It’s a good thing Yellowstone Lake fishing guide Nicolas “Nicky” Trevino cut his teeth in the Pacific Ocean’s rough seas.

The lake — the largest high-elevation lake in North America — can go from glassy to ghastly in short order. Even in the sturdy Grady-White cuddy cabin fishing vessels used by the guides at Yellowstone National Park can face danger in the swells and whitecaps churned up by mountain gales sweeping across the 136-square-mile famous lake. But what’s an adventure without at least a little fear?

Trevino’s boating experience started early at the age of 8 or 9, he said. He remembers wanting a tri-hull 60 years ago — the first time he fell in love with a boat. Now he runs a guide service in Idaho targeting smallmouth bass in the Snake River reservoirs — that is, when he’s not on Yellowstone Lake.

Trevino is living out his dream after retiring from his decades-long career as an accountant.

“I love being on the water,” he said while piloting the vessel across choppy water to the Cub Creek area. “How can you explain when you’re in your happy place? I just love it.”

Interestingly, the 69-year-old adventurer doesn’t really like to eat fish. There are a couple species, like halibut, that he enjoys on rare occasions, but he’d just as soon have a steak.

Sitting in an office typing numbers on keypads made his escape-theory dreams of a life at sea seem more important. But on this day there was no time for dreaming. The lake was chopping on the way out and, within an hour, there were 3- to 4-foot swells and occasional white caps tossed the boat while lines were out.

Typically Trevino’s anglers toss crank baits and spinners from some nice rod and reel combos. They are aided by full graphics on each boat. But when the wind is up — he faced 30-plus mph gusts that day — you have no choice but to use the down riggers.

Xanterra employed guides provide all the tackle needed for the trip. That said, if you hook into a lunker and end up losing or breaking the pole in the fight, guests are responsible for the loss. The setups are strong and the reels are smooth, but if you have a combo you would prefer to use, it’s fine to bring your own.

It’s hard to believe one person can set-up the fishing gear for multiple people, keep the guests happy and safe and find fish quickly in turbulent water. Yet, Trevino made it look easy despite the extremely challenging conditions. All the while, he naturally cares for clients and wants to make them as comfortable as possible.

“The clients choose how they want their trip [to unfold],” he said.

He has a lot of foreign visitors wanting his services; spending the day on the lake is one of the most intimate encounters you can have in the ecosystem. Some folks don’t even care about fishing. They can bring adult beverages, wear swimwear and watch the shoreline for wildlife if they would rather.

The lake is popular with anglers seeking to hook a giant lake trout or a native Yellowstone cutthroat. Regulations require using lures, but not all types are welcome at the lake where conservation comes first. You can’t use rubber lures or lead, and you have to use barbless hooks. No live bait or attractants are allowed.

Fishing in Yellowstone

Charter guide boats are available throughout the day, with a minimum of a two-hour trip required. Advance reservations are recommended. Short notice reservations can be made at a Xanterra activity desk, but are subject to availability. Anyone 16 years or older who intends to fish must purchase a Yellowstone National Park fishing permit, even if you already have a Wyoming fishing license. A three-day license is $40. Or, you could buy a license for the entire season for $75.

Despite the bait regulations and added expense for licensing, there are opportunities at the deep lake to catch a bucket-list fish and folks will stand in line for a chance to reel one in. This past July a 35-pound lake trout was caught in the Hickey Brothers’ gill nets. The company subcontracts with the National Park Service for the constant efforts to save the native fish population of Yellowstone cutthroat trout. The conservation plan began in 2008 and they have already removed over 165,000 lakers in 2025.

Lake trout feed on cutthroats and threaten the native fish’s existence in the ancient waterway.

Trevino’s daily experiences at Yellowstone have already made him an expert in finding and catching fish. But, if you want to have the most fun, he advises people make reservations from opening day of the guide service to the end of June for the best fishing.

“The guide was very knowledgeable and engaging and made sure we caught fish,” said Norma White, who booked a trip and loved that the guide was willing to clean the fish they caught. “I highly recommend the guided trip.”

The Xanterra Travel Collection also offers boat rentals for those who want to self-guide their adventure. The office is at the Bridge Bay marina.

If you smell burgers on the grill while at the marina, it’s more than likely guide service employees grilling out. The employees are very close, Trevino said. There are four new guides this year, which is unusual.

“The positions don’t turn over very often. It’s a nice little gig,” he said. “We’re like a family.”

Trevino plans to be back again next year. He loves living in the park — he has a camper — and says he loves staying in the geothermal landscape with all its fascinating wildlife.

“I like the expanse of this park. You can drive for hours, you know, and hours and not get to either end. And [I like] the remoteness of it — I mean, to get in parts of the backcountry, the only way back there is by boat,” he said.

Guides work from about the second week in May through Sept. 10 and tours start at $270 for up to five people per boat.

Guided fishing/sightseeing charter boats are not bookable online. Contact Central Reservations at 307-344-7311 between the hours of 7 a.m. and 7 p.m., seven days a week, to book a reservation. For Trevino’s Idaho guide service: trevinoguideservice.com/.