How will climate change affect endangered Mediterranean waterbirds?

Abstract

Global warming and direct anthropogenic impacts, such as water extraction, largely affect water budgets in Mediterranean wetlands, thereby increasing wetland salinities and isolation, and decreasing water depths and hydroperiods (duration of the inundation period). These wetland features are key elements structuring waterbird communities. However, the ultimate and net consequences of these dynamic conditions on waterbird assemblages are largely unknown. We combined regular sampling of waterbird presence through one annual cycle with in-situ data on relevant environmental predictors of waterbird distribution to model habitat selection for 69 species in a typical Mediterranean wetland network in southwestern Spain. Species associations with environmental features were subsequently used to predict changes in habitat suitability for each species under three climate change scenarios (encompassing changes in environmental predictors that ranged from 10% to 50% change as predicted by regional climatic models). Waterbirds distributed themselves unevenly throughout environmental gradients and water salinity was the most important gradient structuring the distribution of the community. Environmental suitability for the guilds of diving birds and vegetation gleaners will decline in future climate scenarios, while many small wading birds will benefit from changing conditions. Resident species and those that breed in this wetland network will also be more negatively impacted than those using this area for wintering or stopover. We provide a tool that can be used in a horizon-scanning framework to identify emerging issues in waterbird conservation and to anticipate suitable management actions.

Fast and Automatic Data-Driven Thresholding for Inundation Mapping with Sentinel-2 Data

“…Hydroperiod is a critical parameter that shapes the distribution of aquatic plants and animals and determines the habitat available for many of the living organisms, including migratory and endemic water birds, in the marshland [2,49].…”

Status and Trends of the Ferruginous Duck’s (Aythya nyroca) Wintering Population in Morocco: Analysis of 35 Years of Winter Census Data (1983-2017)

“…Other factors contributing to the decline in the global species populations are related to the introduction of nonnative species and predators [17]. The increased drought due to climate change can also pose a threat [16,17,34], as its breeding depends on sufficient water levels, which can play a role in maintaining feeding areas for ducks and potentially decreasing the predation rate of nests [8,14,29,35]. Moreover, hunting represents a serious threat to the species, especially during the autumn passage and on its wintering areas in East Africa (e.g., Sudan) [11,36].…”

A More Effective Ramsar Convention for the Conservation of Mediterranean Wetlands

“…Climate change is expected to lead to prolong droughts and increase temperatures (Mariotti et al, 2015;Cramer et al, 2018) which will reduce freshwater availability and quality. This is expected to particularly affect the biodiversity of Mediterranean wetlands and their related ecosystem services (Ramírez et al, 2018). Additional impacts of climate change on Mediterranean wetlands include direct impacts (e.g., sea level rises, decreased precipitation) and indirect impacts (e.g., increasing demands for water).…”