Ecology and Trophic Dynamics of Forage Fish Species

Forage fishes such as sandeels, anchovies and herrings are pivotal intermediaries in marine food webs, channeling energy from plankton to higher predators. Their biomass dynamics govern nutrient flux, support commercially important fisheries and sustain populations of seabirds, marine mammals and larger piscivores.

These species exhibit complex life histories influenced by seasonal phenology, temperature variability and hydrographic conditions. Changes in prey availability, ocean warming and fishing pressure can reshape their growth, recruitment and spatial distributions, with cascading impacts on ecosystem stability and resilience. Insight into these processes underpins ecosystem-based management and conservation of marine biodiversity.

Research from Nature Portfolio

Recent studies have shown that temperature-dependent phenological shifts in key forage fish such as sandeels can alter the synchrony between larval hatching and copepod prey peaks, leading to trophic mismatch. By analysing multi-year time-series of sea temperature, fish larval abundance and zooplankton production in a Scottish coastal system, researchers have quantified how differential thermal cues drive gonad development in fishes and egg production in copepods. Projected warming scenarios indicate a rising probability of asynchronous predator–prey phenology, with marked declines in recruitment success under future climate regimes. This work emphasises the need to integrate temperature-sensitive life stages into predictive models of forage fish population dynamics.

Ecology and Trophic Dynamics of Forage Fish Species publication trend

The graph below shows the total number of articles in ecology and trophic dynamics of forage fish species across all publications each year (not limited to Nature Index journals).

Technical terms

Forage fish: Small schooling fish that occupy intermediate trophic levels and transfer energy from plankton to larger predators.

Trophic mismatch: A temporal decoupling between the peak availability of prey and the life-cycle events of predators, often driven by environmental change.

Phenology: The study of the timing of seasonal biological events in relation to environmental factors.

Metabarcoding: A genetic technique that uses environmental DNA to identify multiple species simultaneously from water or sediment samples.

Recruitment: The addition of new individuals to a population through growth and survival of juveniles to a size or stage relevant to the ecosystem or fishery.

References

1. Understanding temperature effects on recruitment in the context of trophic mismatch. Scientific Reports (2019).
2. Environmental DNA reveals fine‐scale spatial and temporal variation of marine mammals and their prey species in a Scottish marine protected area. Environmental DNA (2024).
3. The role of sand lances (Ammodytes sp.) in the Northwest Atlantic Ecosystem: A synthesis of current knowledge with implications for conservation and management. Fish and Fisheries (2020).
4. Sensitivity of sand lance to shifting prey and hydrography indicates forthcoming change to the northeast US shelf forage fish complex. ICES Journal of Marine Science (2021).