As another beach season draws to a close on Cape Cod, researchers are trying to figure out what's driving the increase in shark sightings and encounters.
One prominent researcher suggests the presence of younger and smaller great white sharks this summer could be playing a role.
Greg Skomal, a state marine biologist leading a five-year study wrapping up this year, says his team spotted 149 great whites off Cape Cod in July, more than double the 74 observed last July and the 120 in 2016.
Just last month, Massachusetts experienced its first shark attack on a human since 2012.
An increase of great white shark sightings and encounters have occurred off the coast of Cape Cod this summer. Pictured: Sharks swim close to shore off Monomoy National Wildlife Refuge in Chatham, Massachusetts, date unknown
Researchers say the presence of younger and smaller great white sharks could be playing a role. Pictured: A dead great white shark lies on the shoreline in Truro, Massachusetts, August 23
He said somewhat smaller great whites - measuring about eight to 10 feet - appeared to make up a greater number of the sharks observed than in year's past, though he said his team is still analyzing the data.
Skomal suggested more younger sharks could be contributing to the encounters that are increasingly being captured in viral photos and videos, particularly those of sharks snatching fish off anglers' hooks.
Smaller sharks, he said, tend to prefer large fish like striped bass prized by recreational fishermen, while larger adult sharks measuring up to 15 feet typically hunt seals.
'Cape Cod may represent a productive feeding ground not just for mature white sharks, but also for juveniles,' Skomal said. 'It's something we'll certainly be watching out for.'
The presence of younger white sharks in Massachusetts waters isn't totally unheard of.
The waters between Cape Cod and New Jersey have been long been considered a regional white shark 'nursery' where great whites spend the first years of their life before gradually expanding their territorial reach.
But more frequent spottings of juvenile sharks could suggest a broader recovery for Atlantic white shark populations, a phenomenon that's already been documented on the US west coast, said George Burgess, director emeritus of the International Shark Attack File, a database maintained at the Florida Museum of Natural History in Gainesville.
'If anything, it's indicative of a healthy population,' Skomal said. 'As the white shark rebounds across the East Coast, we should be seeing a broader range of sizes.'
In August, William Lytton, 61, of New York, escaped a shark attack off Truro, Massachusetts, with severe injuries to his leg and arm. Pictured: Lytton 28 has his vital signs checked at Boston's Spaulding Rehabilitation Hospital on August 28
RLytton said, in hindsight, he took an