Wild salmon vulnerable to climate change, Science study reports

As if overfishing and habitat loss weren't threats enough for wild salmon, the imperiled fish are also vulnerable to climate change, suggests a new study in the 27 October issue of the international journal, Science.

Decomposing salmon carcasses have left behind a 300-year record of oceanic nitrogen in Alaskan lake bottoms, revealing population swings that seem to be related to known climate changes from this period.

Climate's impact on wild salmon has been uncertain, because existing population records were relatively short and complicated by the effects of fishing, dam-building, and other human activities.

"Traditionally, fisheries managers assumed the environment was constant when they calculated the maximum number of salmon that fishermen could harvest. But our study suggests a need for new, flexible management policies that take climate and lake nutrient levels into account," said lead Science author Bruce Finney of the University of Alaska-Fairbanks.

Finney and his colleagues delved beyond recent human influences by studying historical levels of the isotope nitrogen-15 in sediment core from lakes on Alaska's Kodiak island and near Bristol Bay.

In the ocean, salmon incorporate high levels of nitrogen-15 into their tissues. The isotope is only abundant in Alaska's coastal lakes if it's released from dead salmon that returned to the lake at the end of their lives to spawn. Lakes blocked off by waterfalls, for example, have lower levels of nitrogen-15.

Finney's team found several major fluctuations in nitrogen-15 levels over the last 300 years. These swings implied drops in the salmon population during the early 18th and 19th centuries, periods that were cooler than average, according to other studies cited in the Science paper.

The biggest salmon decline occurred in the 20th century, as human activities started to take effect.

The researchers also discovered a positive feedback effect that may be further

Contact: Ginger Pinholster
American Association for the Advancement of Science

Page: 1 2 3

Related biology news :

1. PNNL lands $10.3 million NIH biodefense contract to unlock proteomes of salmonella and pox
2. Flame retardant levels much higher in farmed salmon
3. Common worm provides insights into salmonella virulence
4. Policy review in Science calls for Bush Administration to protect wild salmon
5. Aquatic scientists divided on role of sea lice from salmon farms in decline of native salmon in B.C.
6. Farmed salmon more toxic than wild salmon, study finds
7. New book says Northwest salmon could face same fate as those in Northeast, England
8. UVa scientists detail salmonella protein
9. Researchers measure effects of flow regulation and diking on salmon habitat loss
10. Salmon farms pose significant threat to salmon fisheries in the Pacific Northwest, researchers find
11. Threatened juvenile salmon get scientific assistance

Post Your Comments:

(Date:5/6/2017)... , May 5, 2017 ... just announced a new breakthrough in biometric authentication ... exploits quantum mechanical properties to perform biometric authentication. These ... smart semiconductor material created by Ram Group and ... finance, entertainment, transportation, supply chains and security. Ram ...
(Date:4/19/2017)... New York , April 19, 2017 ... competitive, as its vendor landscape is marked by the ... the market is however held by five major players ... Safran. Together these companies accounted for nearly 61% of ... of the leading companies in the global military biometrics ...
(Date:4/17/2017)... 17, 2017 NXT-ID, Inc. (NASDAQ: NXTD ... filing of its 2016 Annual Report on Form 10-K on Thursday ... ... available in the Investor Relations section of the Company,s website at ... website at http://www.sec.gov . 2016 Year Highlights: ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... (PRWEB) , ... October 12, ... ... ) has launched Rosalind™, the first-ever genomics analysis platform specifically designed for ... complexity. Named in honor of pioneering researcher Rosalind Franklin, who made a ...
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... pathology, announced today it will be hosting a Webinar titled, “Pathology is going ... Pathology Associates , on digital pathology adoption best practices and how Proscia improves ...
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... Administration (FDA) has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal ... the treatment of osteosarcoma. SBT-100 is able to cross the cell membrane and ...
(Date:10/10/2017)... , Oct. 10, 2017 International research firm Parks Associates ... will speak at the TMA 2017 Annual Meeting , October 11 ... in the residential home security market and how smart safety and security ... Parks Associates: ... "The residential security ...
Breaking Biology Technology:
Cached News: