Recruitment dynamics are subject to environmental change and ecological shifts, leading to additional uncertainties in the assessment and management of fish stocks. To be able to predict consequences of ongoing changes in ecosystems and integrate them into management strategies, it is crucial to understand the drivers of recruitment success. Recruitment is a key determinant of stock productivity and shows variability that has not been fully understood to date.
Recruitment success is determined by a range of factors that ultimately impact the overall productivity of a stock. Prior to spawning, these factors can include individual life history and resource availability, which shape the growth, condition and reproductive investment of fish.
After spawning takes place, growth and mortality rates of recruits can be influenced by intercohort dynamics, food availability, trophic interactions, habitat availability as well as environmental factors such as ocean circulation, temperature, salinity, and dissolved oxygen. Processes influencing the survival of recruits can be spatially heterogeneous, vary in scale, and be affected by climatic fluctuations or human activities, leading to spatial and temporal variability in the recruitment success.
Recruitment dynamics have been a focus topic since the beginnings of marine research, yet many key questions have remained unresolved. Identifying, disentangling and quantifying the effects of specific drivers have been particularly challenging. A thorough understanding of recruitment dynamics is, however, essential to model recruitment dynamics and to predict responses to environmental change or anthropogenic impacts. While environmental effects on recruitment and population dynamics are well established, these physical or spatial factors are rarely considered in stock assessment and management models. Interdisciplinary approaches are therefore necessary to incorporate recruitment dynamics into stock assessments and to design appropriate management strategies.
The major goal of this session is to highlight interdisciplinary approaches to understanding and modelling recruitment dynamics, with particular focus on spatial and temporal variability. We invite population dynamics papers that use empirical data to analyse or model spatial and temporal variability in recruitment. We also invite papers for the following topics:
- Reviewing the data and methods available or needed for understanding and modelling spatial and temporal recruitment variability
- Linking individual life history, stock composition and environmental impacts at all life stages to help understand variation in recruitment
- Analysing recruitment variability, synchrony between stocks and regime shifts to reveal temporal and spatial patterns
- Integrating output from physical and ecosystem models into stock assessments for the support of recruitment estimates
- Discussing best practices for including spatial and environmental information into a stock assessments and management strategy evaluations
- Exploring bioeconomic impacts of recruitment variability and management responses
