An ocean advocacy group is calling for unified action from Canadian and U.S. governments to protect the dwindling North Atlantic right whale population from extinction.

Oceana is launching its campaign in Toronto and Washington, D.C. on Thursday.

The group is asking both countries to expand existing protection measures for the marine mammals, with a particular focus on preventing ship strikes and fishing gear entanglement.

Twenty-eight right whales have died in North American waters since 2017, including eight in Canadian waters this summer, of a population numbering only about 400 animals.

Kim Elmslie, campaign director for Oceana Canada, said the bi-national campaign is asking officials for urgent, collaborative responses to the worsening crisis, as the world's oceans experience the effects of climate change.

"The species is still at risk of extinction, so we need to find solutions for this species across borders," Elmslie said in a phone interview from Ottawa on Wednesday.

Recommendations include reductions in vertical lines used in fixed-gear fisheries and fishery closures that would come into effect once right whales are detected in an area.

Oceana is also lobbying for stronger tracking of fishing vessels, limits on seismic blasting in right whale territory, an expanded task force of right whale experts and more long-term funding for research, including necropsies, which probe an animal's cause of death.

A supplementary report by Oceana Canada describes the history of the animal — named "right whales" because their slow swimming speeds and proximity to shore made them the "right" whales to hunt. After being hunted to near-extinction in the mid-1900s, the species made a slight rebound, but its status has taken a sharp decline in recent years.

Oceana Canada's report also details the agonizing deaths right whales suffer when entangled in fishing gear, taking six months on average to die, usually from drowning or starvation.

The campaign comes after a summer in which a spate of right whale deaths highlighted the cross-border policy considerations that complicate ocean conservation efforts.

Last week, Massachusetts' attorney general wrote to political leaders in eastern North America urging unity and action on right whale protections. In late August, the Maine Lobstermen's Association said it would pull out of an agreement that sought to reduce risk to right whales, arguing the rules were too restrictive and that Canadian fisheries and vessels posed the greatest risk.

Elmslie said complicated issues of intergovernmental collaboration are typical in marine conservation work, where large animals like right whales move through ocean regions governed by different laws.

Another challenge is the unpredictable impact of climate change in oceans, Elmslie said, making it difficult to draft effective policies as animals adjust their behaviour.

Right whales like to feed on small fish called copepods, and scientists believe the whales are following their prey into the Gulf of St. Lawrence in larger numbers, as temperatures rise in the more southern waters they used to frequent. This migration has put right whales at greater risk of ship strikes.

"They're encountering threats they've never encountered before, because their food is shifting, and we could continue to see further shifts in the years coming," Elmslie said. "That's what makes it challenging, is the unknown, and trying to be predictive in what you're doing."

Some of Oceana's recommendations aim to illuminate those unknowns, like funding more detailed necropsies on right whales killed in the Atlantic. Elmslie said this funding would fill in gaps about the greatest risks to the animals and would provide support for the scientists who carry out the physically and emotionally difficult work.

Canada strengthened its marine mammal protections last year, including vessel speed limits and minimum approach distances. Elmslie said Oceana's campaign is about expanding and improving existing protections.

She said she is optimistic that whoever forms government after October's federal election will remain committed to saving the species.

"There's no silver bullet to this," she said. "It is going to take multiple departments, multiple organizations, multiple scientists, multiple industry groups to continue to work on this and solve this."