Alan Murray, Associated Press
Fly fishing teacher Chris Thomas, left, sorts through a screen for samples of insects used for bait in fly fishing near the Logan River in April.

LOGAN — The first time Chris Thomas made a successful cast and caught a fish, the creature jumped completely out of the water to take the fly. But it wasn't just the fish that got hooked. It was also the fisherman.

Thomas was taught to fly fish by his elderly, down-the-street neighbors who had decided he "played too much basketball."

"These two guys walked down the street one time and said, 'We're gonna do something to change your life,' and I didn't really believe that, but it has," Thomas said.

Nearly 40 years of tying flies and casting lines later, Thomas is teaching others the sport he loves through community continuing education classes as well as classes offered by RoundRocks Fly Fishing. With enrollment in one of his crash courses, he said, would-be fly fishers can get a head start of several years.

"If you start this out and you try to learn this without anybody showing you, it can take a long time," Thomas said.

That's because fly fishing is more than just the distinctive cast it's often associated with. Part physics, part entomology, part arts and crafts, the sport uses "flies" hooks decorated with ribbon and feathers to resemble actual bugs to tempt prey. And to know what to tempt them with is a big part of the battle.

Thomas helps his students with this in a hands-on lesson in creepy-crawlies, explaining where fish get their nourishment. Turns out the sport might be more aptly named if it were called nymph fishing, or larvae fishing, because "that's where the fish get the bulk of their protein."

To drive the point home, in a recent class Thomas and his friend Doug Wilkins trolled the Logan River with a large screen, pulling up an abundance of insects in their infancy to show the class what they look like and that they are there below the water. Thomas explains the creatures he captured in a Tupperware basin while calmly coaxing a leech off his forefinger. There's a salmonfly nymph, large, six-legged, two-tailed, delicious. There are a few tiny midges. There is even a sculpin, a small fish that makes a great snack for trout.

Once these below-surface foods are understood, Thomas said, it's easier to know what to fish with.

"It's very important to understand the life cycles," Thomas said.

After the explanation, Thomas sends the class around RoundRocks to find flies that resemble the creatures of the river. Size, shape and color are the most important factor, and the students return with a myriad of clever hooks that do indeed look like the bugs, a colorful, fuzzy assortment.

Bugs, according to Thomas, are the biggest factor in fly fishing. A fisherman must assess each time on the river what bugs are out, and therefore what insects the fish will be looking to eat. It's better to have a bad cast, he said, than bad flies.

"You have to be able to observe what's on the water and you have to be able to simulate, within reason, the insects that are out there," Thomas said. Casting comes into play, Thomas said, because it's important the fake fly move like real bugs would.

"The fish can get pretty particular," Thomas said.

Scott and Rhonda Ridge, students in the class, said they signed up to learn something they could do together in the great outdoors. But they didn't know how "involved" it actually would be.

"It's a lot more involved than I thought," Rhonda Ridge said. "I really didn't think there was any skill involved, and there's a lot of skill involved."

Bruce Smith, an 18-year fly fisherman, said he's taking the class with his wife, Shauna, so she can learn and go with him.

But he's doing a lot of learning himself.

"I'm learning a lot in the class, but I don't know how good a fisherman I am," he lamented. "(I'm learning) that I don't have a very pretty cast," Smith said. "And it's good to learn about all the different kinds of flies to use."

Wilkins said though he's been fishing for a few years, he comes to the class just to listen to Thomas. "I've learned something every time."

He takes his kids fishing, Wilkins said, and said the experience is at once challenging and meditative.

"I have an attention span of about a 2-year-old, I won't do it, I won't go up to Second Dam and hand a piece of hamburger and wait for a fish to bite," Wilkins said. "But with fly fishing, you can move up the river, it's always different, you always move. What's the fish doing? What's changing? Things are always changing."

"There's a lot of science involved in it, there's a lot of physics involved in it," Thomas said. "If you're observant, if you're visual, it can be great, for a visual person, there's so much. You can see the fly go down the river, you can see the fish, you can see the fish take the fly."

Wilkins agreed.

"When you see the fish come and take the fly off the top, it's just a great thing."