Evidence for adaptive strategies in larval capelin on the northeastern coast of Newfoundland, Canada.

This article investigates adaptive reproductive strategies in capelin (Mallotus villosus), a forage fish species in coastal Newfoundland, focusing on whether larvae time hatching to match favorable environmental conditions ("match/mismatch") or use bet-hedging by extending spawning to disperse risk. From 2018 to 2021, larval densities were positively associated with zooplankton prey biomass but showed no relationship with predator biomass or temperature, providing limited support for the match/mismatch hypothesis and no support for the Coastal Water Mass Replacement (CWMR) hypothesis. High variability in larval emergence timing and traits supports a bet-hedging strategy, while larval condition varied more between years than between intertidal and subtidal spawning habitats, suggesting that annual environmental factors have a greater influence on larval condition and potential recruitment than spawning habitat shifts. The findings imply that climate-driven shifts toward subtidal spawning may have limited immediate impact on stock recovery, but years with poor larval condition, such as 2018, may contribute to the continued collapse of the Newfoundland capelin stock.