Quantcast
Climate

Loss of Arctic Sea Ice Eliminates Major Barrier for Parasites in Marine Mammals

By Tim Radford

The great Arctic thaw—up to 50 percent of sea ice by area and 75 percent by volume in the summer season—could be offering new opportunities for one of the planet’s most successful parasites. Toxoplasma gondii, an infection spread by almost all cat species, has been identified for the first time in the western Arctic Beluga whale.

Uw

The parasite—Toxoplasma gondii—commonly spread through most species of cats has recently been identified in the Arctic Beluga whale. Photo credit: Wikimedia commons

Toxoplasma is found almost everywhere that cats settle: domestic pets, ocelots, cougar, wild cats all carry and spread oocysts of the parasite (structures it uses to transfer to new hosts) in their feces, to be spread further with discarded cat litter.

The parasite is notoriously hard to kill. Scientists store their samples in sulphuric acid, and the creature can survive unharmed in bleach. It is, however, routinely killed by freezing conditions, or boiling water.

The suspicion is that with the steady, sustained warming of the Arctic over the past 30 years, chiefly because of a buildup of carbon dioxide in the atmosphere, the retreat of the ice has begun to allow new traffic in parasite infections.

Another parasitic killer, a new strain called Sarcocystis pinnipedi, normally found only in the highest, iciest latitudes, has been linked with mass deaths too—406 grey seals died in 2012 in the north Atlantic. It has also been observed to kill Steller’s sea lions, Hawaiian monk seals, walruses, grizzly bears and polar bears as far south as British Columbia.

In the case of Toxoplasma, warming polar summers could have created conditions in which the parasite could find new warm-blooded hosts further north. In the case of the second parasite, the loss of ice has meant a greater mixing of species, and allowed Sarcocystis to find new hosts in warmer waters.

“Ice is a major barrier for pathogens,” Michael Grigg, of the U.S. National Institutes of Health told the American Association for the Advancement of Science annual meeting here. “What we are seeing with the big thaw is the liberation of pathogens gaining access to vulnerable new hosts and wreaking havoc.”

Toxoplasma can also infect people: it is the leading cause of infectious blindness in humans, and can be dangerous to unborn children and to people with compromised immunity.

It has been found in human communities in northern Quebec, perhaps spread by the consumption of dried seal meat. The discovery of Toxoplasma in Beluga whales has begun to worry health officials. Belugas are part of the traditional diet of the Inuit hunters of the far North.

Seals, walruses and polar bears are all what scientists like to call “ice obligate animals”: the ice sheet provides them with their preferred habitat. With the loss of the ice, new species are colonizing the Arctic, and those creatures that cannot now use the ice sheet have been forced to invade new habitats.

“Marine mammals can act as ecosystem sentinels because they respond to climate change through shifts in distribution, timing of their movements and feeding locations,” said Sue Moore of the U.S. National Oceanic and Atmospheric Administration. “These long-lived mammals also reflect changes to the ecosystem in their shifts in diet, body condition and physical health.”

Visit EcoWatch’s BIODIVERSITY and CLIMATE CHANGE pages for more related news on this topic.

 

Show Comments ()
Sponsored
Popular
Desperate for water, Puerto Ricans are resorting to any available sources, such as this stream in Cayey. Angel Valentin / NPR

Desperate Puerto Ricans Are Drinking Water From Hazardous Waste Sites

The ranking Democrat on the House Homeland Security Committee called for an investigation into the availability of potable water in Puerto Rico following reports Friday that residents are scrounging for water from hazardous waste sites.

After the U.S. Environmental Protection Agency (EPA) confirmed residents were trying to access water from three Superfund sites, and following a CNN story Friday featuring Puerto Ricans taking water from a fourth site, Rep. Bennie Thompson (D-MS) wrote a letter to acting DHS Secretary Elaine Duke asking if she knew about the situation and calling the reports "beyond disturbing."

Keep reading... Show less
Brant at Izembek Lagoon. Kristine Sowl / USFWS

Groups Slam Zinke's 'Backroom Deals' to Build Road Through Alaskan Wildlife Refuge

Ryan Zinke's Interior Department is working behind the scenes to build a controversial and long-contested road through the heart of Alaska's Izembek National Wildlife Refuge, documents show.

The refuge was established more than 30 years ago to conserve wetlands and habitats for migrating birds, brown bears and salmon and other wildlife. 300,000 of its 315,000 acres has been designated as Wilderness in 1980 under the Alaska National Interest Lands Conservation Act.

Keep reading... Show less
FAO / Giulio Piscitelli

On World Food Day, Pope Francis Says Link Between Climate Change and Hunger Is Undeniable

By Andrew McMaster

Speaking at the United Nations Food and Agriculture Organization (FAO) on World Food Day, Pope Francis addressed the need for governments around the world to acknowledge that climate change and migration were leading to increases in world hunger.

Francis received a standing ovation after a stirring speech in which he said all three issues were interrelated and require immediate attention.

Keep reading... Show less
The pallid bat is native to the western U.S., where the spread of white-nose syndrome is a threat. Ivan Kuzmin / Shutterstock

Why Are America's Bats Disappearing?

By John R. Platt

It's Friday evening in Pittsburgh, and the mosquitoes are out in force. One bites at my arm and I try to slap it away. Another takes the opportunity to land on my neck. I manage to shoo this one off before it tastes blood.

I'm at Carrie Furnaces, a massive historic ironworks on the banks of Pennsylvania's Monongahela River. Stories-tall rusting structures loom all around me, as do the occasional trees poking their way out of the ground. A tour guide, leading a group from the Society of Environmental Journalists conference, tells me the soil here is full of heavy metals and other pollutants from the factory, which operated for nearly a century before closing in 1982.

Keep reading... Show less
Sponsored
The Amur tiger is the extinct Caspian tiger's closest living relative. Mathias Appel / Flickr

After a Half-Century, Tigers May Return to Kazakhstan

Wild tigers may be on their way back to Kazakhstan.

This news is surprising for a few reasons. First, most people associate tigers with the jungles of India or Sumatra, even the snowy slopes of eastern Russia—not the dry landscapes of Central Asia. But Iran, Turkey and Kazakhstan were once home to thriving populations of Caspian tigers. Unfortunately, sometime between the 1940s and '70s, this subspecies went extinct due to widespread trapping, hunting, poisoning and habitat degradation.

Second, Kazakhstan isn't a nation that often comes up in conversations about conservation. In fact, if Americans recognize the world's largest landlocked nation for anything, it's probably the movie Borat.

Keep reading... Show less
www.youtube.com

California Wildfires: One of 'Greatest Tragedies' State Has Ever Faced

With aid from easing winds, the 11,000 firefighters beating back the Northern California wildfires are making "good progress," as the number of major blazes dropped to 15, the state's fire agency Cal Fire announced Sunday.

But as Cal Fire noted‚ "Sadly, the death toll has risen to 40 people."

Keep reading... Show less
Sponsored
Bonn Climate Change Conference, June 4 2015. UNclimatechange / Flickr.

UN Urges World Leaders to Heed Climate Risk, Warns of More Severe Disasters

By Paul Brown

The hurricanes and wildfires that have severely damaged large areas of the U.S. in recent weeks have had no impact on President Donald Trump's determination to ignore the perils of climate change and support the coal industry.

In a deliberate denial of mainstream science, the Trump administration has issued a strategic four-year plan for the U.S. Environment Protection Agency that does not once mention "greenhouse gas emissions," "carbon dioxide" or "climate change" in its 48 pages.

Keep reading... Show less
Popular
www.youtube.com

Oil Rig Explodes in Louisiana: 7 Injured, 1 Missing

An oil rig exploded on Lake Pontchartrain, Louisiana Sunday night, injuring seven crew members, with an eighth believed to be missing, authorities said.

The explosion was reported at 7:18 p.m. near St. Charles Parish and the city of Kenner. The platform, located in unincorporated Jefferson Parish, is owned by New Orleans-based Clovelly Oil Company.

Keep reading... Show less
Sponsored

mail-copy

Get EcoWatch in your inbox