Ferruginous hawk demography in areas differing in energy extraction activity

Abstract

ABSTRACTThe recent expansion of oil and gas extraction activity on the Great Plains, USA, has occurred with little understanding of potential effects of the activity on wildlife populations. We monitored the demography of breeding ferruginous hawks (Buteo regalis) in 2 areas of western North Dakota, USA, subject to different intensities of energy extraction. Northwestern North Dakota is the heart of the Bakken Shale, where oil and gas extraction activity has been intense (e.g., 1,273 new oil wells from 2011–2013 in our high‐intensity study area) in recent years. In contrast, such activity has occurred at a relatively low intensity (e.g., 18 new oil wells from 2011–2013 in our low‐intensity study area) in southwestern North Dakota. Ferruginous hawks in the 2 areas had similar densities of nesting pairs, with comparable fledging success. However, between‐year re‐use of nest sites was significantly lower in the area with high‐intensity energy extraction (1 of 8) than the area of low‐intensity (8 of 10); also, re‐use of nests in the high‐intensity area was considerably lower than reported from other parts of the range of the species. Thus, although high‐intensity energy extraction activity had no apparent impact on immediate reproductive success of ferruginous hawks, long‐term population declines could be expected in our northern study area given the unusually low rate of nest‐site re‐use. © 2016 The Wildlife Society.