Navigation Links
Predictions of climate impacts on fisheries can be a mirage
Date:3/25/2013

In the early 1940s, California fishermen hauled in a historic bounty of sardine at a time that set the backdrop for John Steinbeck's "Cannery Row" novel. But by the end of the decade the nets came up empty and the fishery collapsed. Where did they all go? According to a new study led by scientists at Scripps Institution of Oceanography at UC San Diego, the forces behind the sardine mystery are a dynamic and interconnected moving target.

Publishing in the Proceedings of the National Academy of Sciences, Scripps graduate student Ethan Deyle, professor George Sugihara, and their colleagues argue that problems lie in seeking answers one factor at a time, as scientists have done for decades. What is the impact of climate on sardines? What is the effect of overfishing on sardines? Focusing on single variables in isolation can lead to misguided conclusions, the researchers say.

"Studying ecosystems in this piecemeal way makes it hard to find quantitative relationships, the kind that are useful for management and stand the test of time," said Deyle.

Instead, using novel mathematical methods developed last year at Scripps, the researchers argue that climate, human actions, and ecosystem fluctuations combine to influence sardine and other species populations, and therefore such factors should not be evaluated independently.

The technique developed by Sugihara and his colleagues, called "convergent cross mapping," takes multiple variables into account and avoids the centuries-old "correlation does not imply causation" issue that has plagued single-factor studies (see: http://scrippsnews.ucsd.edu/Releases/?releaseID=1292). For example, based on data from the Scripps Institution of Oceanography Pier, studies in the 1990s showed that higher temperatures are beneficial for sardine production. By 2010 new studies proved that the temperature correlation was instead a misleading, or "mirage," determination.

"Mirages are associations among variables that spontaneously come and go or even switch sign, positive or negative," said Sugihara. "Ecosystems are particularly perverse on this issue. The problem is that this kind of system is prone to producing mirages and conceptual sand traps, continually causing us to rethink relationships we thought we understood."

By contrast, convergent cross mapping avoids the mirage issue by seeking evidence from dynamic linkages between factors, rather than one-to-one statistical correlations.

"Sustainable sardine fishing based on ecosystem-based management should adapt to dynamic changes in the ocean environment, and future policies should incorporate these effects to avoid another 'cannery row,'" said Deyle.


'/>"/>

Contact: Mario Aguilera or Robert Monroe
scrippsnews@ucsd.edu
858-534-3624
University of California - San Diego
Source:Eurekalert

Related biology news :

1. New method for greenhouse gas predictions
2. New Antarctic geological timeline aids future sea-level predictions
3. Missing polar weather systems could impact climate predictions
4. NOAA: Gulf of Mexico dead zone predictions feature uncertainty
5. Living in a sunny climate does not improve vitamin D levels in hip fracture patients
6. Dinosaur-era climate change study suggests reasons for turtle disappearance
7. Nevada climate, environmental data network to inform research, community
8. International conference to tackle climate-change threats to agriculture
9. Climate-smart strategies proposed for spectacular US-Canadian landscape
10. A game plan for climate change
11. March of the pathogens: Parasite metabolism can foretell disease ranges under climate change
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/26/2016)... BANGALORE, India and LONDON ... Infosys Finacle, part of EdgeVerve Systems, a ... ), and Onegini today announced a partnership to ... banking solutions.      (Logo: http://photos.prnewswire.com/prnh/20151104/283829LOGO ... banks to provide their customers enhanced security to ...
(Date:4/15/2016)... -- A new partnership announced today will help life ... a fraction of the time it takes today, ... insurance policies to consumers without requiring inconvenient and ... rapid testing (A1C, Cotinine and HIV) and higi,s ... pulse, BMI, and activity data) available at local ...
(Date:4/13/2016)... -- IMPOWER physicians supporting Medicaid patients in Central ... in telehealth thanks to a new partnership with higi. ... patients can routinely track key health measurements, such as ... when they opt in, share them with IMPOWER clinicians ... retail location at no cost. By leveraging this data, ...
Breaking Biology News(10 mins):
(Date:4/29/2016)... Diego, CA (PRWEB) , ... April 29, 2016 , ... ... Foundation (NSCF) to support the development of a patient-specific stem cell therapy for the ... in the lab of Dr. Jeanne Loring at The Scripps Research Institute in San ...
(Date:4/28/2016)... ... April 28, 2016 , ... Connecticut Innovations ... growing companies, today announced the launch of VentureClash , a $5 million ... , “VentureClash looks to attract the best early-stage companies here in Connecticut, ...
(Date:4/27/2016)... ... ... Shimadzu Scientific Instruments (SSI) will be showcasing a broad ... Expo. Shimadzu’s high-performance instruments enable laboratories to test cannabis products for potency, moisture, ... booth 1021 to learn how Shimadzu’s instruments can help improve QA/QC testing, peak ...
(Date:4/27/2016)... ... April 27, 2016 , ... The ... announce the appointment of John Tilton as Chief Commercial Officer.  Mr. Tilton joined ... of the founding commercial leaders responsible for the commercialization of multiple orphan drug ...
Breaking Biology Technology: