ملف:Lamprey in the Sandy River Basin (27067997756).jpg

محتويات الصفحة غير مدعومة بلغات أخرى.
من ويكيبيديا، الموسوعة الحرة

الملف الأصلي(1٬920 × 1٬080 بكسل حجم الملف: 166 كيلوبايت، نوع MIME: image/jpeg)

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It is a small miracle every time an adult steelhead returns from the Pacific Ocean to lay its eggs in the Sandy River Basin.

Their 2,000-mile journey takes 2 years to accomplish, and only recently have fish biologists started fixing spawning habitat to increase the numbers game of miracle steelhead eggs.

The Lower Columbia River Steelhead was listed as a threatened species under the Endangered Species Act in 1998, a status that was reaffirmed in 2006.

In 2007, BLM partner agencies like the U.S. Forest Service and the Freshwater Trust began fixing decades of human river manipulation, returning the ecosystem to its more natural state. This included removing two dams in the Sandy Basin, demolishing river berms and putting log jams at strategic points to increase water flow to vital side channels, where steelhead like to lay eggs.

For several years now, Bruce Zoellick—fish biologist for the Bureau of Land Management—has been doing practically everything he could to restore habitat for the threatened steelhead. That even means snorkeling underwater to count juvenile fish.

The results have been encouraging, to say the least.

“I’m so excited about steelhead because it’s a great response — but it’s also my favorite fish,” said Zoellick after a river survey last month.

Since 2012, Zoellick has been closely monitoring a particular 2-mile stretch of the Salmon River, a primary tributary for the Sandy, maneuvering all the side channels to count steelhead redds, or nests in the gravel where fish lay eggs.

In 2012, 64 redds were counted in that stretch of river. Only two years later that number had almost doubled to 115 redds. And in 2016, for surveys that just finished in May, the total was 137, something that Zoellick excitably calls a “world record.”

“We reconnected those side channels and got a really good response from the fish,” said Zoellick, who added that numbers for coho salmon and lamprey are also positive.

The increasing number of redds could equate to 3,000 or 4,000 returning adult steelhead next year, said Zoellick, a high enough rate to compare favorably with steelhead streams in the coast range, which is a much shorter freshwater commute to the ocean.

Mark McCollister, habitat restoration director for the Freshwater Trust, called the latest fish levels excellent, encouraging and validating, adding that future work on the Sandy could “drive recovery of the entire lower Columbia basin.”

“We might actually move that dial closer to recovery,” said McCollister in reference to threatened fish species.

And that would be another small miracle.

--story by Toshio Suzuki, BLM: tsuzuki@BLM.gov

--video captured in the Salmon River in April of 2016 by Bruce Zoellick, BLM
التاريخ
المصدر Lamprey in the Sandy River Basin
المؤلف Bureau of Land Management Oregon and Washington from Portland, America

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نَشَر BLMOregon هذه الصُّورة على موقع فلِيكر بتاريخ https://flickr.com/photos/50169152@N06/27067997756 (أَرشيف). ورَاجَعها FlickreviewR 2 في ١٢ مايو ٢٠١٨، وتأكَّدَ أَنَّها مُرخَّصة برخصة cc-by-2.0.

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Public domain This image is a work of a Bureau of Land Management* employee, taken or made as part of that person's official duties. As a work of the U.S. federal government, the image is in the public domain in the United States.
*or predecessor organization

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