Algae toxins spreading to top of food chain

A U.S. study suggests climate change is putting marine mammals in Haida Gwaii waters at greater risk from algae toxins.

A U.S. study suggests climate change is putting marine mammals in Haida Gwaii waters at greater risk from algae toxins.

Researchers in Alaska showed for the first time that two of the most common neurotoxins associated with harmful algal blooms — demoic acid and saxitoxin — are spreading to the top of the marine food chain.

Kathi Lefebre, a biologist with the U.S. National Oceanic and Atmospheric Administration who led the study, has said the same risk applies to marine mammals along the B.C. coast.

Lefebre and others found detectable levels of algae toxins in 13 species, including whales, walruses, sea lions, seals, porpoises and sea otters.

All the concentrations were well below food-safety guidelines for people who eat meat from the animals.

Demoic acid and saxitoxin are more common in temperate and tropical regions, where the algae that create them bloom more often and in greater numbers.

But parts of the Bering Sea have already warmed nearly 3 C in the last decade, and retreating sea ice has allowed for more ships that may be carrying algae toxins in their ballast.

Published in the journal Harmful Algae, the study looked at samples from 905 marine mammals that were hunted, stranded, or captured between 2004 to 2013.

About a third had detectable levels of one or both of the toxins.

Demoic acid was found in all 13 species, and in about two-thirds of the bowhead whales and harbour seals.

Saxitoxin was found in 10 species, with the highest prevalence in humpback whales — about half of the humpbacks in the sample had the toxin, which is known as the strongest of paralytic shellfish-poisoning toxins.

While the biologists could not measure any clinical signs of illness in the animals, they noted that the neurotoxins may have been a factor in the ship-strike death of a humpback whale.

In marine mammals, such intoxication is associated with a loss of ability to avoid ships and an increase in stranding.


Just Posted

Second dump site of Dungeness crab discovered

DFO confident new site related to April 2 dump of 250 more crab

Haida youth travels to New York for UN forum on Indigenous issues

Haana Edensaw presented her speech in Xaad Kil, Masset dialect of the Haida language

Nisga’a leader named UNBC chancellor

Dr. Joseph Arthur Gosnell is the first Indigenous leader to assume the role

On The Wing: Hazy seas and dead Krill

Large die-off of krill in Delkatla Bay

QC food bank needs cash

Feed the People program shuts down for month of May

VIDEO: Killer whales hunt for seals in Vancouver harbour

Bigg’s killer whales feed on marine mammals like seals, sea lions, dolphins and even other whales

VIDEO: B.C.’s waving granny gets incredible send-off from school kids

Tinney Davidson has been waving at students on their way to school for over 11 years, but is moving in a month

Struggling B.C. adoption agency elects new board that intends to keep it open

The previous board announced that Choices would close May 31

Vancouver man, 19, charged in human trafficking case involving teen girl

The 16-year-old girl was reported missing and later discovered in Vancouver

Blaine, Wash. inn owner, charged with smuggling people into B.C., granted bail

Robert Joseph Boule ordered to turn away anyone indicating a plan to enter Canada illegally

RCMP arrest B.C. man following threatening Vaisakhi Facebook post

Post made reference to pressure cooker bomb at massive Surrey parade

Northern B.C. high school student reaches 100,000 followers on YouTube

Voice actor, animator, Jericho Fortune has more than 30-million views on his channel GTAGAMER222

University mourns student who died in B.C. canoeing accident

Andrew Milner, 19, was in his second year with the University of Calgary’s basketball program

Most Read