Impacts of wind turbines on redheads in the Laguna Madre

Abstract

Freshwater 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.

Band Wear and Effects on Recovery and Survival Estimates of Diving Ducks

“…Our study was not able to determine causation of band wear, but differences in band wear between lesser scaup and redheads suggest that factors in addition to salinity are important in determining whether a banded species might exhibit excessive band wear. We were surprised to find that redhead, a species using predominantly hypersaline habitats during winter would experience band wear rates roughly half as much as lesser scaup, a species wintering in a variety of fresh and saline environments (Adair et al 1996, Herring and Collazo 2005, Lange 2014, Lange et al 2018).…”

“…Our study was not able to determine causation of band wear, but differences in band wear between lesser scaup and redheads suggest that factors in addition to salinity are important in determining whether a banded species might exhibit excessive band wear. We were surprised to find that redhead, a species using predominantly hypersaline habitats during winter would experience band wear rates roughly half as much as lesser scaup, a species wintering in a variety of fresh and saline environments (Adair et al 1996, Herring and Collazo 2005, Lange 2014, Lange et al 2018. We observed considerable variation in band wear between lesser scaup and redheads, with band wear especially pronounced in lesser scaup; only 29.2% of aluminum bands recovered from double-banded lesser scaup had contact information that would be considered fully functional (i.e., none of the inscriptions were missing).…”

Estimating offsets for avian displacement effects of anthropogenic impacts

“…Independent of habitat loss, energy development may also cause lowered avian reproductive success (Mahoney and Chalfoun , Yoo and Koper ) and alteration of hydrology that can impact waterfowl abundance (Lange et al. ).…”

“…Impacts to grassland birds from reduced patch size and increased edge inherent to grassland fragmentation result in lower avian abundance and reproductive success, such as complete abandonment of nests or increased predation of eggs, nestlings, or adults, as well as increased brood parasitism (Bakker et al 2002, Herkert et al 2003, Davis et al 2006, Sliwinski and Koper 2012. Independent of habitat loss, energy development may also cause lowered avian reproductive success (Mahoney andChalfoun 2016, Yoo andKoper 2017) and alteration of hydrology that can impact waterfowl abundance (Lange et al 2018).…”

“…Energy development is also responsible for the behavioral avoidance, or displacement, of birds from suitable habitat near energy infrastructure; displacement has been found in several taxonomic groups that rely on grasslands for breeding habitat, including waterfowl (Winkelman 1992, Lange et al 2018, passerines (Johnson et al 2000, Thompson et al 2015, Shaffer and Buhl 2016), shorebirds (Pearce-Higgins et al 2012, Sansom et al 2016, raptors (Pearce-Higgins et al 2009, Garvin et al 2011, and upland game birds (Winder et al 2014, Dupuie 2018. Behavioral displacement is typically measured as a decrease in avian density measured over distance from energy infrastructure (sensu Shaffer and Buhl 2016).…”