Warm oceans spelling trouble for Cape Breton ecosystems, threatening natural disasters

SYDNEY, N.S. — Bodies of water too hot to support species. More intense natural disasters. Erosion and harmful bacteria.

These are a few of the consequences Cape Breton could experience following the ongoing North Atlantic Ocean heatwave. The region has already experienced some of these effects, according to Atlantic Coastal Action Program (ACAP) Cape Breton executive director and local ecosystems expert Kathleen Aikens.

“The unprecedented temperatures in the oceans at this time of year are pretty scary,” she said. “It’s particularly concerning because it takes a lot of energy to heat our oceans. It’s a good thermometer of just how hot it is.”

Several parts of the Atlantic Ocean were first hit with higher-than-normal temperatures as early as April. In July, several reports said temperatures measured in the ocean were the warmest since tracking began in the 19th century. Near the British Isles, some temperatures have been up to 5 C warmer than historical averages.

Atlantic Canada isn’t exempt from extraordinarily warm ocean conditions. Virtually all of the water off of Cape Breton’s coast is being measured at an “above normal” temperature, according to SaltWire weather specialist Allister Aalders.

Much of ACAP Cape Breton’s work is in ecosystems such as streams or rivers flowing into oceans. Aikens said there is a connection between water conditions in the ocean and freshwater bodies inland — meaning warm ocean water leads to even warmer inland freshwater.

“Species like salmon and eels who migrate between the two habitats face stresses in both environments, which is concerning,” she said.

“The freshwater environments are at a higher level of concern than ocean environments for many of those fish species because it’s harder for them to find escape in rivers and streams, which heat up more rapidly.”

These threats in river environments have led the Department of Fisheries and Oceans to take action to protect some fish. The department closed much of the Margaree River to recreational fishing in July because it was too warm.

Between the inland and ocean environments — at the shoreline — some of the harshest impacts of heat waves take place. Mussels and snails are among the species living in these areas.

“We actually expect, based on the temperatures we’ve been seeing, that there’s been some significant mortality this year.”

‘Human Impacts are scary’

As the ocean heatwave carries on, it steepens the potential impacts of adverse weather events — including natural disasters. Aikens pointed out hurricane season is just around the corner.

It’s a sobering thought as it’s been almost a year since Hurricane Fiona devastated Cape Breton. Warm oceans are the fuel that makes hurricanes strong and, sometimes, catastrophic.

“The human impacts of hurricane seasons are scary,” Aikens said. “We lived through Hurricane Fiona here and no one wants to see a repeat of a storm of that intensity.”

Aside from the immediate dangers of a major hurricane, those storms such as Fiona have left some longer-lasting effects. Fallen debris can block escapes for animals. Certain debris such as trees can dry out enough to become wildfire fuel.

Warmer water can contribute to erosion and other hazards close to shore. In the Bras d’Or Lake, less freezing in colder months is expected. That can lead to more erosion when powerful winter storms come through. Long periods of hot, dry weather can contribute to blooms of blue-green algae.

Many of these factors together pose economic threats, such as through tourism, or health risks.

“Fundamentally, we all rely on having access to clean water and having access to healthy environments.”

‘It’s like bathwater’

On a hot day, like on Monday at Dominion Beach Provincial Park, the water’s exact temperature is the last thing most swimmers think about while cooling off on a hot day.

“It’s the same as last year,” said one beachgoer.

Others are paying attention a bit more carefully.

A lifeguard who has worked at the beach right on the Atlantic Ocean the past six years described conditions as ‘like bathwater’ and the ‘warmest we’ve ever had here.’

He wasn’t surprised to hear about records being broken across the ocean this summer.

In Cape Breton, those uneasy feelings of adverse climate effects are fresh after last year’s hurricane. Aikens said people can expect to see effects on a more individual level, such as when people lost homes to the storm last year.

The unpredictability of the changes in climate can leave locals stressed about what’s to come — especially those already hit by a severe event.

“As we go forward into the next hurricane season, (we) should be mindful of our own mental health around this,” she said. “It’s normal to have pretty significant anxiety after experiencing that. It’s thinking about preparing your own home, but also your own emotional health.”