Videos of the Wednesday morning incident near the Deauville Inn in Strathmere Bay were posted to social media.
The New Jersey State Police Marine Unite responded to the scene and initially thought the shark was sick, according to NJSP Sgt. Philip Curry.
After contacting the state's Division of Fish and Wildlife, authorities learned that sharks typically scope out areas of the bay with fewer predators to give birth, and may appear disoriented, according to Curry.
The shark was coming out of the water and swimming around aimlessly and, given the location and the shark's characteristics, there was a "good chance it was giving birth," the sergeant said.
Luc von Czoernig, of Sea Isle, was on a boat ride and had ended up at the Deauville Inn when he saw a fin. He went over to the area and began filming.
"The shark just seemed to be confused," he said. "Not aggressive, just checking out the docks and beach."
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