Do natural disturbance regimes provide realistic guidelines for managing

1. Do natural disturbance regimes provide realistic guidelines for managing early-successional habitats in New England forests? 

2. Major forest types in northern U.S. Lull (1968)

5. ~1880

6. >50% of forest vertebrates utilize early-successional stands ~1930

8. Obligate users 1.0 RELATIVE USE 0.5 0 10 20 30 40 50 60 70 80 90 100 AGE OF STAND

9. Golden-winged warbler USGS

10. FOREST MATURATION FARM ABANDONMENT Relative abundance of early-successional habitats FOREST CLEARING RETURN TO PRE-COLUMBIAN CONDITIONS ?

11. How much was there?

12. source: Harvard Forest

13. Methods to Estimate Natural Disturbance RegimesLorimer and White (2003) • Sedimentary pollen and charcoal • Presettlement land surveys • Descriptions by early naturalists • Reconstruction of disturbance history in old-growth stands • Modern records and aerial photos • Computer models

14. Large-scale fires infrequent in New England, ~800-1,200 years 1790 survey in NY found that 1% of landscape burned or open.

15. Small-scale wind storms: kill one to several trees. In eastern U. S., 0.2- 2%/year of all forests are affected by wind throw. At any time, 5-50% of a forest may be affected.

16. Large-scale wind storms: hurricanes or tornadoes at irregular intervals (1635, 1788, 1815, 1938, and 1944). 1938 hurricane affected >240,000 ha in New England Boose et al. (2001)

17. >380 yr 380 yr 150 yr 85 yr Approximate return interval of damaging (F2) hurricanes in New England. Boose et al. (2001)

19. Wilson 2005 Lumber Exports (Wilson 2005) vs Witness Trees Projections (Lorimer 1977): very different estimates of the prominence of white pine (>10x), indicating a large difference in the frequency and scale of disturbance in these forests.

20. Northern Hardwoods seedling/sapling (1-15 yrs): 1-3% young pole (15-30 yrs): 1-3% 2-6% Pitch Pine- Scrub Oak seedling/sapling: 10-30% young pole: 10-30% 20-60% (Lorimer and White 2003)

21. 9% 4% Early-successional forests in the eastern U.S. Trani et al. (2001)

22. What AboutBiotic Disturbances?

23. Contemporary Herbivores

24. flooded forest pond wet meadow shrubs forest

25. How large an area affected? 1940: 1% of area 1986: 13% of area Open water areas created by beaver dams on the Kabetogama Peninsula, northern MN. Johnston and Naiman (1990)

26. Northern Hardwoods seedling/sapling 1-3% young pole 1-3% (Lorimer and White 2003) beaver flowages ~3.5% (Gotie and Jenks 1982) 5-11%

27. Even if we can accurately estimate HRNV, are these values relevant in contemporary landscapes?

28. POPULATION DENSITY 40/mi2 1100/mi2

29. Road Density in the Northeast Hoving (2001)

34. 100 140 120 RACCOONS 80 100 60 80 COMPOSITION (%) LANDSCAPE RACCOON/CANID TRACKS 60 40 40 CANIDS 20 AGR 20 FOR DEV 0 0

35. 69% 35% Patches  2.5 ha  5 ha Winter mortality:

36. CONDITION-SENSITIVE PREDATION LARGE PATCHES SMALL PATCHES FOOD QUALITY THRESHOLD? OCT NOV DEC JAN FEB MAR APR MAY

37. 12 10 3 3 4 8 6 3 5 4 5 3 6 6 UN:C RATIO 2 13 13 2 12 4 11 13 5 2 8 4 8 5 7 9 5 7 4 5 0 9 JAN 6 FEB 3 APR 6 MAR 30 JAN 13 FEB 27 FEB 20 FEB 16 JAN 23 JAN 10 APR 13 MAR 27 MAR 20 MAR

38. New approaches needed to provide habitat

39. old Forest Age young limited extreme potential to mimic natural disturbances modified disturbances (large and clustered/connected) restoration of shrublands/ modified disturbance regime (“sliding scale”) Parcelization or Fragmentation

40. ME VT NH NY MA CT RI MANAGING INDUCED METAPOPULATIONS: may require deviating from HRNV

44. DESCRIBING HABITAT DISTURBANCES Size Intensity Frequency

46. Do natural disturbance regimes provide realistic guidelines for managing early-successional habitats in New England forests? 

48. Human-generated disturbances

49. Pisgah Forest in southwestern New Hampshire three years after 1938 hurricane.