Climate change, predictive modelling and grassland specialists: assessing impacts of changing climate on the long-term conservation of Lesser Grey Shrikes (Lanius minor) in Romania

Abstract

Climate change is considered one of the greatest challenges that current biodiversity is facing. Successful adaptation of different species to climate-related changes depends on their ability to follow the habitat shift by modifying their range. We assessed the projected future range changes for a grassland specialist bird using two available climate scenarios. The model subject, the Lesser Grey Shrike (Lanius minor), is a vulnerable grassland specialist, distributed in southeastern Europe, with its European population concentrated in Romania. We created a distribution model for the species using data provided by the national Common Bird Monitoring Programme for the years 2002–2005. Several different statistical models, based on the generalised linear model and multivariate adaptive regression splines, were tested with use of the available habitat and climate data. The final working model was selected by means of the lowest root mean square error from the cross-validation process. The model was tested against two climate scenarios—A1 (integrated world, rapid economic growth) and B2 (regional development, environmentally friendly scenario)—on a long-term (2050) scale. To assess the efficiency of site-based conservation (Natura 2000 sites) as the only tool currently in place for the preservation of Lesser Grey Shrike populations in Romania, we evaluated the mean changes in suitable habitats inside the national protected area network. The projected changes show large-scale reduction of suitable habitats, both inside protected areas and at the national level, due to the forecasted shifts in grassland belts. Our results show that under both scenarios, two thirds of the seminatural grasslands will be out of the recent protected area system by 2050. Small protected areas will lose more habitats than larger ones, irrespective of the Lesser Grey Shrike populations breeding therein. These results suggest that current site-based protection measures will become largely insufficient for the conservation of seminatural grasslands and the associated flora and fauna in the long term in Romania.