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Juneau, AK, United States

The Alaska Department of Fish and Game is a department within the government of Alaska. The Department of Fish and Game manages Alaska's fish, game, and aquatic plant resources. Wikipedia.

Grant W.S.,Alaska Department of Fish and Game | Liu M.,Ocean University of China | Gao T.,Ocean University of China | Yanagimoto T.,Japan National Research Institute of Fisheries Science
Molecular Phylogenetics and Evolution | Year: 2012

A previous analysis of Pacific herring mitochondrial (mt) DNA with Bayesian skyline plots (BSPs) was interpreted to reflect population growth in the late Pleistocene that was preceded by population stability over several hundred thousand years. Here we use an independent set of mtDNA control region (CR) sequences and simulations to test these hypotheses. The CR haplotype genealogy shows three deeply divided lineages, A, B and C, with divergences ranging from d=1.6% to 1.9% and with similar genetic diversities (h=0.95, 0.96, 0.94; Θπ=0.011, 0.012, 0.014, respectively). Lineage A occurs almost exclusively in the NW Pacific and Bering Sea, but lineages B and C are co-distributed in the Northeastern Pacific. This distribution points to a historical allopatric separation between A and B-C across the North Pacific during Pleistocene glaciations. The origins of B and C are uncertain. One hypothesis invokes long-term isolation of lineage C in the Sea of Cortez, but the present-day lack of geographical segregation from lineage B argues for lineage sorting to explain the deep divergence between B and C. BSPs depict rapid population growth in each lineage, but the timing of this growth is uncertain, because of questions about an appropriate molecular clock calibration. We simulated historical demographies under a Pleistocene climate model using observed genetic parameters. BSPs for these sequences showed rapid population growth after the Last Glacial Maximum (LGM) 18-20. k. years ago and a flat population history during previous climate fluctuations. Population declines during the LGM appear to have erased signals of previous population fluctuations. © 2012 Elsevier Inc. Source

Hundertmark K.J.,University of Alaska Fairbanks | van Daele L.J.,Alaska Department of Fish and Game
Conservation Genetics | Year: 2010

The population of elk (Cervus elaphus roosevelti) inhabiting Afognak Island, Alaska, USA arose from an introduction of 8 individuals from an established population in Washington, USA in 1929, and recently peaked at approximately 1,400 individuals. We examined indices of diversity for 15 microsatellite loci in the Afognak population and compared them to levels in the parent population to determine effects of translocation and demography on genetic variation. The Afognak population differed significantly (P < 0.0001) from the source population in both allele and genotype frequencies. Allelic richness, number of private alleles and multilocus heterozygosity, but not percent loci polymorphic, were significantly lower in Afognak elk. Mean inbreeding coefficients within Afognak (f = 0.019) and source (f = -0.006) populations did not differ significantly from zero. Despite the demographic bottleneck, no evidence of a genetic bottleneck in the Afognak population was detected using a test for heterozygosity excess or mode shift of allele frequencies. Simulations indicated that rapid population growth after the translocation resulted in heterozygosity excess for only 8 years. Conversely, a statistic testing for a bottleneck signature in the ratio of allele number to allele size range (M-ratio) was significant for both the Afognak and source populations, suggesting that the Afognak population had effectively undergone serial bottlenecks. Nonetheless, Afognak failed to show a smaller M-ratio than the parent population, suggesting a failure of that statistic to detect the bottleneck associated with introduction. We show that a severe bottleneck followed by rapid population growth may be undetectable using available tests. © Springer Science+Business Media B.V. 2009. Source

Identification of variables that can be used to predict discard mortality is an important step towards improving estimates of total fishery removals. I explored the utility of capture depth, six external signs of barotrauma, two behavioral responses, and an impairment index that summed the physical and behavioral impairment associated with rapid decompression at predicting the submergence success of hook-and-line captured yelloweye (n= 95) and quillback (n= 65) rockfish that were released at the water's surface. Random forests classification models were used to identify the relative importance of predictor variables (n= 11) for each species and to explore the ability of these variables to accurately predict individual submergence success. Capture depth was identified as the most important variable in predicting yelloweye rockfish submergence but provided little improvement to the quillback rockfish model. The impairment index and the barotrauma sign associated with maximal gas retention were identified as important predictor variables for both yelloweye and quillback rockfish. These findings suggest that the impairment index, unlike capture depth, was able to account for individual variability in submergence success or failure of quillback rockfish. © 2012. Source

Grant W.S.,Alaska Department of Fish and Game
Journal of Heredity | Year: 2015

Sequence mismatch analysis (MMA) and Bayesian skyline plots (BSP) are commonly used to reconstruct historical demography. A survey of 173 research articles (2009-2014), which included estimates of historical population sizes from mtDNA or cpDNA, shows a widespread genetic signature of demographic or spatial population expansion in species of all major taxonomic groups. Associating these expansions with climatic events can provide insights into the origins of lineage diversity, range expansions (or contractions), and speciation. However, several variables can introduce error into reconstructions of demographic history, including levels of sequence polymorphism, sampling scheme, sample size, natural selection, and estimates of mutation rate. Most researchers use substitution rates estimated from divergences in phylogenetic trees dated with fossils, or geological events. Recent studies show that molecular clocks calibrated with phylogenetic divergences can overestimate the timings of population-level events by an order of magnitude. Overestimates disconnect historical population reconstructions from climatic history and confound our understanding of the factors influencing genetic variability. If mismatch distributions and BSPs largely reflect demographic history, the widespread signature of population expansion in vertebrate, invertebrate, and plant populations appears to reflect responses to postglacial climate warming. © The American Genetic Association 2015. All rights reserved. Source

Gillanders B.M.,University of Adelaide | Munro A.R.,University of Adelaide | Munro A.R.,Alaska Department of Fish and Game
Limnology and Oceanography | Year: 2012

We investigated the effect of hypersaline conditions on the water chemistry of the Coorong Lagoon, the terminal estuary of Australia's largest river, and the otolith chemistry of a common fish within the system. Water samples and fish were collected from 10 sites along the Coorong, ranging in salinity from 5.8 to 123.4, on six occasions over 14 months. Water (Ca, Ba, Mg, Mn, and Sr) and otolith (Ba: Ca, Sr: Ca, Mg: Ca, Mn: Ca, Na: Ca, Li: Ca, δ13C, and δ18O) concentrations were measured. Water Sr, Mg, and Ca concentrations exhibited conservative behavior (i.e., concentrations increased with salinity). Water Ba concentration decreased from near-freshwater to marine salinities followed by an increase from marine to hypersaline waters, a pattern not previously reported in the literature. Three of the six otolith element: Ca ratios andδ18O showed significant linear correlations with salinity, but the best fit model for Ba: Ca was a segmented regression with a breakpoint. Positive linear correlations were also found between otolith Ba: Ca and water Ba: Ca, as well as otolith Mg: Ca and water Mg: Ca. Results have implications for reconstructing past salinities inhabited by fish, because they imply that several elemental and isotopic ratios will be necessary to determine whether fish have inhabited, or been exposed to, hypersaline environments. © 2012, by the Association for the Sciences of Limnology and Oceanography, Inc. Source

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