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Arizona PowerPoint Presentation

Arizona

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Arizona

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  1. Arizona New Mexico Flagstaff Albuquerque Phoenix Tucson

  2. Arizona New Mexico

  3. Methods • 3-min passive survey • 3-min call-broadcast survey • 2021 points • 115 survey routes • 200m spacing • 0600-1100 h

  4. Coverage and Analyses • 9 mountain ranges • replicated 1980-83 and 1995-96 surveys • detected 56 flycatchers • regress year vs # BBFLs for each route • meta-analysis to test Ho: trend  0

  5. Estimating detection probability p=(pvocal).(pobs) • focal bird trials (n=93) • focal nest trials (n=8) • double sampling (n=15 canyons)

  6. Effects of fire on BBFL distribution 1. burned vs non-burned paired surveys <10 year-old fires only areas with no records of BBFLs 2. BBFL presence correlated with fire

  7. Fire Index 0 - no evidence of fire 1 - low-intensity ground fire 2 - medium-intensity ground fire 3 - high-intensity ground fire 4 - high-intensity crown fire 5 - old, high-intensity crown fire

  8. BBFLs have declined in 13 of 19 canyons in SE Arizona since 1995 b = -0.51 df = 18 P = 0.04

  9. Detection Probability • focal bird trials (pvocal) • 92% • focal nest trials • 75% at 100m • 100% at50m • double sampling • 78%

  10. Call broadcast increased detection probability of BBFLs by 49% t = 3.3 P = 0.02 more calls, more visuals more songs

  11. But, call broadcast decreased detection probability of 97% of the co-existing birds by an average of -25%

  12. Surveys may need to be longer than 6 min.

  13. BBFLs detected across wide range of elevations

  14. Effects of fire

  15. 0 BBFL detected 0 BBFL detected

  16. BBFLs associated with burned woodlands

  17. Buff-breasted flycatchers more common in burned woodlands F = 7.3 P = 0.007

  18. If BBFLs like burned woodlands and fire suppression = population declines, why no BBFLs in burned canyons? • lack of local recruitment? • lack of emigrants from Mexico?

  19. Arizona New Mexico