Saving salmon means spreading risks among diverse populations, important new study says

Saving imperlied salmon in the Pacific Northwest means focusing a lot more on the genetic quality of the fish and a lot less on the quantity of fish cranked out in hatcheries, suggest the authors of a groundbreaking new study in the prestigious science journal Nature.

The notion that spawning lots of salmon in hatcheries could actually impede efforts to bring back struggling wild runs is not a new one. The science on that is solid. But the new study, which focused on the success of salmon runs in Alaska’s hatchery-less Bristol Bay, is “a game-changer,” according to the University of Washington team that produced the research.

Here’s why: The new study documents how Bristol Bay for more than half a century has consistently produced fishable sockeye salmon runs. That’s because in a natural system like Western Alaska, the existence of so many different runs that reproduce in different nooks and crannies of the ecosystem ensures that – whatever happens – some salmon runs will thrive. Runs that do well in cold, wet years are winners sometimes. Other times, when temperature and rainfall are relatively mild, runs better suited to those conditions will boom.

But every year, at least some runs will do well. It’s all about spreading out the risk.

Think of the varied salmon runs of Bristol Bay like a financial portfolio well-positioned to endure whatever goes down on Wall Street: stocks that take advantage of upturns, bonds that hold value in down times and maybe some real estate or pig belly futures or gold bullion thrown in for good measure.

Want to strike a blow on behalf of salmon for Earth Day? Get cracking on Corps' of Engineers rule change

If you want to strike a blow on behalf of imperiled salmon in honor of Earth Day, you better get cracking – there’s a deadline of Saturday to comment on a proposal by the U.S. Army Corps of Engineers that critics say would undermine efforts to bring back the icon of the Northwest. 

We’ll probably do a proper news story on this at some point, but there isn’t time for that before the comment deadline, so I’ll tell you what I’ve learned so far:

The Army Corps is responsible for the levees that are intended to keep rivers from spilling outside their banks, causing flooding. And the agency is pretty convinced it should prohibit any trees or even large bushes on the levees. The Corps claims – and this is apparently at the heart of the disagreement – that trees’ roots destabilize levees. People who want the trees left on the levees think just the opposite, that the roots help hold the levee soils together. The Corps admits the science is murky. 

Now, trees on levees are important to salmon for a number of reasons. Among them: Trees and bushes shade the waterways, keeping them cool, as salmon need. They also are home to bugs that fall in the water and are eaten by young salmon. And vegetation helps slurp up and filters polluted stormwater before it reaches the waterway.

The Corps, though, is proposing that plants and trees be chopped down once their trunks reach two inches in diameter.

This became something of a fixation for the Corps after the miserable performance of levees in and around New Orleans during Hurricane Katrina.

Doug Osterman is the guy who called this to our attention. He’s the Green-Duwamish-Central Puget Sound watershed coordinator for the King County government. The Corps’ rule against trees on levees led to toppling more than 1,000 of them already.

New study shows Roundup pesticide kills fish; U.S. heading toward OKing more 'Roundup-Ready' genetically engineered farm acreage

Roundup is one of the most widely used pesticides in the world. But it increases the incidence of disease in fish, a new study shows. And yet it looks like the government is about to greatly expand the U.S. acreage where it is applied by approving planting of vast swaths of genetically engineered alfalfa. These “Roundup-Ready” hayfields worry opponents of GE foods, and this latest news about the effect on fish is bound to stir the pot some more. (The opportunity for public comment on allowing GE alfalfa ends soon, btw.)

The new fish study, out of New Zealand, showed that when applied at recommended rates on fields near a freshwater stream, Roundup didn’t kill young freshwater fish outright. Score one point for Monsanto, Roundup’s manufacturer.

However, what Roundup did at this relatively dilute concentration was to increase the production of worm that’s a parasite of the fish, and comes from a particular snail. And the combination of more parasites and moderate levels of Roundup – aka “glyphosate” – produced what scientists called “significantly reduced fish survival.” They concluded:

"This is the first study to show that parasites and glyphosate can act synergistically on aquatic vertebrates at environmentally relevant concentrations, and that glyphosate might increase the risk of disease in fish. Our results have important implications when identifying risks to aquatic communities and suggest that threshold levels of glyphosate currently set by regulatory authorities do not adequately protect freshwater systems."

Intersex fish found across U.S. - which chemicals to blame?

The U.S. Geological Survey just completed a nine-year study in streams and rivers across the U.S. looking for intersex fish - males with female characteristics, like production of eggs, according toAlaska Dispatch. Largemouth and smallmouth bass were most affected, with 33 percent and 18 percent being intersex across the country, respectively. The full reportby Christopher Joyce is on NPR's All Things Considered.

Intersex fish aren't a new phenomenon, but this the largest study of its kind to be conducted in U.S. waters, according to the article. Scientists blame industrial and pharmaceutical chemicals, as well as personal care products like deodorant, cosmetics and shampoo. Many of these chemicals are "endocrine disruptors" that affect an individual's delicate hormone system.

We don't yet know if these chemicals are affecting humans. Many products containing them are not labeledin the United States, according to Samuel S. Epstein in the Huffington Post. It's difficult to isolate what is affecting other animals, since multiple chemicals could be mixing to form chemical cocktails.

The effects aren't restricted to fish. A resident in Montana has been tracking mutated jaws and genitals in deer and other animals for more than 13 years.

Hold the soap when washing the car

Washington officials are encouraging drivers to wash their cars over gravel or grass without soap in an effort to curb pollutants in runoff, according to Phuong Le of the Associated Press. Soap entering water systems through stormwater harms fish and other aquatic life, and even biodegradable soap still picks up pollutants like antifreeze, oil and metals. Those unwilling to shelve the soap can take their vehicles to local car washes, which filter the runoff before it reaches storm drains.

– Emily Linroth

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Desert fish loses 6-year legal fight

The Roundtail chub will have to wait its turn for protection under the Endangered Species Act. The U.S. Fish and Wildlife Service declined to add it to the endangered list, ending a  six-year battle with the Center for Biological Diversity, which says the chub has disappeared from 80 percent of its historic range below Glen Canyon Dam in Arizona and in western New Mexico.

The U.S. Fish and Wildlife Services said Tuesday, it would keep the fish on its candidate list along with more than 250 other plant and animal species. The AP's Susan Montoya Bryan has more here.