Land Management and Bird Conservation at the Audubon Nature Center and Birds of Vermont Museum (12/06)

By Steve Hagenbuch

If you are one of the thousands of people who own property in Vermont, the Green Mountain Audubon Center/Birds of Vermont Museum Important Bird Area (GMAC/BOVM IBA) in Huntington can be a resource to assist you in managing your property for wildlife, even though your objectives may also include producing forest and agricultural products, developing trails for outdoor recreation, or simply enjoying the aesthetic values the land provides. The basis for this new program is a recently completed land management plan for the IBA. As a result, Audubon Vermont (AV) and BOVM staff and volunteers are working together to develop the combined 400 acres as a demonstration site for bird-friendly management practices that simultaneously provide for maple syrup and hay production, outdoor education and recreation, and scientific research. This plan is the most recent collaboration between these two conservation-education organizations located on Sherman Hollow Road.

The Seed is Planted

The process began with a natural and cultural resource inventory conducted in the spring of 2005 by graduate students from the University of Vermont’s Field Naturalist and Ecological Planning programs [see “Green Mountain Audubon Center Becomes a Classroom for ‘The Big Kids’”, The Hermit Thrush, September 2005]. The purpose of the inventory was to obtain a thorough understanding of the ecological and cultural attributes of the property. In working with UVM on this project, AV and BOVM remained true to their mission of providing educational experiences for students of all ages. At that time, I served as director of the Green Mountain Audubon Center. Now, a year and a half later, the next phase of this project, the creation of a working management plan, has become a part of my own education. Having left my post with Audubon Vermont to pursue a master’s degree in conservation biology at Antioch University New England in Keene, NH, I was fortunate to be able to integrate the development of the plan into my own studies.

To kick off the land management plan development process, the boards and staff of the Green Mountain Audubon Society, Audubon Vermont, and Birds of Vermont Museum met in March. Prominent Vermont maple sugar maker and consulting forester, Dave Marvin, of Butternut Farm, was guest speaker and gave his perspective on forest management planning in Vermont. Armed with Mr. Marvin’s insights and the inventories conducted by the UVM students, Audubon Vermont conservation biologist Mark LaBarr, Birds of Vermont Museum biologist Erin Talmage, and I met to outline the overall goal and specific objectives for land management of the IBA. We considered the current condition of the landscape and what it is capable of providing in the future, as well as current and projected educational and scientific programs. The outcome of this process was the following statement:

The goal of land management at the Green Mountain Audubon Center / Birds of Vermont Museum Important Bird Area is to maintain and/or enhance a diversity of habitat types for wildlife, with a focus on Audubon Vermont’s “Birder’s Dozen”, thereby creating opportunities for scientific research, environmental education, demonstration of bird-friendly land management practices, production of agricultural and forest products, and outdoor recreation.

The “Birder’s Dozen” is a component of Audubon Vermont’s Forest Bird Initiative [see “Audubon Vermont’s Forest Bird Initiative” by Bruce MacPherson, The Hermit Thrush, September 2006]. This list of 12 Vermont forest birds serves as a surrogate for a more extensive list of 39 species that Audubon Vermont has recognized as responsibility species, those for which the forests of the Green Mountain State play a globally significant role. The Green Mountain Audubon Center/Birds of Vermont Museum IBA has the wonderful opportunity to serve as a site where the land is managed to enhance the habitat for many of these species, and subsequently demonstrate those management practices to other owners of forestland.

Why a Managed Landscape?

A common view is that an unmanaged landscape is most beneficial to wildlife. While this is true in some situations, letting “nature take its course” would be detrimental to many species if it were the only practice. This is not to imply that nature does not know how to take care of itself, or that humans must dominate. On the contrary, the need for management today is frequently the result of other influences humans have on the landscape.

Prior to European settlement in the 18th century, natural forces were the primary shapers of the landscape. Habitat for all native wildlife was continuously created in a shifting mosaic as natural disturbance was followed by the stages of succession. The result was a patchwork of open habitats and young and old forest. Many of the actions that created open areas and young forest are no longer at work, traditional Native American slash and burn agriculture being a major example; and while they are still abundant, the activities of beaver are greatly restricted. Disturbance due to wind and disease still exists, but at a very different scale and frequency from the past. The greatest form of disturbance today is the conversion of forest, field, and wetland to residential and commercial use, taking the affected areas out of use altogether, both for forestry and agriculture, and for wildlife habitat.

The results of this shift in landscape dynamics on biodiversity are evident. For the first time since European settlement, populations of wildlife species dependent upon early-successional habitats are declining throughout the northeast, as the young forests that resulted from agricultural abandonment and other land clearing mature. Bird species that rely upon early-successional forests are habitat specialists. They have a narrow range of tolerance of habitat conditions, and are able to occupy a site for only a few years after a significant disturbance event before the habitat becomes unsuitable for nesting and/or feeding. Future success of these species may be dependent on active conservation and management efforts. Meanwhile, populations of some species adapted for late-successional forest habitats are increasing. Bird species such as Red-eyed Vireo and Ovenbird, are able to remain in a maturing site more than ten years. The opportunity before us is to reestablish the mosaic of habitat types to the scale that once existed. Active land management that mimics natural disturbance is our tool to take advantage of this opportunity.

Bringing it all back home

Today’s Green Mountain Audubon Center/Birds of Vermont Museum Important Bird Area provides an excellent example of a diverse landscape. It is often referred to as a “microcosm of Vermont”, for many of the landscape features that one can identify while looking down on the state from an aircraft can also be found at the IBA: northern hardwood and hemlock forests, a fast-moving river and stream, various types of wetlands including a beaver complex, agricultural fields and meadows, and an active sugarbush. The current landscape provides a mosaic of habitat types, and consequently a diversity of wildlife. Maintaining this diversity will be dependent upon continuation of current practices such as haying, brush hogging of some fields, and management for sugaring, and natural disturbance, or human activity that mimics natural disturbance. The completed land management plan for the IBA will be used to guide on-the-ground efforts to achieve this goal. The plan recommends the following overarching management guidelines over the next 10 years:

The IBA currently provides early-successional habitat in a number of places. Management to maintain it where it currently exists is recommended. Opportunities to create new early-successional habitat also exist. These are sites where there is a transition from forest to field, field to pond, and forest to pond. As beavers continue to cycle through the landscape, their abandoned ponds will also develop into early-successional habitat.
Forests of various age-classes comprise a large percentage of the IBA. A dense canopy is characteristic of many of these forests. Under this dense canopy, the forest floor is shaded for most of the growing season, limiting variety in vertical structure by suppressing shrubby and herbaceous growth. A forest with a diversity of vertical structure provides suitable nesting and foraging habitat for a greater number of bird species, including many of those on the responsibility list. To promote this type of vegetative growth, single-tree and small-group harvests that mimic natural disturbance are recommended in selected areas to provide canopy gaps that will permit sunlight to reach the forest floor, and support the development of shrub and herbaceous layers.
Beaver have been influencing the IBA landscape for decades. Their activity has led to an extensive wetland complex. Management efforts that allow them to persist while at the same time minimizing the potentially negative impact of their activity (trail flooding, felling of maple sugaring trees) are recommended. This can be achieved through installation of water control devices in the beaver dams and by wrapping maple trees with wire mesh.
Forest and agricultural products are important to the economy and heritage of Vermont. Two such products, maple syrup and hay, are currently harvested from the IBA. Management that concurrently provides these products and maintains or enhances the ecological value of the forests and fields from which they are derived is recommended.
No-management is management. A number of locations across the IBA will be left unmanaged, allowing natural processes to occur without human influence. These areas will serve as a “control” in comparison to actively managed areas.

Close to 80% of the Vermont landscape is privately owned. This gives thousands of individuals and families the opportunity to contribute to the conservation of wildlife through their management actions. Collectively our efforts will go a long way toward the conservation of Vermont’s natural heritage. Everyone is invited to visit the Green Mountain Audubon Center/Birds of Vermont Museum Important Bird Area to see first hand some of the ways we can achieve this goal.