Get up early: Revealing behavioral responses of sandeel to ocean warming using commercial catch data. Issue 23 (26th November 2021)

• Record Type: Journal Article
• Authors: Henriksen, Ole; Rindorf, Anna; Mosegaard, Henrik; Payne, Mark R.; van Deurs, Mikael
• Is Part Of: Ecology and evolution. Volume 11:Issue 23(2021)
• Page Start: 16786
• Page End: 16805
• Publication Date: 2021-11-26
• Subjects: climate change -- dormancy -- emergence -- fish -- North Sea -- phenology -- temperature; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.8310
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: Warming of the oceans and shifts in the timing of annual key events are likely to cause behavioral changes in species showing a high degree of site fidelity. While this is well studied in terrestrial systems, there are fewer examples from the marine environment. Sandeel ( Ammodytes marinus ) is a small eel‐shaped teleost fish with strong behavioral attachment to sandy habitats in which they are buried from late summer through winter. When spring arrives, the sandeel emerge to feed during the day for several of months before returning to the sand for overwintering refuge. Using fisheries data from the North Sea, we investigated whether catch rates reflect the timing of emergence and if seasonal patterns are related to temperature and primary production. Catch per unit effort (CPUE) was used to describe sandeel emergence. We developed indicators of the relative timing of the emergence from the winter sand refuge and the subsequent growth period. Different modeling approaches were used to investigate the relationship with bottom temperature and primary production. Variation in emergence behavior was correlated with variation in sea bottom temperature. Warmer years were characterized by earlier emergence. Significant warming over the last three decades was evident in all sandeel habitats in the North Sea throughout most of their adult life history, though no net shift in the phenology of emergence was detected. Minimum temperature during spring was a better predictor of emergence behavior than, for example, degree days. This study emphasizes how temperature‐induced changes in behavior may have implications for predators and fisheries of sandeel. The method can be applied to other species for which the timing of exploitation (i.e., fisheries) and species life history are well matched. Abstract : The fishery for sandeels in the North Sea comprise several species from the Ammodytidae family. Although, the majority of catches comprises the lesser sandeel ( Ammodytes marinus, smaller individual), other species such as the great sandeel ( Hyperoplus lanceolatus, larger individual) also occur in the fishery. Thus, the findings from this study might also be valid and relevant for the other species (also worth mentioning, A. tobianus, H. immaculatus and Gymnammodytes semisquamatus ) that co‐occur with the lesser sandeel in some areas of the North Sea.