Date of this Version
The Prairie Naturalist • 50(2): December 2018
Wilson’s phalarope (Phalaropus tricolor; Scolopacidae) is a migratory shorebird that relies on interior wetlands for foraging and breeding (Colwell and Jehl 1994, van Gils et al. 2018). Its global population status is unclear (Colwell and Jehl 1994, Lesterhuis and Clay 2010), and is variously listed as declining (Morrison et al. 2006, van Gils et al. 2018), increasing (Andres 2009, BirdLife International 2018), and exhibiting a long-term decline but recent stability (Sauer et al. 2011, Andres et al. 2012). Its global population estimate of 1.5 million birds has not been updated for 30 years, since 1988 (Colwell and Jehl 1994, Lesterhuis and Clay 2010, Andres 2012). In Nebraska, analysis of Breeding Bird Survey data indicate a population decline in Wilson’s phalarope by ~1.5% between 1966 and 2014 (Sauer et al. 2017).
Published maps of the breeding range Wilson’s phalarope vary but typically include north-central and northwestern Nebraska as its easternmost extent (Sauer et al. 2017, Silcock and Jorgensen 2018, van Gils et al. 2018, but see also Colwell and Jehl 1994). Their historic breeding range has contracted due to the conversion of native grasslands and wetlands to agriculture (Lesterhuis and Clay 2010), but in recent decades their breeding range has also expanded, particularly eastward (van Gils et al. 2018), presumably as birds search for suitable new habitat. In contrast to most other shorebirds, Wilson’s phalaropes forage mainly while swimming and thus require close proximity to wetlands at all stages of their life cycle (Lesterhuis and Clay 2010). They are considered highly vulnerable to drought and other climate variables (Lesterhuis and Clay 2010, Galbraith et al. 2014), and recent climate modeling predicts a 100% loss of their current breeding range by 2080 due to global warming (National Audubon Society 2015).