke Botzek, 30, of Foley, Minn., chose to fish deep.

It was a smart move.

He landed a 6.4-pound walleye, a beauty that won him the top prize — a new four-wheel drive pickup. It was his first time fishing the event, and he caught the monster in 60 feet of water using a minnow.

“A lot of it, honestly, was perseverance and luck,’’ Botzek said last week. He used a borrowed fishing rod and had no electronic fish-finding equipment.

“My buddies marked fish about eight feet off the bottom with their Vexilar, so I reeled up about that far,’’ Botzek said.

“I felt a tug and set the hook hard. I thought I had a tullibee.’’

Instead he had a lunker — and a new truck.

“It was an awesome experience,’’ he said.

If you’ve got your eye on that new pickup, know that it generally will take a fish as big as Botzek’s to win top prize.

“On a good year, with consistent weather, it’s typically going to be a six- to eight-pound walleye that will win it,’’ Slaybaugh said. “Hole in the Day Bay [where the contest is held] has good structure and is real conducive to big walleyes. Typically, the largest ones come from 40 to 55 feet.’’

Whatever bites

Of the 23 contests held since 1991, walleyes have won 12 times, northerns and burbot, also called eelpout, have each won five times and a 2.2-pound tullibee won in 2006.

Last year, Bror Linnerooth, 23, of Brainerd, won the contest with a 4.4-pound northern he caught in 35 feet of water with a fathead minnow impaled on a red hook.

“I was fishing for whatever would bite,’’ said Linnerooth. “I had six-pound test line with no leader, so I was lucky he didn’t break my line.’’

When he finally landed the fish, he figured he’d win something, but didn’t expect the top prize.

“Every year it’s a six- or seven-pound walleye that wins it,’’ said Linnerooth, who has fished the contest since he was a kid.

A look at the winning fish over the years shows some other changes: 9-pound walleyes won the contest three consecutive years from 1997 to 1999 — but none that big have been caught since. And eelpout, ranging from 4.3 to 8.7 pounds, won five consecutive years from 1992 to 1996 — but the species hasn’t won since.

“The first few years of the contest, eelpout were plentiful,’’ said Slaybaugh. “There used to always be some in the top 10. But over about the past seven years, we’ve weighed in fewer and fewer. In some years, we haven’t even had one.’’

More burbot showed up in the Department of Natural Resources gill net survey last summer, so more could show up in the registration tent on Saturday. Only one was registered last year.

A few tips

Slaybaugh lives on the Gull Lake Chain and is director of Confidence Learning Center near Brainerd, the main beneficiary of money raised by the contest. Proceeds also go to other charities. Slaybaugh offered these observations of some previous winners’ fishing techniques:

“They seem to be guys who move a lot. They look for fish that are active instead of sitting on a fish that’s inactive. They might move every 10 or 15 minutes.’’

And be prepared.

“If you’re fishing in 40 or 50 feet of water, a school of tullibees can come in 10 feet under the ice,” Slaybaugh said. “They won’t hit that walleye jig, so you need a second rod with lighter tackle and a wax worm ready.’’

And perch has been very active recently, he said. He recommends a small teardrop jig and wax worm or a Buck-Shot rattle spoon tipped with a minnow head.

Come to have fun, but don’t bring high expectations, both Linnerooth and Botzek say. While 1-in-10,000 odds are way better than the odds of winning the lottery, winning is still a long shot.

Botzek returned to fish the contest last year.

“I didn’t catch anything,’’ he said.

He’ll be back this year, as will Linnerooth

“I just go for the fun it,’’ Botzek said. “That’s what fishing is supposed to be — fun.’’

Said Linnerooth: “It’s a blast just being out there with everyone.’’