Marine fish traits follow fast-slow continuum across oceans

A fundamental challenge in ecology is to understand why species are found
where they are and predict where they are likely to occur in the future.
Trait-based approaches may provide such understanding, because it is the
traits and adaptations of species that determine which environments they
can inhabit. It is therefore important to identify key traits that
determine species distributions and investigate how these traits relate to
the environment. Based on scientific bottom-trawl surveys of marine fish
abundances and traits of >1,200 species, we investigate
trait-environment relationships and project the trait composition of
marine fish communities across the continental shelf seas of the Northern
hemisphere. We show that traits related to growth, maturation and lifespan
respond most strongly to the environment. This is reflected by a
pronounced “fast-slow continuum” of fish life-histories, revealing that
traits vary with temperature at large spatial scales, but also with depth
and seasonality at more local scales. Our findings provide insight into
the structure of marine fish communities and suggest that global warming
will favour an expansion of fast-living species. Knowledge of the global
and local drivers of trait distributions can thus be used to predict
future responses of fish communities to environmental change.