1 / 21

Arizona

Arizona. New Mexico. Flagstaff. Albuquerque. Phoenix. Tucson. Arizona. New Mexico. Methods. 3-min passive survey 3-min call-broadcast survey 2021 points 115 survey routes 200 m spacing 0600-1100 h. Coverage and Analyses. 9 mountain ranges

louvain
Télécharger la présentation

Arizona

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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

More Related