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Toxic legacy

Laura Petersen
Special to The Union
On July 11, volunteers will post fish consumption advisories at local lakes and reservoirs.
Submitted photo |

Know & Go

What: Volunteer to post fish consumption advisories at local lakes and reservoirs

When: 9 a.m. to 5 p.m. Saturday, July 11

Who: The Sierra Fund, South Yuba River Citizens League, Wolf Creek Community Alliance

Conservation groups launch effort to post risks of mercury in fish

Up to 40 community volunteers are needed in July to help raise awareness about the dangers of eating fish taken from gold country lakes and streams.

The Sierra Fund, South Yuba River Citizens League and Wolf Creek Community Alliance are partnering on an event called “Post-It: Spread the word about what fish are safe to eat,” in an effort to fill a communication gap between anglers and information regarding healthy choices for eating locally caught fish.

From 9 a.m. to 5 p.m. Saturday, July 11 teams of volunteers will travel to local water bodies to post state-issued fish consumption advisories detailing safe eating guidelines for consuming fish.

The California EPA Environmental Justice Small Grants program awarded The Sierra Fund $19,699 to conduct the volunteer poster day and other work related to raising awareness of safe fish consumption.

“SYRCL is glad to partner with The Sierra Fund and Wolf Creek Community Alliance on this volunteer effort to help mobilize volunteers and increase the public’s understanding of how to safely consume fish from local lakes and reservoirs,” said Andrew

For more information: Contact Jenn Tamo at 530-265-5961 x201 or via email: jenn@syrcl.org.

How to volunteer: Register online at http://yubariver.org/volunteering/post-it/.

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For 60 years, fly fisherman Trent Pridemore has fished many lakes and streams dotting the Northern and Central Sierra Nevada, despite his awareness of an ever-present mercury risk.

Most of the time, Pridemore and fellow anglers in Gold Country Fly Fishers practice a conservation ethic known as catch-and-release, helping to ease pressures on this finite resource.

But on occasion, Pridemore who also loves a good meal, takes a fish home for dinner.

Earlier this week he ate a fish taken from Davis Lake near Portola and several times a year, when he fishes the Delta, he likes to keep one.

“I think the important thing is to be informed … I think most serious anglers are aware of the risks,” he said, but he wonders if the general public knows of the dangers.

With summer recreation season here, many families are loading the car with camping and fishing gear and heading to some of the most popular local fishing lakes — places like Rollins Reservoir, Bullards Bar and Scotts Flat — all heavily impacted by mercury from historic mining in the upstream watersheds.

A 2013 advisory from the California Office of Environmental Health Hazard Assessment (OEHHA), recommends that women aged 18 to 45 and children under 18 should choose wild-caught rainbow trout and smaller brown trout and avoid eating bass, carp, and larger brown trout.

For the advisory, scientists evaluated data from 272 California lakes and reservoirs and considered data from more than 2,600 individual fish samples.

The guidelines are intended to protect children and babies from mercury exposure, which can permanently damage their brain and nervous system.

Next month, in an effort to spread the word about fish-eating safety, The Sierra Fund is teaming up with South Yuba River Citizens League (SYRCL), Wolf Creek Community Alliance and 40 community volunteers to post signs highlighting state guidelines at 15 to 20 popular fishing locations in the region.

“We feel that providing this information in the Yuba watershed is significant due to the extensive mining history in the area which has impacted our local fish and reservoirs,” said Andrew Collins-Anderson, River People Coordinator with SYRCL.

Areas like Lake Wildwood, Scotts Flat, Bullards Bar, Lake Spaulding, Hell Hole, Oxbow, Slab Creek, Rollins, Combie, Englebright and Camp Far West will be targeted.

Since 2006, staff from The Sierra Fund have focused on the impacts of historic mining and since 2008 has worked to reach out to anglers.

Historic mining is the primary source of mercury in the Sierra. In the 1800s, mercury was mined from the California coast range and transported to the Sierra for use in the gold mines.

From these two sources — the gold mines in the Sierra and the mercury mines in the Coast range — mercury in the upper watersheds continues to be washed downstream contaminating today’s food chain.

“Rainbow trout is their best bet”

Since 2009, The Sierra Fund has interviewed 200 anglers fishing within a two hour drive of Grass Valley for a “Gold Country Angler Survey.”

Results indicate that the vast majority of people are consuming locally caught sport fish from mercury-contaminated waterways, some in amounts that exceed safe levels, and that they have limited understanding of the health hazards from eating those fish.

Of the people who reported eating the fish they catch, over half reported feeding the fish to children under 18 and women of childbearing age or pregnant.

The most popular fish eaten were bass and trout, a concern because bass and brown trout often have the highest levels of mercury.

“Mercury biomagnifies in the food chain when fish eat other fish. Therefore, fish that are at the top of the food chain — not bottom feeders — can have the highest levels of mercury,” said Carrie Monohan, Ph.D., The Sierra Fund’s Science Director.

“Bass, which are the top of the food chain in most Sierra foothill lakes, generally have the highest levels of mercury. Also, larger fish, that people like to catch to eat, have typically lived longer and can have higher mercury levels than younger fish of the same species,” she added.

Because brown trout eat other fish, they are higher on the food chain than rainbow trout and generally have higher mercury levels than rainbows of the same size.

“Fish species rather than location is the most important factor people should consider if they want lower mercury fish. Rainbow trout is their best bet,” said Monohan.

It could be another 10,000 years before the mercury in the Sierra is washed downstream, according to research published in 2013 by Dr. Michael Singer of University of St. Andrews in Scotland and a researcher from the Earth Research Institute at UC Santa Barbara.

Several regional projects are underway to remedy the local mercury problem.

The Sierra Fund is working on a long-term project at Malakoff Diggins State Historic Park to assess the amount of mercury that is coming out of the legacy mine site into the Yuba River; The U.S. Forest Service received funds to do a cleanup at the Relief Hill mine in the South Yuba Watershed and Nevada Irrigation District has a pilot project to remove sediment and mercury in Combie Reservoir.

“We hope that the cumulative benefits of these mercury remediation projects will eventually help to reduce mercury levels in all fish,” said The Sierra Fund’s Program Director Kerry Morse.

Learn more at: http://oehha.ca.gov/fish/special_reports/advisorylakesres.html, http://oehha.ca.gov/fish/general/broch.html, http://www.sierrafund.org.

Angler survey: http://sierrafund.org/mining/Angler_Survey_EXEC_SUMMARY.pdf

Or the full report: http://sierrafund.org/mining/Gold_Country_Angler_Survey.pdf

Contact freelance writer Laura Petersen at laurapetersen310@gmail.com or 530-913-3067.

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