People reported seeing the shark in the area of the river near Navesink Avenue, Rumson police said Thursday.
The New Jersey Division of Fish and Wildlife advised that no sightings have been confirmed but "there is a possibility that sharks could be in our local waterways," police said.
There have been sightings of sharks in the Navesink River and elsewhere along the Jersey Shore in past years.
Area resident Paul Cameron posted a photo of a pair of Bimini Bahamas sharks resembling those spotted near Navesink River docks. Cameron said that the ones he has seen in local rivers measure at least six- to seven-feet-long.
Bull sharks can grow up to 12 feet long and are among the three most likely species of shark to attack humans, though attacks are very rare, according to marine experts.
NJ.com reported that in 1916, deadly shark attacks terrorized Monmouth and Ocean counties, killing four swimmers.
Those fatal attacks were in Spring Lake and Matawan Creek -- about 10 miles from the sea, according to the Global Shark Attack file. That summer, there also were non-fatal shark attacks on young swimmers in Atlantic City and Cliffwood Beach (Monmouth County). The surge in fatal shark attacks partly inspired the book and movie “Jaws.”
The last recorded fatal Jersey Shore shark attack came in August 1926 when an 18-year-old swimmer was killed in Seaside (Ocean County), according to The Washington Post.
The last shark attacks in New Jersey were non-fatal incidents. In July 2011, a fisherman wading in Egg Harbor (Atlantic County) was bitten in the boot. And in November 2013, a 16-year-old reported his bodyboard was bitten by a shark in Bay Head, also according to the Global Shark Attack File.
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