A1 Journal article (refereed)
Temporary Allee effects among non‐stationary recruitment dynamics in depleted gadid and flatfish populations (2022)
Tirronen, M., Perälä, T., & Kuparinen, A. (2022). Temporary Allee effects among non‐stationary recruitment dynamics in depleted gadid and flatfish populations. Fish and Fisheries, 23(2), 392-406. https://doi.org/10.1111/faf.12623
JYU authors or editors
Publication details
All authors or editors: Tirronen, Maria; Perälä, Tommi; Kuparinen, Anna
Journal or series: Fish and Fisheries
ISSN: 1467-2960
eISSN: 1467-2979
Publication year: 2022
Publication date: 22/10/2021
Volume: 23
Issue number: 2
Pages range: 392-406
Publisher: Wiley
Publication country: United Kingdom
Publication language: English
DOI: https://doi.org/10.1111/faf.12623
Publication open access: Openly available
Publication channel open access: Partially open access channel
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/78835
Abstract
Many considerably declined fish populations have not fully recovered despite reductions in fishing pressure. One of the possible causes of impaired recovery is the (demographic) Allee effect. To investigate whether low-abundance recruitment dynamics can switch between compensation and depensation, the latter implying the presence of the Allee effect, we analysed the stock–recruitment time series of 17 depleted cod-type and flatfish populations using a Bayesian change point model. The recruitment dynamics were represented with the sigmoidal Beverton–Holt and the Saila–Lorda stock–recruitment models, allowing the parameters of the models to shift at a priori unknown change points. Our synthesis study questions the common assumption that recruitment is stationary and compensatory and the high amount of scatteredness often present in stock–recruitment data is only due to random variation. When a moderate amount of such variation was assumed, stock–recruitment dynamics were best explained by a non-stationary model for 53% of the populations, which suggests that these populations exhibit temporal changes in the stock–recruitment relationship. For four populations, we found shifts between compensation and depensation, suggesting the presence of temporary Allee effects. However, the evidence of Allee effects was highly dependent on the priors of the stock–recruitment model parameters and the amount of random variation assumed. Nonetheless, detection of changes in low-abundance recruitment is essential in stock assessment since such changes affect the renewal ability of the population and, ultimately, its sustainable harvest limits.
Keywords: fish populations; recovery (return); population dynamics; fishery; overfishing; Gadiformes; flatfishes
Free keywords: change point model; compensation; depensation; regime shifts; stock–recruitment
Contributing organizations
Related projects
- Complex eco-evolutionary dynamics of aquatic ecosystems
faced with human-induced and environmental stress- Kuparinen, Anna
- Research Council of Finland
- Resolving complex eco-evolutionary dynamics of aquatic ecosystems faced with human-induced and environmental alterations
- Kuparinen, Anna
- European Commission
Ministry reporting: Yes
Reporting Year: 2022
JUFO rating: 3