Climatic changes are disrupting otherwise tight trophic interactions between predator and prey. Most of the earlier studies have primarily focused on the temporal dimension of the relationship in the framework of the match-mismatch hypothesis. This hypothesis predicts that predator's recruitment will be high if the peak of the prey availability temporally matches the most energy-demanding period of the predators breeding phenology. However, the match-mismatch hypothesis ignores the level of food abundance while this can compensate small mismatches. Using a novel time-series model explicitly quantifying both the timing and the abundance component for trophic relationships, we here show that timing and abundance of food affect recruitment differently in a marine (cod/zooplankton), a marine-terrestrial (puffin/herring) and a terrestrial (sheep/vegetation) ecosystem. The quantification of the combined effect of abundance and timing of prey on predator dynamics enables us to come closer to the mechanisms by which environment variability may affect ecological systems.

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Global warming is a nonlinear process, and temperature may increase in a stepwise manner. Periods of abrupt warming can trigger persistent changes in the state of ecosystems, also called regime shifts. The responses of organisms to abrupt warming and associated regime shifts can be unlike responses to periods of slow or moderate change. Understanding of nonlinearity in the biological responses to climate warming is needed to assess the consequences of ongoing climate change. Here, we demonstrate that the population dynamics of a long-lived, wide-ranging marine predator are associated with changes in the rate of ocean warming. Data from 556 colonies of black-legged kittiwakes Rissa tridactyla distributed throughout its breeding range revealed that an abrupt warming of sea-surface temperature in the 1990s coincided with steep kittiwake population decline. Periods of moderate warming in sea temperatures did not seem to affect kittiwake dynamics. The rapid warming observed in the 1990s may have driven large-scale, circumpolar marine ecosystem shifts that strongly affected kittiwakes through bottom-up effects. Our study sheds light on the nonlinear response of a circumpolar seabird to large-scale changes in oceanographic conditions and indicates that marine top predators may be more sensitive to the rate of ocean warming rather than to warming itself.