Changes in the Breeding Distribution of Buff-breasted Flycatchers in the Southwestern United States: The Role of Fire Su

1. Changes in the breeding distribution of Buff-breasted Flycatchers in the southwestern United States: the role of fire suppression. Chris Kirkpatrick & Courtney J. Conway USGS Arizona Cooperative Fish and Wildlife Research Unit, University of Arizona

2. Pablo Leautaud

3. Thanks to: Field Assistants: Dominic LaRoche, Mike Schroff, Eli Rose, Kelly Bergstram, Brian Powell, and Mark Zepp Logistical Support: Natasha Kline, Don Swann (Saguaro National Park), Josh Taiz (U.S. Forest Service), Bob Peterson (University of Arizona), Shelly Danzer, and Sheridan Stone (U.S. Department of Defense) Bird Photography: Bruce Taubert and Tom Grey

4. Empidonax fulvifrons

6. Arizona New Mexico from Bowers & Dunning (1994)

7. from Conway and Kirkpatrick 2007

8. 91% reduction in U.S. breeding range from Conway and Kirkpatrick 2007

11. 99% reduction in U.S. breeding range

12. 15% reduction in total breeding range Arizona New Mexico from Bowers & Dunning (1994)

13. What is current population trajectory? 9 highest sky island mtn ranges

14. 71 surveys in Huachucas & Chiricahuas ARIZONA NEW MEXICO • TUCSON MEXICO

15. 44 surveys in 7 adjacent mt. ranges • Replicated 1980-83 & 1995-96 surveys ARIZONA NEW MEXICO • TUCSON MEXICO

16. Point-count surveys • At 200 m intervals along • each survey route • From April to July • 3-min. passive period • 3-min. broadcast period

17. Regress year vs # BBFLs for 23 routes • Test Ho: average slope  0 # BBFLs Detected

18. BBFLs have declined on 16 of 23 routes bavg = -0.105 P = 0.061 # BBFLs Detected

19. BBFLs have declined on 16 of 23 routes bavg = -0.105 P = 0.061 Carr Canyon # BBFLs Detected

20. What’s happened to BBFLs in the U.S.? Fire suppression implicated…

21. Coniferous forests in the SW historically subjected to low-severity fires ~1x/decade From Swetnam and Betancourt 2003

22. 1909 1949 1992 From Covington and Moore 1994

23. Increase in understory fuel loads has contributed to recent increase in frequency of wildfires in Southwest “Recent” Fires from Swetnam and Betancourt 2003

24. If observed declines in BBFLs are due to decreased fire frequency, then…. • 1) Recently burned forests more likely to be colonized by BBFLs • 2) Survey points with BBFLs more likely to have evidence of recent fires • 3) Survey points with BBFLs more likely to have evidence of more frequent fire events

25. If observed declines in BBFLs are due to decreased fire frequency, then…. • 1) Recently burned forests more likely to be colonized by BBFLs • 2) Survey points with BBFLs more likely to have evidence of recent fires • 3) Survey points with BBFLs more likely to have evidence of more frequent fire events

26. no BBFLs detected 5 recently burned survey routes 1 pair of BBFLs detected 5 unburned survey routes

27. Potential Problems: • Severity of fires was low • Sample size of survey routes was small

28. If observed declines in BBFLs are due to decreased fire frequency, then…. 1) Recently burned forests more likely to be colonized by BBFLs 2) Survey points with BBFLs more likely to have evidence of recent fires 3) Survey points with BBFLs more likely to have evidence of more frequent fire events

30. Burn Severity Index (5 classes): 0 1 2 3 4 • 0) no evidence of fire • low-severity surface fire • moderate-severity surface fire • high-severity surface fire • high-severity crown fire • Modified from Ryan & Noste 1985

31. Buff-breasted flycatchers more common in burned woodlands Burn Severity Class

32. Percent cover of vegetation at 4 heights differed among 5 burn-severity classes Burn-severity Class

33. Potential Problem: 1) Burn-severity index provides information on severity but not frequency of previous fire events

34. If observed declines in BBFLs are due to decreased fire frequency, then…. 1) Recently burned forests more likely to be colonized by BBFLs 2) Survey points with BBFLs more likely to have evidence of recent fires 3) Survey points with BBFLs more likely to have evidence of more frequent fire events

35. 1916 Fire 14 survey routes without BBFLs 14 survey routes with BBFLs 1865 Fire 1842 Fire

36. Routes with BBFLs had more frequent fires tpaired = 1.8 P = 0.048 with BBFLs without BBFLs

37. Potential Problems: 1) not all trees scar during a fire 2) don’t know the severity of previous fires

38. Summary of results Fire frequency Fire severity

39. Why didn’t BBFLs colonize our 5 recently (<10 yrs) burned survey routes? 1) recruitment and immigration insufficient? 2) low-severity burns insufficient? 3) BBFLs may require >10 years to locate and colonize burns

40. Why didn’t BBFLs colonize our 5 recently (<10 yrs) burned survey routes? 1) recruitment and immigration insufficient? 2) low-severity burns insufficient? 3) BBFLs colonize areas >10 yrs post-burn?

41. Conducted surveys in 7 mt. ranges • adjacent to Huachucas & Chiricahuas Last BBFL recorded 18 Aug. 1911 We detected: 2 in 2000 4 in 2004 5 (incl. pair) in 2005 MEXICO

42. What’s driving BBFLs to re-colonize the Rincon Mountains after 89 year absence? Tucson Mica Mt 70% of bird survey points burned (56% burned severely) Ignitions and Fire History, Rincon Mountains, Saguaro National Park Ignition Points Rincon Peak Burn Perimeters

43. Carr Canyon <1976 4 1976 Fire 1983 9 1995 17 2004 23

44. Santa Catalina Mountains Bullock Wildfire (2002) & Aspen Wildfire (2003)

45. Santa Catalina Mountains >90% burned Variation in burn severity

46. Future work • Continue monitoring BBFL populations in Arizona (and New Mexico?) • Determine reproductive success to assess quality of habitat • Determine status of Mexican population

47. For more information: Conway, C. J., and C. Kirkpatrick. 2007. Effect of forest fire suppression on buff-breasted flycatchers. Journal of Wildlife Management 71:445-457. Kirkpatrick, C., C. J. Conway, and D. LaRoche. 2007. Range expansion of the Buff-breasted Flycatcher (Empidonax fulvifrons) into the Rincon Mountains, Arizona. Southwestern Naturalist 52: 149-152. Kirkpatrick, C., C. J. Conway, and P. B. Jones. 2006. Distribution and relative abundance of forest birds in relation to burn severity in southeastern Arizona. Journal of Wildlife Management 70:1005-1012.

48. For more information: www.ag.arizona.edu/srnr/research/ coop/azfwru/cjc/ • click on links to “Research” and “Past Project #8” and “Past Project #9” kirkpatr@email.arizona.edu