Range edges of North American marine species are tracking temperature
over decades
Abstract
Understanding range edges is key to addressing fundamental biogeographic
questions about abiotic and biotic drivers of species distributions.
Range edges are where colonization and extirpation happen, so their
dynamics are also important for natural resource management and
conservation. We quantified positions for 153 range edges of marine
fishes and invertebrates from three US continental shelf regions using
decades of survey data and a spatiotemporal model to account for changes
in survey design. We analyzed whether range edges maintained their edge
thermal niches—temperature extremes at the range edge—over time.
Most range edges (86%) maintained either cold or warm temperature
extremes; 73% maintained both. However, the substantial fraction of
range edges that altered their thermal niche underscore the multiplicity
of relevant drivers. This study suggests that temperate marine species
largely maintained their edge thermal niches during rapid change and
provides a blueprint for testing temperature tracking of species range
edges.