Potential adaptability of marine turtles to climate change may be hindered by coastal development in the USA

Abstract

Marine turtles may respond to projected climatic changes by shifting their nesting range to climatically suitable areas, which may result in either increased exposure to threats or fewer threats. Therefore, there is the need to identify whether habitat predicted to be climatically suitable for marine turtle nesting in the future will be affected by future threats and hinder marine turtles’ ability to adapt. We modelled the geographic distribution of climatically suitable nesting habitat for marine turtles in the USA under future climate scenarios, identified potential range shifts by 2050, determined impacts from sea-level rise, and explored changes in exposure to coastal development as a result of range shifts. Overall nesting ranges of marine turtle species were not predicted to change between the current and future time periods, except for the northern nesting boundaries for loggerhead turtles. However, declines in climatically suitable nesting grounds were predicted; loggerhead turtles will experience the highest decreases (10%) in climatically suitable habitat followed by green (7%) and leatherback (1%) turtles. However, sea-level rise is projected to inundate 78–81% of current habitat predicted to be climatically suitable in the future, depending on species and scenario. Nevertheless, new beaches will also form, and suitable nesting habitat could be gained, with leatherback turtles potentially experiencing the biggest percentage gain in suitable habitat.