SUMMARY
Title: Ossipee Fuel Mapping Results and Recommended Fuel Models – Summary
Author: Michael Batcher, Ecologist and Environmental Planner
Abstract: This report summarizes the results of 1) data collected in 34 plots at Ossipee Pine Barrens in 2013 to describe vegetation and fuels, 2) interviews with several prescribed fire practitioners in the northeast and 3) recommendations on fuel models that could be used at Ossipee based on the above information.
A series of reports (below) including reviews of relevant literature, monitoring protocols, and analyses of field data were completed for this study. Full citations are provided in the references sections and copies are available from The Nature Conservancy’s Shawangunk Ridge.
REPORT #1
Title: Analysis of Field Data for the Shawangunks Grassland and Forests Birds Habitat Study- Summary Report
Author: Michael Batcher, Ecologist and Environmental Planner
Abstract: In early 2008, The Nature Conservancy, in partnership with the Mohonk Preserve and the U.S. Fish and Wildlife Service, initiated a series of coordinated research projects to test the efficacy of several management strategies to achieve specific goals for habitat management for both grassland and forest nesting birds. The studies focused on several species listed as Species of Greatest Conservation Need (SGCN) by the New York State Department of Environmental Conservation (Table 1).
In April of 2008, just before initiation of this study, there was a major wildfire in the Overlooks area in Minnewaska State Park Preserve which burned approximately 3,000 acres (1,250 ha) within the Park and some adjacent private lands. This was the largest fire in the Shawangunks since the 1947 wildfire that burned over 7,000 acres (3,000 ha). Given this opportunity, we established both vegetation and bird monitoring plots within the wildfire area and in some unburned areas nearby for comparison. The locations of treatment units and of the wildfire are shown on Maps 1 and 2.
REPORT #2
Title: Analysis of Field Data for the Shawangunks Grassland and Forests Birds Habitat Study – Grassland Management
Author: Michael Batcher, Ecologist and Environmental Planner
Abstract: We established plots and collected data at both the Mohonk Preserve and Shawangunk Grasslands National Wildlife Refuge (SGNWR) to compare management treatments for maintaining open fields at the Mohonk Preserve and grassland bird habitat at SGNWR. We chose a set of variables to measure including shrub cover, grass vs. forb cover, invasive species cover, height density, litter cover and litter depth.
The original, planned treatments included both mid-summer (July) and late summer (September) mow only and mow and burn treatments at SGNWR and the Mohonk Preserve. One field at the Mohonk Preserve was burned in the spring of 2009, but weather and other conditions prevented any other use of prescribed fire. Summer (July) mowing was completed in two of the SGNWR units and September mowing was completed in two of the Mohonk fields. The September mow at SGNWR did not occur. A spring mow was substituted and completed in one field at the Mohonk Preserve.
Optimal grassland bird habitat includes grass as dominating vegetative cover (70%) with forb cover of 10-30%. Management resulted in mixed changes in grass and forb abundance with most treatments increasing forb abundance. Some treatments resulted in increases in grass in one field and decreases in another at the same site. Litter depth and cover remained relatively unchanged, except for a reduction following the spring burn and increases following mowing. As would be expected, height density decreased following treatments. Annual treatments will likely be needed to reduce height density to levels preferable to most grassland nesting birds.
REPORT #3
Title: Analysis of Field Data for the Shawangunks Grassland and Forests Birds Habitat Study – Undercliff Oak Forest Management
Author: Michael Batcher, Ecologist and Environmental Planner
Abstract: As part of a study on the effects of prescribed fire on forest bird habitat, we established 16 plots within a 35.7 acre (14.4 ha) treatment unit in 2009. Target bird species were Black-throated Blue Warbler (Dendroica caerulescens), Scarlet Tanager (Piranga olivacea), Wood Thrush (Hylocichla mustelina) and Worm-eating Warbler (Helmitheros vermivorum), all of which are Species of Greatest Conservation Need (SCGN). We collected data on tree, shrub, sapling and seedling abundance. We also collected data specific to shrub nesting birds by measuring shrub abundance at 0.5 m height increments from zero to three meters. We burned the unit in late April and early May of 2010 and resurveyed all 16 plots.
Both Black-throated Blue and Canada Warblers nest in the dense shrub layers of 1-3 meters that were reduced in height and cover by the prescribed fire. Clearly the fire was not favorable to those habitat characteristics needed for those species. Increases in seedling densities and regrowth of mountain laurel will likely result in suitable habitat again, though we cannot predict the time frame for that from this study. At the same time, there was negligible change in tree density or canopy cover, so some of the appropriate habitat characteristics for these species remain. Scarlet Tanagers require large, unbroken forests with closed canopy, so their habitat requirements remain unchanged. Litter cover remained relatively unchanged, and new litter will fall to replace what was burned. Therefore, habitat for Worm-eating Warblers should also remain relatively unchanged.
The methods used here could be modified for monitoring site treatments, and recommendations are included for both future research and monitoring.
REPORT #4
Title: Analysis of Field Data for the Shawangunks Grassland and Forests Birds Habitat Study – Overlook Wildfire Study
Author: Michael Batcher, Ecologist and Environmental Planner
Abstract: The Overlooks Wildfire burned approximately 1,250 ha within Minnewaska State Park Preserve and some adjacent private lands in April of 2008. This was the largest fire in the Shawangunks since the 1947 wildfire that burned over 3,000 ha. To measure the effects of this fire, vegetation and other data were collected from 96 10-m radius circular plots (314 m2) in Minnewaska State Park Preserve from early June to mid- September of 2008. Fifty-five of these were in burned areas mapped as chestnut oak forest and 20 in nearby, unburned chestnut oak forest. Twenty-one plots were located within burned pitch pine-oak-heath rocky summit. In late May and early June of 2008 bird data was collected from 25 points within the boundary of the Overlooks Wildfire and from 15 points in a nearby, unburned chestnut oak forest. These were also included in the above vegetation plots. To provide further comparison of burned vs. unburned areas, data from 1995-96 mapping of the northern Shawangunks by John Thompson (1996), incorporated into New York Natural Heritage Program data (NHP), were also analyzed.
Forty species of birds were recorded in 2008 in burned areas while 31 were recorded in unburned areas. In 2009, 35 species were recorded in burned areas and 30 in unburned areas. In 2010, 52 species were recorded within the burned area. Changes in mean abundance between burned and unburned areas and between years for birds were inconsistent, both for many individual species as well as for bird guilds. The most consistent findings were for several of the species associated with forests. Ovenbirds, Black-throated Blue Warblers and Black and White Warblers all showed declines from
unburned to burned areas. On the other hand, Scarlet Tanagers were also more abundant in burned areas.
Given the open woodland areas where tree mortality was apparently high and the trajectory of the community toward one dominated by sassafras and red maple, I conclude intervention will be needed to restore the chestnut oak forest in the Overlooks Wildfire area. Leaving the area alone will likely lead to the area stabilizing as a shrubland or a woodland dominated by red maple and sassafras. Fire should be introduced as early a possible to reduce seedling numbers for both of these. Mechanical and herbicide treatments will be needed to reduce sassafras and red maple trees and saplings to reduce seed input. It may even be necessary to distribute acorns in areas where oak density is too low to provide sufficient numbers and where rodents and deer reduce acorns and seedlings. These actions can be incorporated into a program of further research and long-term monitoring of fire effects to track changes resulting from the Overlooks Wildfire. This should be integrated into the prescribed fire program contemplated in the recently completed fire management plan for the Shawangunks.