Developing Strategies for Improved Assessment and Ecosystem-Based Management of Canadian Northern Dolly Varden

2012 ◽  
pp. 169-188 ◽  
Author(s):  
K. Howland ◽  
N. Mochnacz ◽  
C. Gallagher ◽  
R. Tallman ◽  
H. Ghamry ◽  
...  
Keyword(s):  
Dolly Varden ◽  
Ecosystem Based Management ◽  
Northern Dolly Varden ◽  
Developing Strategies

Northern Dolly Varden charr total mercury concentrations: variation by life-history type

Hydrobiologia ◽  
2016 ◽  
Vol 783 (1) ◽  
pp. 159-175 ◽  
Author(s):  
L. Tran ◽  
J. D. Reist ◽  
M. Power
Keyword(s):  
Life History ◽  
Total Mercury ◽  
Dolly Varden ◽  
Northern Dolly Varden

Life-history characteristics and landscape attributes as drivers of genetic variation, gene flow, and fine-scale population structure in northern Dolly Varden (Salvelinus malma malma) in Canada

2015 ◽  
Vol 72 (10) ◽  
pp. 1477-1493 ◽  
Author(s):  
Les N. Harris ◽  
Robert Bajno ◽  
Colin P. Gallagher ◽  
Itsuro Koizumi ◽  
Lucy K. Johnson ◽  
...  
Keyword(s):  
Population Structure ◽  
Genetic Variation ◽  
Life History ◽  
Gene Flow ◽  
Isolation By Distance ◽  
Dolly Varden ◽  
Salvelinus Malma ◽  
Dolly Varden Salvelinus Malma ◽  
Northern Dolly Varden ◽  
Population Demographic

The northern Dolly Varden (Salvelinus malma malma) displays variable life-history types and occupies freshwater habitats with varying levels of connectivity. Here, we assayed microsatellite DNA variation in northern Dolly Varden from the western Canadian Arctic to resolve landscape and life-history variables driving variation in genetic diversity and population structure. Overall, genetic variation was highest in anadromous populations and lowest in those isolated above waterfalls, with stream-resident forms intermediate between the two. Anadromous and isolated populations were genetically divergent from each other, while no genetic differentiation was detectable between sympatric anadromous and stream-resident forms. Population structure was stable over 25 years, hierarchically organized, and conformed to an isolation-by-distance pattern, but stream-isolated forms often deviated from these patterns. Gene flow occurred primarily among Yukon North Slope populations and between sympatric anadromous and resident forms. These results were sex-dependent to some extent, but were influenced more by reproductive status and life history. Our study provides novel insights into the life history, population demographic, and habitat variables that shape the distribution of genetic variation and population structure in Arctic fluvial habitats while providing a spatial context for management and conservation.

Summer growth patterns of northern Dolly Varden (Salvelinus malma) smolts from the Prudhoe Bay region of Alaska

1997 ◽  
Vol 54 (5) ◽  
pp. 1103-1110 ◽  
Author(s):  
R G Fechhelm ◽  
J D Bryan ◽  
W B Griffiths ◽  
L R Martin
Keyword(s):  
Prey Availability ◽  
Late Summer ◽  
Early Summer ◽  
Growth Patterns ◽  
Dolly Varden ◽  
Salvelinus Malma ◽  
Dolly Varden Salvelinus Malma ◽  
Northern Dolly Varden ◽  
Stock Mixing ◽  
Rates Of Growth

Summer length growth patterns of northern Dolly Varden (Salvelinus malma) smolts from the Sagavanirktok River, northern Alaska, were analyzed for the years 1985-1994 and found to be sigmoidal, indicating slow rates of growth in early and late summer with the most rapid growth occurring in midseason. Nonlinear logistic regression functions of mean cohort length against date provided a reasonable fit of the data for all years except for 1991, accounting for more than 94% (r2 values ranged from 0.95 to 0.99) of the variation in mean daily length in any given year. Slow growth in early summer is in direct contrast with the growth patterns reported for juvenile broad whitefish (Coregonus nasus) and Arctic cisco (C. autumnalis) which inhabit the Sagavanirktok River and estuary. Some possible explanations for the observed Dolly Varden growth patterns include migration, dispersal, prey availability, water quality, and stock mixing.

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