Preview of the 2012 Eastern Bering Sea Pollock Stock Assessment

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Portion of “Fishes of the Salish Sea” mural by Ray Troll ©2011

Washington Sea Grant, the School of Aquatic and Fishery Sciences (SAFS), and the University of Washington College of the Environment invite you to attend a preview of this year’s assessment for
Eastern Bering Sea (EBS) pollock — the target of one of the world’s largest fisheries. The purpose of this forum is to provide fishery stakeholders and the public the opportunity to learn about the status of the EBS pollock stock and to ask questions and discuss the science underlying the assessment. Dr. James Ianelli, NMFS Alaska Fishery Science Center scientist and SAFS affiliate professor, will present the EBS pollock assessment model and the most recent assessment of trends in the EBS pollock stock, including the recommended ABC (Allowable Biological Catch) for the fishery in 2013. A reception will follow. We regret that the meeting room lacks teleconferencing capability.

Date: November 7, 2012
Preview: 4:00 to 5:30 p.m.
Reception: 5:30 to 6:30 p.m.
Where: Fishery Sciences Building
University of Washington, 1122 N.E. Boat Street, Room 102 (Auditorium)

Parking is available in a pay lot on the west side of the building, and limited metered parking is available on Boat Street.

For more information, please contact Ed Melvin, Washington Sea Grant, edmelvin@uw.edu or 206 543 9968.

Impacts of ocean acidification on marine seafood.

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Impacts of ocean acidification on marine seafood.

Trends Ecol Evol. 2012 Nov 1;

Authors: Branch TA, Dejoseph BM, Ray LJ, Wagner CA

Abstract
Ocean acidification is a series of chemical reactions due to increased CO(2) emissions. The resulting lower pH impairs the senses of reef fishes and reduces their survival, and might similarly impact commercially targeted fishes that produce most of the seafood eaten by humans. Shelled molluscs will also be negatively affected, whereas cephalopods and crustaceans will remain largely unscathed. Habitat changes will reduce seafood production from coral reefs, but increase production from seagrass and seaweed. Overall effects of ocean acidification on primary productivity and, hence, on food webs will result in hard-to-predict winners and losers. Although adaptation, parental effects, and evolution can mitigate some effects of ocean acidification, future seafood platters will look rather different unless CO(2) emissions are curbed.

PMID: 23122878 [PubMed – as supplied by publisher]

via pubmed: school of aquatic an… http://www.ncbi.nlm.nih.gov/PubMed/23122878?dopt=Abstract

Elevated pCO2 causes developmental delay in early larval Pacific oysters

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The paper, “Elevated pCO2 causes developmental delay in early larval Pacific oysters, Crassostrea gigas“, is included in an upcoming special issue on ocean acidification in the journal Marine Biology.  I did the research  in Emily Carrington’s lab in Friday Harbor during the summer of 2011 with the help of researcher Michael “Moose” O’Donnell.  Other co-authors and contributors are SAFS professors Carolyn Friedman and Steven Roberts.  Our research shows that elevated pCO2, an environmental condition that results from both natural (respiration, upwelling) and unnatural (emissions) processes, causes a developmental delay in oyster larvae.  This delay could have ecological implications for larval development and possibly influence later life stages.

 

 

Trade-offs in the design of fishery closures: management of silky shark bycatch in the eastern Pacific Ocean tuna fishery.

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Related Articles

Trade-offs in the design of fishery closures: management of silky shark bycatch in the eastern Pacific Ocean tuna fishery.

Conserv Biol. 2009 Jun;23(3):626-35

Authors: Watson JT, Essington TE, Lennert-Cody CE, Hall MA

Abstract
Bycatch–the incidental catch of nontarget species–is a principal concern in marine conservation and fisheries management. In the eastern Pacific Ocean tuna fishery, a large fraction of nonmammal bycatch is captured by purse-seine gear when nets are deployed around floating objects. We examined the spatial distribution of a dominant species in this fishery’s bycatch, the apex predator silky shark (Carcharhinus falciformis), from 1994 to 2005 to determine whether spatial closures, areas where fishing is prohibited, might effectively reduce the bycatch of this species. We then identified candidate locations for fishery closures that specifically considered the trade-off between bycatch reduction and the loss of tuna catch and evaluated ancillary conservation benefits to less commonly captured taxa. Smoothed spatial distributions of silky shark bycatch did not indicate persistent small areas of especially high bycatch for any size class of shark over the 12-year period. Nevertheless, bycatch of small silky sharks (<90 cm total length) was consistently higher north of the equator during all years. On the basis of this distribution, we evaluated nearly 100 candidate closure areas between 5°N and 15°N that could have reduced, by as much as 33%, the total silky shark bycatch while compromising only 12% of the tuna catch. Although silky sharks are the predominant species of elasmobranchs caught as bycatch in this fishery, closures also suggested reductions in the bycatch of other vulnerable taxa, including other shark species and turtles. Our technique provides an effective method with which to balance the costs and benefits of conservation in fisheries management. Spatial closures are a viable management tool, but implementation should be preceded by careful consideration of the consequences of fishing reallocation.

PMID: 19040650 [PubMed – indexed for MEDLINE]

via pubmed: school of aquatic an… http://www.ncbi.nlm.nih.gov/PubMed/19040650?dopt=Abstract

Synchronous Cycling of Ichthyophoniasis with Chinook Salmon Density Revealed during the Annual Yukon River Spawning Migration

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Synchronous Cycling of Ichthyophoniasis with Chinook Salmon Density Revealed during the Annual Yukon River Spawning Migration

Transactions of the American Fisheries Society, Volume 141, Issue 3, 2012
May 4, 2012

by Stanley Zuray, Richard Kocan & Paul Hershberger

Abstract
Populations of Chinook salmon Oncorhynchus tshawytscha in the Yukon River declined by more than 57% between 2003 and 2010, probably the result of a combination of anthropogenic and environmental factors. One possible contributor to this decline is Ichthyophonus, a mesomycetozoan parasite that has previously been implicated in significant losses of fish, including Chinook salmon. A multiyear epidemiological study of ichthyophoniasis in the Yukon River revealed that disease prevalence and Chinook salmon population abundance increased and decreased simultaneously (i.e., were concordant) from 1999 to 2010. The two values rose and fell synchronously 91% of the time for female Chinook salmon and 82% of the time for males; however, there was no significant correlation between Ichthyophonus prevalence and population abundance. This synchronicity might be explained by a single factor, such as a prey item that is critical to Chinook salmon survival as well as a source of Ichthyophonus infection. The host–parasite relationship between Ichthyophonus and migrating Chinook salmon from 2004 to 2010 was similar to that reported for the previous 5 years. During 2004–2010, overall disease prevalence was significantly higher among females (21%) than among males (8%), increased linearly with fish length for both males and females, and increased in both sexes as the fish progressed upriver. These regularly occurring features of host–parasite dynamics confirm a stable base of transmission for Ichthyophonus. However, from 2003 to 2010, disease prevalence decreased from 30% to just 8% in males and from 45% to 9% in females, paralleling a similar decline in Chinook salmon abundance during the same period. These findings may help clarify questions regarding the complex host–parasite dynamics that occur in marine species such as herrings Clupea spp., which have less well-defined population structures.

Full version

Pattern and process of biotic homogenization in the New Pangaea.

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Pattern and process of biotic homogenization in the New Pangaea.

Proc Biol Sci. 2012 Oct 10;

Authors: Baiser B, Olden JD, Record S, Lockwood JL, McKinney ML

Abstract
Human activities have reorganized the earth’s biota resulting in spatially disparate locales becoming more or less similar in species composition over time through the processes of biotic homogenization and biotic differentiation, respectively. Despite mounting evidence suggesting that this process may be widespread in both aquatic and terrestrial systems, past studies have predominantly focused on single taxonomic groups at a single spatial scale. Furthermore, change in pairwise similarity is itself dependent on two distinct processes, spatial turnover in species composition and changes in gradients of species richness. Most past research has failed to disentangle the effect of these two mechanisms on homogenization patterns. Here, we use recent statistical advances and collate a global database of homogenization studies (20 studies, 50 datasets) to provide the first global investigation of the homogenization process across major faunal and floral groups and elucidate the relative role of changes in species richness and turnover. We found evidence of homogenization (change in similarity ranging from -0.02 to 0.09) across nearly all taxonomic groups, spatial extent and grain sizes. Partitioning of change in pairwise similarity shows that overall change in community similarity is driven by changes in species richness. Our results show that biotic homogenization is truly a global phenomenon and put into question many of the ecological mechanisms invoked in previous studies to explain patterns of homogenization.

PMID: 23055062 [PubMed – as supplied by publisher]

via pubmed: school of aquatic an… http://www.ncbi.nlm.nih.gov/PubMed/23055062?dopt=Abstract

FISH441 Class Research Published

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In this month’s issue of the Journal of Shellfish Research, results from a research project carried out in the lab section of FISH441: Integrative Environmental Physiology was published. David Metzger and Paul Pratt (now both SAFS alum) are primary authors on the paper entitled: Characterizing the Effects of Heavy Metal and Vibrio Exposure on Hsp70 Expression in Crassostrea gigas Gill Tissue.

From the abstract:

In this study, oysters were exposed to copper and the bacterium Vibrio tubiashii to characterize how these environmental stressors influence Hsp70 gene and protein expression. Bacterial exposure did not affect Hsp70 expression, whereas copper exposure changed both transcript and protein levels significantly. Interestingly, copper exposure increased gene expression and decreased protein levels when compared with controls. The dynamics of Hsp70 regulation observed here provide important insight into heavy metal exposure and heat shock protein levels in oysters, highlighting considerations that should be made when using Hsp70 as an indicator of an organism’s general stress response.

 

Read the entire article 

This was one of the 5 most read papers in JSR for the month of September!

A Dark Cloud and a Silver Lining for the World’s Fisheries

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SAFS Professor Ray Hilborn was co-author of “a new study [revealing] that small, unassessed fisheries are in even worse shape than we thought. But the research also provides hope that smarter management could stop the bleeding—and provide more sustainable seafood.”

Characterizing short read sequencing for gene discovery and RNA-Seq analysis in Crassostrea gigas.

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Characterizing short read sequencing for gene discovery and RNA-Seq analysis in Crassostrea gigas.

Comp Biochem Physiol Part D Genomics Proteomics. 2012 Jun;7(2):94-9

Authors: Gavery MR, Roberts SB

Abstract
Advances in DNA sequencing technology have provided opportunities to produce new transcriptomic resources for species that lack completely sequenced genomes. However, there are limited examples that rely solely on ultra-short read sequencing technologies (e.g. Solexa, SOLiD) for transcript discovery and gene expression analysis (i.e. RNA-Seq). Here we use SOLiD sequencing to examine gene expression patterns in Pacific oyster (Crassostrea gigas) populations exposed to varying degrees of anthropogenic impact. Novel transcripts were identified and RNA-Seq analysis revealed several hundred differentially expressed genes. Gene enrichment analysis determined that in addition to biological processes predicted to be associated with anthropogenic influences (e.g. immune response), other processes play important roles including cell recognition and cell adhesion. To evaluate the effectiveness of restricting characterization solely to short read sequences, mapping and RNA-Seq analysis were also performed using publicly available transcriptome sequence data as a scaffold. This study demonstrates that ultra-short read sequencing technologies can effectively generate novel transcriptome information, identify differentially expressed genes, and will be important for examining environmental physiology of non-model organisms.

PMID: 22244882 [PubMed – indexed for MEDLINE]

via pubmed: school of aquatic an… http://www.ncbi.nlm.nih.gov/PubMed/22244882?dopt=Abstract

WA Cooperative Fish & Wildlife Research Unit Annual Student Presentations

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The Washington Cooperative Fish & Wildlife Research Unit will be celebrating its 45th Anniversary and hosting its annual student presentation this Thursday, Sept. 27. The event will have a great line-up of student presentations–something for everyone.  Students will be competing for the Gilbert and Pat Pauley Award for best presentation.

A Keynote Address will be given by Dr. Brian Kertson, a recent Unit graduate and the Large Carnivore Specialist for the Washington Department of Fish and Wildlife. Lunch will be provided as a social hour and dinner.  There will be a poster session as part of the meeting.  The Co-op is fortunate to have Vasily Baranyuk visiting from Russia.  Vasily is the leading authority on Wrangel Island Snow Geese and will be displaying photographs taken during his 30 years of research on the geese.

What: WA Cooperative Fish & Wildlife Research Unit Annual Student Presentations and 45th Anniversary Celebration
When: Thursday, September 27, from 8 Am to 6 PM
Where:  Center for Urban Horticulture, 3501 NE 41st Street, Seattle, WA 98195

If you plan to attend, please RSVP to Verna Blackhurst: vernab at uw.edu.