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 edgeover 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.

Groundfish biodiversity change in northeastern Pacific waters under projected warming and deoxygenation

“…This result is consistent with estimates that suggest that the range edges of marine species are generally, but not universally, changing with warming ocean water temperatures (Sunday et al 2012;Fredston et al 2021). In Canadian Pacific waters, there is evidence that changes in temperature and oxygen are impacting the distribution and densities of groundfish species (English et al 2021), but that these changes have not yet resulted in major changes in the diversity and composition of the groundfish community (Thompson et al 2022).…”

“…Range shifts for species in west coast North American waters are projected to be particularly large, with many species' range limits expected to change by more than 1000 km by the end of the century under high greenhouse gas emissions scenarios (Morley et al 2018). This result is consistent with estimates that suggest that the range edges of marine species are generally, but not universally, changing with warming ocean water temperatures (Sunday et al 2012;Fredston et al 2021). In addition, there is evidence that some, but not all, marine species are shifting to deeper depths as conditions warm (Chaikin et al 2022).…”