Impacts of wind turbines on redheads in the Laguna Madre

Abstract

ABSTRACTFreshwater ponds adjacent to the Laguna Madre along the lower Texas coast provide an important and heavily used source of fresh water for the redhead (Aythya americana) throughout winter. A 267‐turbine wind farm was constructed within the core wintering area of the redhead on a private ranch along the western coast of the Laguna Madre, in 2010. Our objective was to investigate the effects of this wind farm on the habitat and potential displacement of redheads and their use of coastal ponds along the lower Texas coast. We conducted weekly aerial surveys to monitor coastal pond use by wintering redheads from mid‐October through mid‐March during pre‐construction (2000–2003) and post‐construction (2012–2014) of the wind farm. Pond availability and Palmer Drought Severity Index (PDSI) within the wind farm were significantly correlated during pre‐construction (n = 16, R2 = 0.53, P = 0.035) and post‐construction (n = 11, R2 = 0.64, P = 0.003). However, the number of ponds available at each PDSI level within the wind farm decreased during post‐construction (paired t = 3.2, n = 5, P = 0.033). The average number of redheads detected per survey on coastal ponds within the wind farm decreased by 77% from pre‐construction to post‐construction. Redhead abundance on ponds across the entire Laguna Madre increased by an average of 3.26 times between pre‐construction and post‐construction, partly due to increases in the continental redhead population. It appears that the wind farm has altered the use of coastal ponds by redheads during winter. Future wind farm placement along the lower Texas coast should consider coastal pond distribution and the dynamics of redhead use between coastal ponds and foraging areas in the Laguna Madre. © 2018 The Wildlife Society.