On August 13, at approximately 3:00 a.m., a land-based shark angler on the south side of Cape Cod hooked into a trophy-sized tarpon while using cut bluefish for bait. After an intense 25-minute battle, Hans Brings of Mashpee, Massachusetts beached the impressive silver king, took a few photos and videos for proof, and then returned it to the ocean. According a local fisheries biologist, Brings’ catch marks the first widely-reported instance of an angler catching a tarpon in Massachusetts waters in recent memory.

“I haven’t personally confirmed it yet, but I don’t have any reason to doubt it,” Massachusetts Division of Marine Fisheries biologist Ben Gahagan tells Field & Stream. “It’s been an odd summer up here. We’re getting a lot of strange tropical catches.”

Brings was fishing from the beach and had two lines out when the tarpon struck. “He went on a lot of long, powerful runs in the beginning, and I thought he might have been a larger brown shark at first,” the angler tells F&S. “Then, about halfway through, he started holding in a way that kind of mimicked what a rough-tail ray does. But later on in the fight he started doing a lot of head-shaking, and I knew it had to be something other than a ray or a shark.”

The tarpon went on a few more short runs in the wash before Brings finally managed to pull it into the surf. “At this point, I was very confused and a little tired because this thing had a lot of energy in it,” he recounts. “Eventually, I got it up to within five or ten feet of the beach and handed the rod to my buddy Mike. While I’m pulling it toward me, the head swings around, and I see the eyes, then the scales, and then the face. The face almost looks like a menhaden or a herring or something like that. I turned to Mike and said, ‘There is no way that just caught a tarpon.’”

Brings didn’t take any official measurements, but he estimated the tarpon’s length at approximately five to five-and-a-half feet. One video shared by a local news station shows Brings—who is 5 feet, 11 inches tall—lying next to the big tarpon for reference.

Gahagan says that a few days before Brings beached his tarpon, “a decently-sized barracuda was weighed in on Long Island Sound.” And he pointed to reports of local anglers catching such tropical species as sailfish, cubera snapper, and cobia in recent months and years. But in his 13-odd years working as a fisheries biologist in Massachusetts, he’d never heard of anyone taking a tarpon—until this year.

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“It’s totally crazy,” Gahagan says. “But I think when you step back and look at the patterns we’ve been seeing over the past five years, it’s not that surprising. With the warmer temperatures brought on by climate change, the whole northwest Atlantic is undergoing a lot of changes really quickly. We’re going to get these vagrants, these fish that stay with the bait in the warmer water, and they’re finding their way into places they just haven’t really been seen in the past .”