Something in the water: N.S. man unsure what creature broke his arm in St. Margarets Bay

Glenn Singleton didn't see the creature that rammed into his arm while swimming in St. Margarets Bay, but he sure felt it.

Last Wednesday, Singleton and his wife arrived at their rented cottage on Boutiliers Point just outside Halifax for a few days of summer vacation, he recently told CBC's Mainstreet.

The Dartmouth man said he decided to go for a swim around 4 p.m. He entered the water cautiously since he was unfamiliar with the area, and noticed there was lots of seaweed.

He swam out a few lengths to get into clearer, chest-deep water where he rolled onto his back in a leisurely float.

"All of a sudden, there was a crack. It sounded like someone hit a home run. And the excruciating, instant pain was unbelievable," he said.

Singleton stood up and could see some kind of "white flash" as the water splashed around him, but couldn't see exactly what had hit him.

At the time, his focus through the shock and pain was grabbing onto his arm and "getting the hell out of the water," he said.

The arm was "kind of dangling" below the elbow, so Singleton said he lifted it and held it up as best he could while he got back to shore.

At first, Singleton said he thought he might have been stung by a jellyfish since the arm didn't swell right away. His wife dropped him off at the Dartmouth hospital to get checked out, and an X-ray was taken the next day.

The image showed a clean break in Singleton's left arm, and doctors told him that injury wouldn't have happened if he banged into a rock.

They said "whatever hit you had some significant propulsion and power happening," Singleton recalled.

There were also no bite marks or punctures through the skin. Singleton's original theory is that he might have been struck by a dogfish shark that followed smaller prey into shallow waters.

Boris Worm, a marine conservation biology professor at Dalhousie University, agrees that Singleton was likely hit by a fast-moving fish in pursuit of mackerel or other bait fish.

But, he said dogfish rarely come into the waters that shallow, so he has some other species in mind.

He knows tuna have been spotted in St. Margarets Bay in the past, and even though it's early in the year for them it's definitely a possibility. A young porbeagle shark might also be a possibility.

LISTEN | Glenn Singleton describes the violent encounter:

"They're both incredibly fast, so they could have quite an impact when they're really motoring," Worm said.

Another option might be a harbour porpoise, which Worm said looks like a small dolphin.

Whatever it was, Worm said it was likely so focused on chasing its food that it didn't recognize the figure floating on top of the water.

Attack in Maine

Singleton's encounter happened just days after a woman was killed in a rare shark attack off the coast of Maine.

Worm said experiences like these are reminders the ocean is a "wild place," and it's good to be aware there are so many other species living in it although such events "very, very rarely" result in injuries.

Singleton said he's been told his break should heal evenly without surgery.

Although he and his wife finished off their time at the cottage, he said, "I'm not going swimming for a while."