The U. S. National Wildlife Refuge System (NWRS) represents a large network of high priority conservation areas. Like all other protected areas around the globe, the refuges are likely to experience shifts in habitat composition and configuration as a result of climate change. Maintaining connectivity is seen as a key method for mitigating these changes.
A new study by Hamilton et al. looks at one specific factor that may impact the ability of the NWRS to maintain connectivity in the future: the growth of housing developments near refuges. The study focused on 455 refuges and evaluated the past, current, and predicted future effects (1940-2030) of housing growth on conservation “opportunity areas”, i.e. open spaces with very low housing density where managers could focus conservation efforts. It also identified current habitat corridors near the refuges, and looked at whether there was regional variation in the potential for connecting the refuges.
Unsurprisingly, the study showed that number and size of opportunity areas decreased with time, and even more strongly with distance from a refuge. The Northeast contained the greatest number of refuges that had zero opportunity areas and few corridors. There are also few opportunities to restore connectivity around refuges east of the Appalachian Mountains overall, mostly from the lack of undeveloped land needed to create long-distance corridors. However, many refuges in the western half of the country are already secure, and management plans from the NWRS would likely be able to keep them connected. Although climate change is rapidly changing habitat and the way it is connected, a concerted management effort around wildlife refuges and all protected areas to create corridors amid housing growth could have a huge impact on maintaining biodiversity.
Hamilton, C. M., M. Baumann, A. M. Pidgeon, D. P. Helmers, W. E. Thogmartin, P. J. Heglund, and V. C. Radeloff. 2016. Past and predicted future effects of housing growth on open space conservation opportunity areas and habitat connectivity around National Wildlife Refuges. Landscape Ecology. DOI:10.1007/s10980-016-0392-8.