
Empidonax traillii extimus
Habitat: Riparian; elevation below 8,500 feet
Survey Window: May 1–Jul 31
• May: 1 diurnal survey; June: 2 diurnal surveys; July: 2 diurnal surveys
• Five-day minimum interval between any survey
• When surveying for both southwestern willow flycatcher and least Bell’s vireo, separate surveys must occur with flycatcher surveys performed first