Effects of Selected Forest Management Practices on Forest Birds in Missouri Oak-Hickory Forests

1. Effects of Selected Forest Management Practices on Forest Birds in Missouri Oak-Hickory Forests

2. Principal Investigators • Rick Clawson, Missouri Department of Conservation • Dr. John Faaborg, University of Missouri-Columbia • Dr. Paul Porneluzi, Central Methodist University

3. Collaborators • Wendy Gram, Sam Noble Oklahoma Museum of Natural History • Mike Wallendorf, Missouri Department of Conservation • Elena Seon, Missouri Department of Conservation (former employee)

4. Background • Studies had shown that avian species diversity and reproductive success were lower on forest fragments • Nest predation by mammalian and avian predators and parasitism by Brown-headed Cowbirds were the principal mechanisms • Some people believed that similar phenomena would occur in a predominantly forested landscape with small openings • An experimental approach was needed

5. Objectives • To determine differences in breeding densities of selected a) mature forest and b) early-successional forest songbirds in forest managed by EAM, UAM, and no-harvest methods • To determine rates of nest parasitism, nest predation, and reproductive success for these songbirds • To provide educational training in field biology to undergraduate student interns

6. 5 Focal Mature Forest Species • Acadian Flycatcher • Ovenbird • Worm-eating Warbler • Kentucky Warbler • Wood Thrush

7. 6 Focal Early Successional Spp. • Indigo Bunting • Yellow-breasted Chat • Hooded Warbler • Prairie Warbler • Blue-winged Warbler • White-eyed Vireo

8. Bird Study – Data CollectionSpot Mapping • Species’ densities determined using spot-mapping • Each site divided into 7 spot mapping plots • Each spot mapping plot surveyed 10 times • Territories identified from compilation maps for each species, each year • Density determined by dividing number of territories by study site area

14. Bird Study – Data Collection (cont.)Nest Monitoring • Reproductive data collected by locating and monitoring nests • Most nests were on the ground, in shrubs, or in the subcanopy • Nests monitored every 3 – 5 days • Predation and parasitism events noted

18. Bird Study – Data Collection (cont.) Mist Netting • 13 mist net lies per study area • 12 mist nets per line, set 50 meters apart • Each mist net line run for two mornings • All captured birds identified, sexed & aged, banded, and released • Prior to first treatment, mist net lines spaced out along east-west grid lines • After treatment, net lines on EAM sites set in clear cuts

20. Results – Spot Mapping • 53 different species recorded • Most species present during both pre-treatment and post-treatment years • Following treatment, all 5 focal mature forest species declined • Early successional species densities increased dramatically after tree harvest • Responses were species specific

21. After initial decline, returning to near pre-treatment levels

22. Climbing, but not yet back to pre-treatment levels

23. Negatively affected by EAM

24. Has returned to pre-treatment level on EAM sites, but abandoning no-harvest sites?

25. Although low numbers, positive response to EAM & UAM

26. Appears to prefer the larger openings of EAM sites

27. Appears to prefer larger openings of EAM sites

28. Accepts all sizes of canopy gaps

29. Accepts all sizes of harvest openings

30. Found in low numbers – responded to both harvest types

31. Results - Nesting • Found over 1,500 nests from 29 species • Found nests for 6 of the focal species, before and after treatment • Daily mortality rates did not change significantly from pre- to post-treatment • Mayfield nesting success averaged 29% for these 6 spp. • Brood parasitism rates were low, averaging 3.2% in both pre- and post-treatment • Nest failure generally attributed to predation

32. Results - Mist Netting • Prior to treatments, capture rates were low on all sites • Recapture rates were low (< 10%) • Nets placed at the edges of clear cuts and on paths in the interior of clear cuts had dramatically higher capture rates • Within clear cuts, both early successional and mature forest birds were captured

33. Implications • In general, forest management treatments affected bird species as expected • Mature forest species declined on all sites • Birds had species-specific responses to even-aged and uneven-aged forest management • Although early successional species increased, some used larger openings and some used both small and larger openings • Recommend a blend of harvest types to maintain diversity of forest avifauna

34. Our results agree with current theory about landscape-level forest cover – the timber-management treatments did not increase cowbird parasitism or nest predation

35. Additional Findings • During the fledging period, even mature forest species moved into the dense vegetation of clear cuts, presumably for foraging and cover • Densities of early successional species were higher in larger clear cuts than in smaller ones • Densities of early successional species apparently reached plateaus in 2000 or 2001 and are now declining

36. Progression of Study • 1991-1996 & 1997-2000 – original protocol • ~ 27 student interns • All 7 spot map plots • 2001-2003 – modified protocol • ~ 16 student interns • 4 of the 7 spot map plots • 2004 • 5 student interns • Point counts rather than spot mapping • 2005-2007 • REU grant & return to modified protocol (?)

37. EAM sites – 1991-2002/4 of 7 plots

38. UAM sites – 1991-2002/4 of 7 plots

39. Challenges • Recruitment of interns was more difficult as time progressed • Downed material and explosive growth in the clear cuts made the interior impenetrable until “bird paths” were cut • We are trying to find funding to continue monitoring avifauna changes between treatment applications

40. Future Avian Study • Continue to monitor avian population dynamics between treatments • Analyses of avian response to clear cuts and the zone immediately surrounding the cuts • Analyses of avian response to TSI • Correlation of bird densities with insect data