Threatened skates exhibit abiotic niche stability despite climate change in the southwestern Atlantic Ocean

Abstract

Climatic changes are disrupting distribution patterns of populations through shifts in species abiotic niches and habitat loss. The abiotic niche of marine benthic taxa such as skates, however, may be more climatically stable compared with the upper layers of the water column, which are more exposed to immediate impacts of warming. Here, we estimate climate change impacts in Riorajini, a tribe of four skates, as a proxy to evaluate the vulnerability of a temperate coastal zone in the Southwest Atlantic, and study niche dynamics in a scenario of environmental changes on this group of threatened species. We modelled the abiotic niche of each species under present climatic conditions (2000–2014), projected them to the future (2100), then measured distributional stability, expansion, and unfilling. Our results revealed abiotic stability between the scenarios modelled despite the advancement of climate change, suggesting that the benthic layers where these skates occur may be a refuge from the increasing thermal stress. However, the exposure of shallow waters to climate change may be detrimental to nursery habitats. Thus, although their abiotic niche may remain stable in the future, the loss of extension of occurrence might be a peril for them with climate change.