Projecting climate-driven shifts in demersal fish habitat in Iceland’s waters

Abstract

As climate change shifts marine species distribution and abundance worldwide, projecting local changes over decadal scales may be a valuable adaptive strategy for managers and industry. In Iceland, one of the top fish-producing nations in the world, long-term monitoring enables model simulations of groundfish species habitat distribution. We used generalized additive models to characterize suitable thermal habitat for 47 fish species in Iceland's waters. We then projected changes in thermal habitat by midcentury with an ensemble of five general circulation models from the Coupled Model Intercomparison Program 6 (CMIP6) and NOAA (CM2.6) and two scenarios (SSP 5-8.5 and SSP 2-4.5). We find a general northward shift in centroids of habitat distribution, with variable regional dynamics among species. Species thermal affinity was the most significant predictor of future habitat change, with warmer-water species more likely to see projected increases in suitable habitat. We present spatially explicit habitat change projections for commercially and culturally important species. These projections might serve as guideposts to inform long-term management decisions about regional and species-specific suitability for Iceland's fisheries, infrastructure investment, and risk evaluation under climate change.

Of three sharks and one chimaera: varied habitat preferences across a latitudinal range revealed by coastal and offshore surveys

“…The area off South and West Iceland is characterised by a relatively warm and saline Atlantic water, but cold‐water masses of lower salinity predominate in the north and east creating highly productive transition zone between warm Atlantic and colder Arctic water masses (Astthorsson et al ., 2007). The latitudinal difference in environmental conditions in Icelandic waters is a well‐documented limiting factor of distributions of numerous fish species in that area (Campana et al ., 2020; Mason et al ., 2021; Stefánsdóttir et al ., 2010; Valdimarsson et al ., 2012).…”

“…C. monstrosa is also abundant in the northern part along the Norwegian coast, which might be the result of a higher tolerance for colder waters and therefore an increased thermal range, as shown in et al, 2007). The latitudinal difference in environmental conditions in Icelandic waters is a well-documented limiting factor of distributions of numerous fish species in that area (Campana et al, 2020;Mason et al, 2021;Stefánsd ottir et al, 2010;Valdimarsson et al, 2012).…”