Habitat Priorities

Surveys

For many of the priority species associated with mountain bogs, we do not have a clear understanding of their current distribution within the state. We must undertake surveys to gather baseline information on the distribution and status of most of these species. (Surveys Priority)

Monitoring

Given the limited availability and number of threats facing mountain bog habitat, considerable effort needs to be expended to determine if populations are increasing, decreasing, or remaining stable.
Monitor amphibian populations to detect incidence of fungal and viral infections (e.g., iridoviruses, chytridiomycosis).
Monitor connectivity of populations separated by fragmentation.
If Beaver activity is detected in nearby streams, monitor to detect problems from flooding or inundation.

Research

Limit application of fertilizers and lime to lawns and fields surrounding wetlands (Somers et al. 2000).
Genetic studies to determine degree of gene flow between populations and to assess overall population health for species restricted to this habitat(i.e., Bog Turtle), given the isolated nature of mountain bogs.
Study amphibian movements to and from breeding habitats and examine upland habitat use (e.g., Ambystomatid Salamanders, Junaluska Salamander, Mountain Chorus Frog).
Investigate minimum hydroperiods needed by priority amphibian species that utilize ephemeral pools and wetlands. Results can be used to determine when supplemental or interventive measures are needed to support breeding periods and metamorphosis during drought periods.
Establish a captive breeding programfor Bog Turtles and work with land conservation partners to identify sites for population augmentation.
Specific bog management needs to include the control of woody encroachment and succession, the maintenance (and where necessary, restoration) of natural surface water and groundwater hydrology (using ditch plugs, temporary dams, level spreaders, or other engineering devices), the restoration of herbaceous vegetation, and the prohibition of taking rare bog-related species (e.g., Bog Turtle).
Use clearing methods that create the least impacts; avoid use of chemicals. Where appropriate, use prescribed burning to control encroachment by hardwoods. If mowing, limit to once a year or less and set blade height between 1 and 2 feet to avoid destroying nesting bird and small mammal habitat.If using heavy equipment, disturb only one patch of the site at a time and minimize ruts and compaction of soils and vegetation to the extent possible (Somers et al. 2000).
If livestock grazing is allowed, limit number of animals to one per acre and allow light to moderate seasonal (winter only) grazing where possible (Somers et al. 2000).
Provide native vegetation buffers around wetlands to filter pollutants and benefit wildlife (Somers et al. 2000).

Management Practices

Conservation Programs and Partnerships

Description

Mountain and Piedmont bogs are among the rarest natural communities in the Southern Appalachians and in North Carolina. Unlike northern bogs of glacial origin, Southern Appalachian bogs form in poorly drained depressions or on gentle slopes, generally in relatively flat valley bottoms which are not subject to flooding. They may vary from being permanently wet to intermittently dry and are generally fed by seepage. They are underlain by wet organic or mucky mineral soils, which are very acidic.

The factors responsible for creating and maintaining bog communities are not well known. Grazing has been nearly universal in bogs, and few examples exist in pristine condition. Most are experiencing invasion of shrubs or trees at the expense of the herbaceous zones. This tendency toward rapid succession suggests that some form of periodic or chronic natural disturbance, now disrupted, may have kept the bogs open. Potential past disturbances include flooding by Beavers, grazing by herds of large mammals, fires, and clearing by Native Americans.

There are three community types within this ecosystem: Southern Appalachian bog, Southern Appalachian fen, and swamp forest–bog complex:

The Southern Appalachian bog and Southern Appalachian fen types have a mosaic or zoned pattern of shrub thickets and herb-dominated areas, mostly underlain by sphagnum mats. Trees may be scattered throughout or may dominate on the edges. The shrub and herb layers of the bog, while not highly diverse, are uniquely adapted to the acidic, nutrient-poor environment of the bog and may include numerous rare species. Fens occur on high pH (basic) soils, but otherwise have the same vegetative zones as bogs; only one Southern Appalachian fen is known in North Carolina (in Ashe County).
Swamp forest-bog complex types occur along streams and are dominated by trees, but may have boggy herbs and sphagnum moss in canopy openings.

The 2005 WAP described bogs and associated wetlands (mountain bogs) as a priority habitat in the Southern Blue Ridge Mountains ecoregion (see Chapter 5) (NCWRC 2005).

Location of Habitat

Mountain bogs (including fens and ‘wet meadow’ bogs) are distributed throughout the Mountains and upper Piedmont of North Carolina, with examples as far east as Forsyth and Gaston Counties. Most of the known occurrences of Southern Appalachian bogs and fens are situated above the Blue Ridge escarpment, in the northwestern (Ashe and Alleghany) and southern (Henderson, Transylvania) counties. On the other hand, ‘wet meadow’ bogs can be found in the western half of the Piedmont and throughout the Mountain counties. Over 60% of the wetlands identified in the Southern AppalachianAssessment (SAMAB 1996 in NCWRC 2005) occurred on privately owned lands and it is likely that overall, the percent of mountain bog habitat in private ownership is even greater.

Problems Affecting Habitats

Invasive Species

Invasive species are already a problem in some areas and may increase with drought and warmer temperatures. Some bogs are subject to invasion by exotic plants such as Japanese Stiltgrass, Multiflora Rose, and Asian Dayflower. Many of these communities contain pines, hemlocks, or spruces, which are susceptible to insect pests.

Drought and warm temperatures may allow generalists and upland species to invade. Many of the rare species associated with mountain bogs and fens are herbs and are vulnerable to competition from woody species and more aggressive habitat generalists. If changes in hydrology make these sites drier, this problem is likely to be exacerbated.

Climate Impacts. Besides stream flooding, overland runoff from adjacent uplands during severe storms would be a problem in many bogs. The nutrient input and potential scouring of severe floods would be detrimental to bog communities. Droughts would have significant effects on competitive relationships among species and on the community as a whole. Many bogs may reduce in size if margins dry out due to drought. Some estimates indicate that fewer than 500 acres of mountain bogs in North Carolina remain (USFWS 2002).

Fragmentation

The most common types of fragmentation occur when streams are impounded to form lakes, highways are built across inhabited wetlands, and wetland habitat units are drained for agricultural use or development. Roads that bisect Bog Turtle wetlands are the single most detrimental threat to turtle populations. Highway mortality is high in areas where turtles must cross roads to get from one wetland to another (Somers et al. 2000).

Successional Conversion

Bog communities can undergo ecological succession, from open canopy fens and bogs to closed canopy swamps (where hydrologic conditions do not change), leading to the loss of habitat suitable for Bog Turtles and other species dependent on these types of wetlands (Klemens 1993; Herman and Tryon 1997; Rosenbaum et al. 2007).

Climate Change Compared to Other Threats

Comparing climate change to other ecosystem threats can help define shortand long-term conservation actions and recommendations. While climate change is not the most severe threat, a combination of synergistic effects with other existing conditions could stress these systems to the point where several species are unable to persist.

Climate change effects such as droughts and severe flooding may be particularly problematic in these communities. Climate change, however, is not likely to be as detrimental compared to impacts caused by a number of immediate threats that can cause more drastic destruction than climate change is likely to. The largest scale problem affecting mountain bogs and wetlands in general has been and continues to be the conversion of these habitats to other land uses. Table 4.15 summarizes the comparison of climate change with other existing threats.

quoted from the 2015 North Carolina Wildlife Action Plan

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