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High-elevation Spruce-Fir Forest in the Northern Forest: An Assessment of Ecological Value and Conservation Priorities Principal Investigator: Dr. David Publicover Affiliation/Institution: Appalachian Mountain Club Email: [email protected] Mailing address: PO Box 286, Gorham, NH 03581 Co-Principal Investigators: Dr. Kenneth Kimball Affiliations/Institutions: Appalachian Mountain Club Emails: [email protected] Completion date: spring 2013 High-elevation areas are a limited yet critical component of the Northern Forest landscape. Despite a high level of conservation, ecologically significant areas remain unconserved, especially in Maine. Funding support for this project was provided by the Northeastern States Research Cooperative (NSRC), a partnership of Northern Forest states (New Hampshire, Vermont, Maine, and New York), in coordination with the USDA Forest Service. http://www.nsrcforest.org Project Summary High-elevation habitats are a limited yet critical component of the Northern Forest landscape. They provide the primary habitat for Bicknell’s thrush, the northeast’s rarest migratory songbird, as well as other species of conservation concern. They are also likely to provide refugia for spruce-fir-dependent species in a future warmer climate. These areas have been a target for wind power development, but inappropriately sited wind power projects threaten to degrade this critical habitat. Evaluation, prioritization and conservation of the most important areas is an objective of many state and regional wildlife conservation plans. This project is assessing the extent, conservation status, current condition (development and harvest history) and relative ecological value of high-elevation areas (>2700’) across New York and New England to guide future conservation of these areas and reduce conflicts over wind power siting. Information on ecological value includes elevation range, extent of spruce-fir forest, presence of rare plants and natural communities (particularly subalpine fir- heartleaved birch forest), documented presence of Bicknell’s thrush and extent of potential Bicknell’s thrush habitat, inclusion in large roadless areas, and identification as priority areas in state wildlife action plans and other regional conservation assessments. There are about 767,000 acres of high-elevation land in ME, NH, VT, MA and NY, or about 1.2% of the area of these five states, with 60% lying within 39 areas greater than 5,000 acres in size. Overall the level of conservation is high relative to other parts of the landscape, with over 83% of high-elevation land under some form of permanent conservation. Maine is the outlier with less than half of its high-elevation land conserved. Though high-elevation areas are in general the most “natural” parts of the landscape, significant impact from development and harvesting has occurred in some areas. Nearly 10% of the areas over 10 acres in size have some form of development, including three commercial wind power projects, 34 downhill ski areas encompassing over 1% of the total area of high-elevation land, and public roads and summit complexes on some of the region’s most notable mountains. Nearly 4% of the area shows evidence of harvesting since 1975, with most of this concentrated on large commercial ownerships in northern New Hampshire and western Maine (where nearly 20% of the private high- elevation land has been harvested over this time). The most important high-elevation area with a relatively low level of conservation is the Sugarloaf-Abraham- Crocker area in western Maine – at nearly 21,000 acres the largest high-elevation area in the state containing multiple significant ecological values. Though only 22% of the area is conserved, the area is the focus of on-going conservation attention with multiple projects underway. The greatest concentration of unconserved high-elevation land is the northern Boundary Mountains region of western Maine, which has high value as Bicknell’s thrush habitat. Background and Justification • High-elevation areas (>2700’) are a limited component of the northeastern landscape but provide significant ecological values. • They are generally the most “natural” parts of a regional landscape that has been heavily impacted by human use (settlement, agriculture, timber harvesting). • These areas provide important habitat values as well as having significant adaptive value in a changing climate. • Mountain areas have long been a focus of conservation attention (e.g. Adirondack, Catskill, and Baxter state parks, Green Mountain and White Mountain national forests). While the overall level of conservation is high, significant areas remain unconserved. • High-elevation areas have been a target for commercial wind power development, which if inappropriately sited can degrade the values of these areas. • A comprehensive assessment of the conservation status, condition and ecological value of high-elevation areas across the region will help identify the most important unconserved areas, serving as a guide for future conservation action and appropriate siting of wind power projects. Background and Justification (cont.) Habitat value of high-elevation areas: • High-elevation spruce-fir or subalpine fir forest is recognized as a distinct habitat in state wildlife action plans (ME, NH, VT) as well as regional bird conservation plans (Partners in Flight, Atlantic Coast Joint Venture). • Critical habitat for Bicknell’s thrush, which is endemic to subalpine forest of the northeastern US and maritime Canada. This species has perhaps the most restricted breeding range of any North American bird, has been called “perhaps the highest priority for conservation planning” by Partners in Flight, and is being considered for T&E listing by US Fish and Wildlife Service. • Other species of concern associated with this habitat include blackpoll warbler, spruce grouse, boreal chickadee, white-winged crossbill, three-toed woodpecker, purple finch, olive-sided flycatcher, bay-breasted warbler, northern bog lemming, American marten and Canada lynx. • Many of these plans recommend prioritization and conservation of the most significant areas, with a particular focus on Bicknell’s thrush. • Many of these plans identify commercial wind power development as a threat to this habitat. Background and Justification (cont.) Climate adaptation value of high-elevation areas: • The extent of suitable conditions to support spruce-fir forest in the northeast is expected to decline significantly over the next century, with the range of this forest type contracting to the higher elevation areas of northern New York and New England. • Paleoecological evidence indicates that high-elevation vegetation may be more resistant to climate change than lower-elevation vegetation. During the major post-glacial Hypsithermal warming period (5,000 to 9,000 YBP), the extent of high elevation forests in the White Mountains showed little change during a time when low-elevation spruce-fir forest was greatly reduced. • Recent research by AMC and others on the historic climate of the Presidential Range supports the idea that high-elevation areas in the region are to some degree uncouple from and more resistant to climatic changes occurring at lower elevations. • The projected decline in spruce-fir forest, and its ability to persist at higher elevations in the face of climate change, emphasizes the need to maintain the integrity of high-elevation forests as potential refugia for spruce-fir dependent species. Methods • Areas above 2700’ elevation across ME, NH, VT, MA and NY were delineated using USGS 30-meter Digital Elevation Model data. • Publicly-available data on conservation lands for each state was used to determine the proportion of each area conserved through public ownership, non-profit ownership and conservation easement. • The current condition of each area was determined in two areas: – Development: Existing development was delineated from NAIP aerial imagery and categorized as to type. – Harvest history: Areas showing clear evidence of recent (post-1975) and earlier (pre-1975) timber harvesting were delineated from NAIP aerial imagery and historical aerial and satellite imagery. • Information on a range of ecological values (see next slide) was acquired from publicly-available sources; evaluation of areas for to determine overlap with these values is on-going. • Information on condition and ecological value will be combined into a ranking system to describe the relative conservation value of each area. • A Google Earth application is being developed to present information on these areas in a web-accessible map-based format. Methods (cont.) Information included in assessment of ecological value: • Elevation range. • Proportion of area in spruce-fir forest (from National Land Cover data). • Presence of rare plant and natural community occurrences documented by state Natural Heritage programs. • Presence of documented (from state Natural Heritage program data) or potential (delineated from NAIP imagery) occurrences of subalpine fir-heartleaved birch forest. • Documented occurrences of Bicknell’s thrush (from Vermont Center for Ecostudies Mountain Bird Watch database). • Extent of potential Bicknell’s thrush habitat (from model developed by Vermont Center for Ecostudies). • Proportion of area in large (> 5,000 acre) roadless areas delineated by AMC. • Inclusion of area in state wildlife action plan focus area (ME) or highest value habitat (NH). • Presence of priority summit ecosystems identified in TNC Northern