Experts say humans are likely to blame in the deaths of three of the six North Atlantic right whales recently found floating lifeless in the Gulf of St. Lawrence. But they remain hopeful the attention drawn by the grisly discoveries, and an uptick in marine research, will help conservationists safeguard this dwindling population before it's too late.

Tonya Wimmer of the Marine Animal Response Society said the team of federal fisheries officials, veterinarians and other marine experts who were part of the trio of necropsies in P.E.I. cannot definitively say what caused the deaths until laboratory tests are complete.

However, preliminary findings suggest two of the massive male mammals suffered blunt trauma, most likely from a vessel. Another female was found snarled in fishing ropes.

“They were hit by something big. Something big enough or going fast enough that it would cause the bruising and internal injuries we saw,” she told CTV Atlantic on Tuesday.

Wimmer said it is not clear how long the female was stuck in the fishing gear, but she estimates it could have been entangled for a few weeks. The other three dead whales have not been examined.

Dozens participated in the massive job of hauling the three animals between 60 and 70 nautical miles to shore, dragging them onto land with excavation equipment, completing the post-mortem examination, and collecting samples for researchers to analyze in laboratories.

Finding six North Atlantic right whales decomposing off the coast of P.E.I in one season was more than enough to raise alarm bells for researchers. They are said to be among the most endangered large mammals on Earth. Wimmer estimates there are only about 525 left.

“(It’s) very unusual,” she said. “In the course of a year, you might only have one or two (dead).”

Kim Davies, a post-doctoral fellow at Dalhousie University’s Department of Oceanography, studies the species’ habitat and migration patterns. She said the loss of six right whales is particularly devastating because birth figures are on the decline.

“There were only five calves born this year,” she said. “Five is a very low number.”

Right whales are a migratory species that spend the spring, summer, and fall along Canada’s east coast. In the winter, they head for warmer waters near Florida and Georgia. However, their exact whereabouts throughout the year is largely unknown.

Davies said research into the distribution of right whales started in 2010, but migration patterns in Canadian waters have changed since then. Efforts to track their movements in the Gulf of St. Lawrence only started as recently as 2015, she said.

“There is still a lot to be learned about where these animals are, when they are there, where their aggregations are, and how they get in and out of these areas,” Davies said.

Her hunch is that the recent spate of deaths is the result of the whales entering the shipping lanes that criss-cross the Cabot Straight, a 110 kilometre-wide outlet flanked by Newfoundland to the north and Cape Breton, N.S., to the south.

“We don’t know where the crossing points are at this point,” she said. “Really all we know is that they are present there. This summer is our first large scale collaborative effort to find out why they are there, and if there are some high-use areas they will return to year after year.”

While the sight of multiple whale carcases on shore is a disturbing sight for any researcher, Davies is hopeful the brisker pace of research will mean speedier conservation measures to protect the pods that traverse the Gulf of St. Lawrence.

“There are conservation measures to protect right whales in the Bay of Fundy and southwest Nova Scotia. Those protection measures took decades of research to establish. Now I feel like we are ahead of the game a little bit,” she said. “If there is a bright side, that’s what it is.”

With a report from CTV Atlantic’s Kelland Sundahl