Groups of 30 to 1,400 basking sharks have been seen in waters from Nova Scotia to Long Island. Photo by Chris Gotschalk/Creative Commons.

A species of large (harmless!) shark has been gathering in large groups off of the northeastern United States and Canada, including off the shores of Long Island.

The National Oceanic and Atmospheric Administration says groups of 30 to 1,400 basking sharks have been seen in waters from Nova Scotia to Long Island, New York.Sightings of basking sharks are common, but seeing them in such large groups is not.

The reason why the animals congregate has not been clearly determined, although it is thought to be related to feeding, socializing, and/or courtship given behaviors in other shark species.

Read more at ScienceDaily.