0000000001313153

AUTHOR

Lauren A. Rogers

Fine-scale population dynamics in a marine fish species inferred from dynamic state-space models

1. Identifying the spatial scale of population structuring is critical for the conservation of natural populations and for drawing accurate ecological inferences. However, population studies often use spatially aggregated data to draw inferences about population trends and drivers, potentially masking ecologically relevant population sub‐structure and dynamics. 2. The goals of this study were to investigate how population dynamics models with and without spatial structure affect inferences on population trends and the identification of intrinsic drivers of population dynamics (e.g. density dependence). 3. Specifically, we developed dynamic, age‐structured, state‐space models to test differe…

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Habitat effects on population connectivity in a coastal seascape

Published version of an article from: Marine Ecology Progress Series. Also available from Inter Research: http://dx.doi.org/10.3354/meps10944 Knowing how population connectivity varies across heterogeneous habitats can provide insight into the mechanisms underlying population structuring, and ultimately help to inform conservation and management actions. We studied whether the spatial extent of connectivity in coastal Atlantic cod Gadus morhua varied with coastal topography, hypothesizing that connectivity during all life stages would be greater among open, exposed habitats compared to sheltered, fjord-like habitats. We tested this hypothesis using (1) an extensive mark-recapture data set t…

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Recruitment signals in juvenile cod surveys depend on thermal growth conditions

Coastal seine surveys contain some of the only direct measures of age-0 abundance for Atlantic cod (Gadus morhua) and Pacific cod (Gadus macrocephalus), yet their utility in forecasting future year-class strength has not been evaluated among regions. We analyzed coastal time series from the Gulf of Alaska, Newfoundland, and Norway to test the hypothesis that recruitment signals are stronger when assessed under thermal conditions that provide high juvenile growth potential. Weaker recruitment signals were associated with low growth potential from cold winters (Newfoundland) and recent warmer summers (Norway). We conclude that temperature-dependent growth strongly influences the utility of c…

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Inferring genetic connectivity in real populations, exemplified by coastal and oceanic atlantic cod

Significance Estimates of migration are important for understanding the dynamics of natural populations. A statistic known as FST is often used to measure levels of genetic differentiation among natural populations. Equations that translate FST into estimates of migration are based on “ideal” populations, which are subject to many simplifying assumptions compared with real populations. Therefore, theoretical estimates of migration might not be realistic. We modeled populations of Atlantic cod in the North Sea and the adjacent Skagerrak region to compare how migration is related to the complexities of real populations, and how actual migration compares with predictions based on theory. Resul…

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Data from: Fine-scale population dynamics in a marine fish species inferred from dynamic state-space models

Identifying the spatial scale of population structuring is critical for the conservation of natural populations and for drawing accurate ecological inferences. However, population studies often use spatially aggregated data to draw inferences about population trends and drivers, potentially masking ecologically relevant population sub-structure and dynamics. The goals of this study were to investigate how population dynamics models with and without spatial structure affect inferences on population trends and the identification of intrinsic drivers of population dynamics (e.g. density dependence). Specifically, we developed dynamic, age-structured, state-space models to test different hypoth…

research product