After long decline, mercury increasing in Great Lakes fish such as walleye, trout

After long decline, mercury increasing in Great Lakes fish such as walleye, trout

By Keith Matheny

Source: Detroit Free Pres

4/9/2017

$Keith Matheny$

By Keith Matheny, Detroit Free Press
Posted Apr 9, 2017 at 5:00 AM

DETROIT — It’s not supposed to be like this.

Although advisories about toxic mercury in fish have continued in the Great Lakes, with recommendations to limit consumption of certain species to a few times per month, the amount of mercury found in fish tissues has dropped steadily over decades since the 1970s.

That corresponded with the reduction of pollution coming from Midwestern smokestacks as regulations tightened, pollution-prevention technology improved and coal-fired factories and power plants went offline.

But over the past several years, the decline has reversed. Scientists are finding mercury levels rising in large Great Lakes fish such as walleye and lake trout. Curiously, it’s occurring in fish in some locations but not others. Researchers are trying to figure out why.

The mercury levels are not surpassing U.S. Environmental Protection Agency thresholds, but researchers want to determine whether what they are seeing is temporary or a trend that will worsen.

The answer has large ramifications for the Great Lakes’ sports-fishing industry.

Mercury is a heavy, silvery metal, unusual in that it’s liquid at room temperature. It’s naturally occurring, but is rare to find uncombined with other elements.

Walleye

Continue...

News Id		Source	Stamp	country
4726	Climate Change has Surprising Effect on Endangered Naked Carp; 'Metabolic Holiday'	Underwatertimes	2006-12-19	US
4727	Snakeheads Appear at Home in the Potomac	washington post	2006-10-02	US
4728	Farming endangered blue-fin tuna	bbc news	2006-12-27	JP
4729	World First as Endangered Fish Population Recovers; Shortnose Sturgeon Numbers Up 400%	Underwatertimes	2007-02-06	US
4730	Chips plan to keep an eye on fish	bbc news	2006-10-16	CA
4731	Scientists: First Documented Spawning of White Fish in the Detroit River Since 1900s	underwatertimes	2006-10-17	US
4732	Study: Critical Nutrients in Ecosystems Change when Fish Become Extinct	underwatertimes	2007-03-27	CA
4733	'No debate' that fish farms kill wild salmon, says B.C. scientist	CBC News	2006-10-20	CA
4734	A Swarm of Biologically-inspired Little Underwater Explorers	harvard	2021-01-15	US
4735	Scientists discover electric eels hunting in a group	Smithsonian	2021-01-14	BZ
4736	Robot fish equipped with tiny cameras could change ocean rescues	ctvnews	2021-01-13	CA
4737	The B.C. fish you've likely never heard of that's confounding trawlers and officials	CBC News	2021-01-03	US
4738	Thai Fishermen Break Ranks, Vow to Resume Hunt of Endangered Mekong Catfish; 'We Need to Make A Living'	underwatertimes	2006-03-04	TH
4739	Despite rescue effort, Maine salmon may be facing extinction	underwatertimes	2006-01-31	CA
4740	One fish, two fish: New sensor improves fish counts	underwatertimes	2006-02-02	US
4741	Scientists: Evolutionary Origin of Fins, Limbs Discovered; 'This Confirms a Lovely Idea'	underwatertimes	2006-07-26	US
4742	Study: Great Lakes' Salmon Failing To Thrive Because of 'Junk Food' Diet	Underwatertimes	2006-05-21	US
4743	Warming Swiss rivers threaten fish stocks	swissinfo	2020-12-31	CH
4744	European chub named Fish of the Year	swissinfo	2021-01-02	CH
4745	First as Brit Pair's Carp Conquers Japanese Koi Show; 'Our Fish is Superb'	Underwatertimes	2006-02-04	UK
4746	Researcher: 'Two-Mouthed' Trout Caused by Injury, Not Genetics	underwatertimes	2006-02-08	US
4747	Biologists dispute fish farm study that says farmed salmon can coexist with real salmon	alaskareport	2006-08-03	CA
4748	Study: Protein Myglobin Key to Common Carp's Ability to Survive with Little Oxygen	Underwatertimes	2006-06-01	UK
4749	Skipper nets 'miracle' swordfish	bbc	2006-08-08	UK
4750	Consumer Reports: Pregnant Women Should Not Eat Canned Tuna; 'It's Prudent'	Underwatertimes	2006-06-05	US

189 of [217 - pages.]