It is a popular hobby in Europe and is starting to pick up here in the United States.
The mystery. The muscle. The meaning.
"So this is a good example of things we want to get out: anything sharp that kids could step on at the beach," Trisha Timm of YouTube Channel CatchYaLaterCrew told TODAY'S TMJ4's Jesse Ritka.
Timm pulled a sharp metal object out of the Kinnickinnic River using a high-power Neodymium magnet.
"That's 1,200 pounds by Brute Magnetics; we like them a lot. It lifts that much up in the correct conditions, so as long as it clinks flat, is solid metal, maybe pretty darn thick, it'll stick."
The CatchYaLaterCrew has their own YouTube channel and have been magnet fishing since November, but the hobby has been going on in Europe for much longer.
"The UK has a huge boom in it because they have the war and they pull up all sorts of things. Out here, we just get random cool stuff, sometimes things that aren't worth much," Timm said.
They have pulled up everything from nails to knives, enjoying every moment.
"It's fun because you never know what you're going to get," Timm said.
It doesn't take much to be a modern-day treasure hunter: gloves, rope, a very powerful magnet, plus a lot of patience. Sometimes, they pull up treasures; other times, it is just a tree. But, occasionally, the magnets attract more dangerous metals as Ritka found as she tried out the magnet. "That's definitely a piece, oh, that's a razor!"
Timm said this is part of the reason they are out on bridges and along the riverways. "There shouldn't be these things in the water in the first place!"
So the CatchYaLaterCrew will continue to clean the waterways while spreading the word about their unique hobby.
Latina Cantrell was walking to work when she noticed the crew. "It's something I've never seen before, so it's totally cool. It's something I would love to try, so if I get my hands on some stuff like this, I'm trying it out."
Timm and the crew would love more people to try it out because that would mean more manpower to help clean up what others have left behind,
"The biggest thing is we're getting everything out of the water so as long as we get things that shouldn't be there." All while enjoying the weather and having a few laughs. Combining the thrill of the hunt with a love for the environment.