A clam rests on rocks after being dug up by Shelly Carlson of Manchester, Connecticut on Sears Island in Maine in July of 2014. Credit: Brian Feulner / BDN

The heat wave that struck the west coast at the beginning of July could have killed more than a billion shoreline animals, the Canadian Broadcasting Corporation reported this week.

Inland temperatures in British Columbia reached more than 100 degrees Fahrenheit over the Fourth of July weekend, and the Salish Sea shoreline reached around 122 degrees, according to researchers at the University of British Columbia.

The high temperatures caused the mass death of mussels, clams, barnacles and sea stars on the shoreline. Marine biologist Chris Harley, who works at UBC, told the Canadian broadcasting service that most intertidal animals, including various shellfish, can typically survive shoreline temperatures around 86 degrees for short periods of time. However, when temperatures rise or remain high for an extended period, shellfish and intertidal animals are less likely to survive.

Harley and a team of marine biologists recorded that areas of the British Columbian coastline reached more than 120 degrees, and maintained that temperature for about six hours. Low tides in the afternoons left many sea creatures stranded and exposed to unsustainable temperatures, causing many to cook in their shells.

Harley said that the amount of shellfish and other intertidal animals that were killed due to the heat wave will have a ripple effect on the water quality in the Salish Sea. He told the CBC that mussels and clams help to filter sea water, and the loss of so many organisms will have direct environmental impacts.

It could take up to two years for the intertidal population to recover from the number of deaths caused by the heat wave, according to Harley. Along with the warming of the intertidal zone, coastal temperatures could rise by around 5.4 degrees in the next couple of years, impacting temperature-sensitive flora and fauna, Chris Neufeld of the Bamfield Marine Sciences Centre on Vancouver Island told the CBC.

Leela Stockley

Leela Stockley is an alumna of the University of Maine. She was raised in northern Maine, and loves her cat Wesley and staying active in the Maine outdoors.