Molt migration and migratory connectivity of the long‐billed dowitcher

Abstract

ABSTRACTEffective conservation of migratory shorebirds requires information on their stopover ecology and migratory connectivity in areas such as the Great Basin and interior California, USA, where freshwater is highly managed and maintenance of wetland networks requires planning across multiple regions. We captured long‐billed dowitchers (Limnodromus scolopaceus; hereafter dowitchers) to study their molt patterns and length of stay in the Klamath Basin during fall migration and their migratory connectivity and over‐winter space use in California's Central Valley. Most dowitchers were in active primary molt when captured (83%, n = 116), and molt stage increased during August and September. Radio‐tagged dowitchers had an average length of stay after capture of 31.9 days (n = 54). After departing the Klamath Basin, we located 57% of 81 radio‐tagged dowitchers in the Central Valley from December to February; most of the 228 detections occurred in the Sacramento Valley (39%) or Grasslands Ecological Area in the San Joaquin Basin (47%). Space use by radio‐tagged dowitchers differed among the Sacramento Valley, San Joaquin Basin, and Sacramento‐San Joaquin Delta sub‐regions, which demonstrated the influence of varying amounts and distributions of habitat. We recommend that managers in the Klamath Basin provide shallow‐water wetlands to support migrant dowitchers for ≥30 days beginning around 1 August, but ideally wetlands should be maintained until 30 September if freshwater supplies are available. We also recommend coordinated management of shallow‐water wetlands within and between the Klamath Basin and Central Valley to optimize the use of freshwater, a limited and unreliable resource. © 2015 The Wildlife Society.