Willow Flycatcher winter habitat in El Salvador, Costa Rica, and Panama: Characteristics and threats

The Willow Flycatcher (Empidonax traillii) spends more than half the year on wintering grounds from central Mexico to northern South America, yet there is little detailed information about Willow Flycatcher winter distribution and habitat use. We surveyed for wintering Willow Flycatchers in El Salvador, Costa Rica, and Panama during January and February of 1998-2000. Our objectives were to locate and describe occupied Willow Flycatcher winter habitat and identify possible threats to wintering flycatchers and their habitats. We detected 542 wintering Willow Flycatchers distributed among 28 survey locations. The majority of occupied winter Willow Flycatcher habitat was found along the Pacific lowlands below 250 m, and contained four main habitat components: standing or slow moving freshwater and/or saturated soil; patches and/or stringers of trees; woody shrubs; and open areas, Large and small-scale agricultural activities and/or cattle ranching were present near most occupied sites, resulting in a matrix of relatively small and fragmented patches of suitable wintering habitat within a larger agriculture-dominated landscape.