27 research outputs found
Humpback whales feed on hatchery-released juvenile salmon
Thank you to staff and managers at NSRAA, Armstrong Keta Inc. and NOAA for collecting data daily during their release seasons. Bart Watson collaborated in study design. Thank you to Elena McCauley, R. Katy Pendell and Margaret Schoenfeld for data entry.Humpback whales are remarkable for the behavioural plasticity of their feeding tactics and the diversity of their diets. Within the last decade at hatchery release sites in Southeast Alaska, humpback whales have begun exploiting juvenile salmon, a previously undocumented prey. The anthropogenic source of these salmon and their important contribution to local fisheries makes the emergence of humpback whale predation a concern for the Southeast Alaska economy. Here, we describe the frequency of observing humpback whales, examine the role of temporal and spatial variables affecting the probability of sighting humpback whales and describe prey capture
behaviours at five hatchery release sites. We coordinated twice daily 15 min observations during the spring release seasons 2010–2015. Using logistic regression, we determined that the probability of occurrence of humpback whales increased after releases began and decreased after releases concluded. The probability of whale occurrence varied among release sites but did not increase significantly over the 6 year study period. Whales were reported to be feeding on juvenile chum, Chinook
and coho salmon, with photographic and video records of whales feeding on coho salmon. The ability to adapt to new prey sources may be key to sustaining their population in a changing ocean.Ye
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Potentially adaptive mitochondrial haplotypes as a tool to identify divergent nuclear loci
1. Genetic tools are commonly used for conservation and management of at-risk species. Individuals are often sampled from mixtures that are composed of many populations, which creates a need to assign individuals to their source. This can be problematic when the genetic divergence among source populations is weak but can be improved using adaptive genetic loci, which should show stronger levels of divergence.
2. We previously reported a signature of positive selection in the mitochondrial-encoded ND5 subunit of complex I in diverse taxa. The respiratory machinery of the mitochondria in salmonids is composed of more than 80 nuclear genes and there is substantial interaction between nuclear and mitochondrial expressed gene products. Recent studies report adaptive variation in mitochondrial function as well as co-evolution between mitochondrial and nuclear genomes. We used potentially adaptive ND5-based mitochondrial haplotypes to identify nuclear loci that would display increased levels of genetic divergence compared to neutral nuclear loci in chum salmon (Oncorhynchus keta). Populations in a geographic area the size of France have previously demonstrated weak genetic divergence even after substantial discovery efforts by multiple laboratories for allozymes, microsatellites and SNPs over the last two decades.
3. We used RAD-based next-generation sequencing and identified a nuclear-encoded subunit of mitochondrial complex I that was a significant FST outlier and 14 other divergent nuclear markers that improve genetic assignment of individuals to their population of origin relative to assignments based on neutral markers alone.
4. This work demonstrates how a known adaptive marker can be leveraged to increase the probability of identifying divergent markers for applied genetics tools that may be biologically linked to it
Sheep Updates 2008 - part 3
This session covers fiveteen papers from different authors:
CONTROLLING FLY STRIKE
1. Breeding for Blowfly Resistance - Indicatoe Traits, LJE Karlsson, JC Greeff, L Slocombe, Department of Agriculture & Food, Western Australia
2.A practical method to select for breech strike resistance in non-pedigreed Merino flocks, LJE Karlsson, JC Greeff, L Slocombe, K. Jones, N. Underwood, Department of Agriculture & Food, Western Australia
3. Twice a year shearing - no mulesing, Fred Wilkinson, Producer, Brookton WA
BEEF
4. Commercial testing of a new tool for prediction of fatness in beef cattle, WD HoffmanA, WA McKiernanA, VH OddyB, MJ McPheeA, Cooperative Research Centre for Beef Genetic Technologies, A N.S.W. Deptartment of Primary Industries, B University of New England
5. A new tool for the prediction of fatness in beef cattle, W.A. McKiernanA, V.H. OddyB and M.J. McPheeC; Cooperative Research Centre for Beef Genetic Technologies, A N.S.W. Dept of Primary Industries, B University of New England, C N.S.W. Dept of Primary Industries Beef Industry Centre of Excellence.
6. Effect of gene markers for tenderness on eating quality of beef, B.L. McIntyre, CRC for Beef Genetic Technologies, Department of Agriculture and Food WA
7. Accelerating beef industry innovation through Beef Profit Partnerships, Parnell PF1,2, Clark RA1,3, Timms J1,3, Griffith G1,2, Alford A1,2, Mulholland C1 and Hyland P1,4,1Co-operative Research Centre for Beef Genetic Technologies; 2NSW Department of Primary Industries; 3 Qld Department of Primary Industries and Fisheries; 4The University of Queensland.
SUSTAINABILITY
8. The WA Sheep Industry - is it ethically and environmentally sustainable? Danielle England, Department of Agriculture and Food Western Australia
9. Overview of ruminant agriculture and greenhouse emissions, Fiona Jones, Department of Agriculture and Food Western Australia
10. Grazing for Nitrogen Efficiency, John Lucey, Martin Staines and Richard Morris, Department of Agriculture and Food Western Australia
11. Investigating potential adaptations to climate change for low rainfall farming system, Megan Abrahams, Caroline Peek, Dennis Van Gool, Daniel Gardiner, Kari-Lee Falconer, Department of Agriculture and Food Western Australia
SHEEP
12. Benchmarking ewe productivity through on-farm genetic comparisons, Sandra Prosser, Mario D’Antuono and Johan Greeff; Department of Agriculture and Food Western Australia
13. Increasing profitability by pregnancy scanning ewes, John Young1, Andrew Thompson2 and Chris Oldham2; 1Farming Systems Analysis Service, Kojonup, WA, 2Department of Agriculture and Food Western Australia
14. Targeted treatment of worm-affected sheep - more efficient, more sustainable, Brown Besier, Department of Agriculture and Food Western Australia
15. Improving Weaner Sheep Survival, Angus Campbell and Ralph Behrendt, Cooperative Research Centre for Sheep Industry Innovatio
Sheep Updates 2007 - part 4
This session covers eight papers from different authors:
GRAZING
1. The impact of high dietary salt and its implications for the management of livestock grazing saline land, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence and David Masters, CRC for Plant-based Management of Dryland Salinity, Faculty of Natural & Agricultural Sciences, The University of Western Australia, WA.
2. Sustainable Grazing on Saline Lands - outcomes from the WA1 research project, H.C. Norman1,2, D.G. Masters1,2, R. Silberstein1,2, F. Byrne2,3, P.G.H. Nichols2,4, J. Young3, L. Atkins1,2, M.G. Wilmot1,2, A.J. Rintoul1,2, T. Lambert1,2, D.R. McClements2,4, P. Raper4, P. Ward1,2, C. Walton5 and T. York6 1CSIRO Centre for Environment and Life Sciences, Wembley, WA 2CRC for Plant-based Management of Dryland Salinity. 3School of Agricultural and Resource Economics, University of Western Australia. 4Department of Agriculture and Food WA. 5Condering Hills, Yealering. 6Anameka Farms, Tammin.
MEAT QUALITY
3. Development of intramuscular fat in prime lambs, young sheep and beef cattle, David Pethick1, David Hopkins2 and Malcolm McPhee3,1School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA, 2NSW Department of Primary Industries, Cowra, NSW,3NSW Dept. of Primary Industries, University of New England, Armidale, NSW,
4. Importance of drinking water temperature for managing heat stress in sheep, Savage DB, Nolan JV, Godwin IR, Aoetpah A, Nguyen T, Baillie N and Lawler C University of New England, Armidale, NSW, Australia
EWE MANAGEMENT TOOLS
5. E - sheep Management of Pregnant Merino Ewes and their Finishing Lambs, Ken GeentyA, John SmithA, Darryl SmithB, Tim DyallA and Grant UphillA A Sheep CRC and CSIRO Livestock Industries, Chiswick, NSW B Turretfield Research Station, SARDI, Roseworthy, SA
6. Is it important to manage ewes to CS targets? John Young, Farming Systems Analysis Service, Kojonup, WA
MULESING
7. Mulesing accreditation - Vital for Wool\u27s Future, Dr Michael Paton, Department of Agriculture and Food WA,
8. Mulesing Alternatives, Jules Dorrian, Affiliation Project Manager Blowfly Control Australian Wool Inovatio
Risks of mining to salmonid-bearing watersheds
Mining provides resources for people but can pose risks to ecosystems that support cultural keystone species. Our
synthesis reviews relevant aspects of mining operations, describes the ecology of salmonid-bearing watersheds
in northwestern North America, and compiles the impacts of metal and coal extraction on salmonids and their
habitat. We conservatively estimate that this region encompasses nearly 4000 past producing mines, with
present-day operations ranging from small placer sites to massive open-pit projects that annually mine more
than 118 million metric tons of earth. Despite impact assessments that are intended to evaluate risk and inform
mitigation, mines continue to harm salmonid-bearing watersheds via pathways such as toxic contaminants, stream
channel burial, and flow regime alteration. To better maintain watershed processes that benefit salmonids, we
highlight key windows during the mining governance life cycle for science to guide policy by more accurately
accounting for stressor complexity, cumulative effects, and future environmental change.This review is based on an October 2019 workshop held at the University
of Montana Flathead Lake Biological Station (more information at https://flbs.umt.edu/
newflbs/research/working-groups/mining-and-watersheds/). We thank E. O’Neill and other
participants for valuable contributions. A. Beaudreau, M. LaCroix, P. McGrath, K. Schofield, and
L. Brown provided helpful reviews of earlier drafts. Three anonymous reviewers provided
thoughtful critiques that greatly improved the manuscript. The views expressed in this article
are those of the authors and do not necessarily represent the views or policies of the
U.S. Environmental Protection Agency. Our analysis comes from a western science perspective
and hence does not incorporate Indigenous knowledge systems. We acknowledge this gap
and highlight that the lands and waters we explore in this review have been stewarded by
Indigenous Peoples for millennia and continue to be so. Funding: The workshop was
cooperatively funded by the Wilburforce Foundation and The Salmon Science Network
funded by the Gordon and Betty Moore Foundation. Author contributions: C.J.S. led the
review process, writing, and editing. C.J.S. and E.K.S. co-organized the workshop. E.K.S. and
J.W.M. extensively contributed to all aspects of the review conceptualization, writing, and
editing. A.R.W., S.A.N., J.L.E., D.M.C., S.L.O., R.L.M., F.R.H., D.C.W., and J.W. significantly
contributed to portions of the review conceptualization, writing, and editing. J.C., M.Ca., M.Co.,
C.A.F., G.K., E.D.L., R.M., V.M., J.K.M., M.V.M., and N.S. provided writing and editing and are listed
alphabetically. Competing interests: The authors declare that they have no competing
interests. Data and materials availability: All data needed to evaluate the conclusions in the
paper are present in the paper and/or the Supplementary Materials.Ye
Evidence that Marine Temperatures Influence Growth and Maturation of Western Alaskan Chinook Salmon
<p>Chinook Salmon <i>Oncorhynchus tshawytscha</i> from western Alaska have experienced recent declines in abundance, size, and age at maturity. Declines have led to hardships for the region’s subsistence and commercial salmon harvesters, prompting calls to better understand factors affecting the life history of these populations. Western Alaskan Chinook Salmon are thought to spend their entire marine residency in the Bering Sea. The Bering Sea ecosystem demonstrates high interannual variability that is largely driven by the annual extent of sea ice. However, warming is expected to supersede interannual variability in the next several decades as a consequence of climate change. We investigated the influence of sea surface temperatures (SSTs) on the life history of western Alaskan Chinook Salmon by using information from two regional populations subject to long-term monitoring. We found strong correlations between early marine growth and SSTs. Warmer SSTs appeared to lead to a younger age at maturity, largely through the vector of augmented growth. However, we also present evidence that warmer SSTs may additionally decrease the average age of male recruits through reduced growth thresholds for early male maturation. Our results suggest that the anticipated warming of the Bering Sea will lead to higher early marine growth and a younger average age of maturation for western Alaskan Chinook Salmon.</p> <p>Received March 30, 2017; accepted July 4, 2017
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HatcheryObs
This dataframe provides observations from all five hatchery release sites over six years. The raw data has been filtered as described in the methods section of the manuscript
Network Analysis of Linkage Disequilibrium Reveals Genome Architecture in Chum Salmon
Many studies exclude loci that exhibit linkage disequilibrium (LD); however, high LD can signal reduced recombination around genomic features such as chromosome inversions or sex-determining regions. Chromosome inversions and sex-determining regions are often involved in adaptation, allowing for the inheritance of co-adapted gene complexes and for the resolution of sexually antagonistic selection through sex-specific partitioning of genetic variants. Genomic features such as these can escape detection when loci with LD are removed; in addition, failing to account for these features can introduce bias to analyses. We examined patterns of LD using network analysis to identify an overlapping chromosome inversion and sex-determining region in chum salmon. The signal of the inversion was strong enough to show up as false population substructure when the entire dataset was analyzed, while the effect of the sex-determining region on population structure was only obvious after restricting analysis to the sex chromosome. Understanding the extent and geographic distribution of inversions is now a critically important part of genetic analyses of natural populations. Our results highlight the importance of analyzing and understanding patterns of LD in genomic dataset and the perils of excluding or ignoring loci exhibiting LD. Blindly excluding loci in LD would have prevented detection of the sex-determining region and chromosome inversion while failing to understand the genomic features leading to high-LD could have resulted in false interpretations of population structure