Session descriptions

1. Environmental impacts on subarctic and arctic ecosystems: species-specific responses

Organisms in subarctic and arctic marine ecosystems are subjected to extreme seasonal and interannual variability in temperature and ice conditions. This variability is superimposed on strong decadal patterns and a pronounced anthropogenic warming trend, which has already resulted in loss of multiyear sea ice, earlier ice melt, a longer ice-free season, changes in advection, and changes in primary and secondary production. This session explores bottom-up impacts of both interannual variability and long-term environmental trends on the growth, spawning and reproduction, natural mortality, distribution and migration, and abundance and recruitment of individual fish and invertebrate species, with an emphasis on developing mechanistically based predictions that can be used in projecting impacts of climate change on these populations. These may include direct impacts on fish and invertebrates, as well as indirect impacts through changes in primary and secondary production. We also encourage submissions that examine phenotypic plasticity in biological responses and the ability of species to adapt to changing conditions.

2. Environmental impacts on subarctic and arctic ecosystems: community structure, biodiversity, energy flow, and trophodynamics

High-latitude marine food webs display a strong latitudinal gradient in the abundance and diversity of fish communities. Subarctic ecosystems include some of the largest and most important commercial fisheries in the world, supported in part by large crustacean and gadid populations that rely on high benthic productivity and lipid-rich zooplankton or small forage fish to transfer energy from lower to upper trophic levels. These systems have undergone large, environmentally driven changes in the past, including pronounced regime shifts. Arctic food webs are relatively species-poor, especially in the pelagic environment, with much of the energy from short, intense spring blooms transferred to seasonal migrants, including large migratory fish, seabirds, and mammals. This session explores the impacts of environmental variability and climate change on the structure and functioning of these systems, including variability in predator-prey dynamics, pelagic-benthic coupling, food-web structure, the role of portfolio effects, and the potential “borealization” of the Arctic.

3. Physiological effects of ocean acidification, oxygen limitation, and temperature stress on high-latitude fish and shellfish

Subarctic and arctic marine ecosystems are expected to experience both the largest changes in ocean pH and the largest temperature changes, with unknown consequences for fish and shellfish populations. Early life stages (eggs, larvae) are expected to be most vulnerable, but the effects are likely to vary among ecosystems and species and may be confounded with fishing effects. We invite presentations that examine direct or indirect effects of acidification, oxygen limitation, and temperature stress on fish and shellfish. We specifically encourage submissions that focus on the combined effects of these stressors, on the ability of individuals to acclimatize to changing conditions, and on the capacity of populations to adapt (including transgenerational effects).

4. Incorporating environmental effects and accounting for changing life history traits in the assessment and management of fish populations

Short- and long-term environmental variability affects the distribution, feeding, growth, recruitment, maturation, and other characteristics of high-latitude fish and invertebrate populations. Such effects are often non-stationary and are challenging to accurately quantify and incorporate into single-species or multispecies population dynamics models. Moreover, traits and vital rates may change over time. We seek examples that incorporate environmental effects and account for changing traits in the assessment and management process to improve estimates of reference points, enhance our ability to predict future abundances in a changing environment, or support the development of environmentally dependent harvest control rules. We seek contributions that explore how a better understanding of environmentally driven dynamics can be used to develop and improve predictions and projections of assessed populations on both the short- and long-term timescale. To help bridge the gap from large-scale climate projections to applied fisheries problems, we also encourage papers that address the use of IPCC model projections in fisheries management applications.

5. Evaluating management strategies under projected environmental changes

Environmental changes pose significant challenges for fisheries managers who seek to develop strategies that sustain valuable high-latitude fisheries in the long term. Management targets for fishing mortality and biomass reference points are often calculated by assuming stationary population processes, an assumption that is likely violated under climate change. Climate change is also expected to alter the spatial distribution, size and maturity schedule, and abundance of target and nontarget species, which will challenge existing management strategies that have implemented system level overall caps on removals, catch share, and marine spatial planning agreements. The climate change signal will be imbedded within natural variability (interannual or decadal) creating a dilemma for managers regarding when, or if, climate-ready management amendments should be considered. In this session we explore data needs, tools, and approaches that support the development of climate-enhanced management strategy evaluations.

6. Coping with environmental variability and climate change: perspectives from coastal communities

Fishery-dependent communities in the Subarctic and Arctic have persisted for millennia in the face of environmental variability, but substantial disruptions to communities have occurred due to both overfishing and environmentally driven changes in fish populations. Anticipated changes in the abundance and distribution of fishes will affect coastal communities whose livelihood depends on fish for subsistence, recreational fishing, or commercial harvests. This session examines the resilience and adaptive capacity of fishery-dependent communities in the face of environmental changes. We invite contributions that address management challenges for communities associated with environmental variability and adaptation options in the face of environmental changes.