Selection
Criteria for (SuAsCo) Biodiversity Protection Sites
The
criteria for selecting Biodiversity Sites are based upon current
conservation biology science. These parameters are derived from
several publications, white papers, and interviews with scientists
and local authorities.
Sites have been selected for biodiversity values only. Aesthetics,
agricultural values, recreational use, and water supply protection
were not considered, although in many cases Biodiversity Sites
may contribute to them. In some cases, these other values are
in conflict with biodiversity values. These issues will be addressed
in the section on stewardship. Threats or feasibility of protection
were not considered in the selection criteria. The intent of
the list of SuAsCo Biodiversity Sites is to indicate what are
the important sites for biodiversity and why, so that leaders
and concerned citizens can make a clear choice as to their goals
and then determine how to proceed.
Overarching
Priorities:
Areas on the Natural Heritage & Endangered Species
(NHESP) BioMap
Areas
of Critical Environmental Concern (ACECs)
-
Large parcels with a mosaic of quality habitats, both upland
and wetland
-
Large patches of quality community types (Ex. Red maple swamp,
forest)
-
Small patches of quality, unusual community types which are
well buffered. (Ex: kettlehole bog, rock outcrop)
Evaluation
Guidelines:
Size
and configuration:
Large parcels, preferably with a core of protected conservation
land. Large, more or less circular, unfragmented parcels have
less edge and more interior area to natural communities. Large
areas tend to include more diversity with a matrix community type
and often include other small patch communities. While forest
parcels of over 1000 acres are preferable and feasible within
the SuAsCo Watershed, adequate size varies according to community
type of Focal Species
Areas
shown on MNHESP Atlas:
Priority Habitat for Rare Species and Estimated Habitats for Rare
Wildlife and Certified Vernal Pools; also exemplary natural community
types. The inclusion of these sites in the SuAsCo Biodiversity
Sites was based on the quality of the occurrence as recorded by
Natural Heritage and the context of the site. All the coverages
indicated by the NHESP Atlas should be given special consideration.
Connectivity:
Sites that are adjacent to other protected sites enhance the values
of both. Connections to resources beyond the watershed boundary,
as well as within the watershed, are important.
Buffers/perimeters: Low density development, relatively small
roads, and similar adjacent habitat protect and enhance the value
of the core site.
Representation of different natural communities:
Protection of good examples of different community types listed
by the NHESP in their publication Natural Communities of Massachusetts.
By representing different community types, the range of organisms
from invisible mites to site specific birds will be protected.
Viable populations or regular occurrences of Focal Species:
Sites that are likely to or in fact do support viable populations
of Focal Species or sites that regularly support healthy individuals
of Focal Species so that these individuals contribute to viable
populations (see list of Focal Species below).
Linkages/corridors: Linkages along wetlands and streams or vegetated
wildlife corridors that can be protected and managed for wildlife.
Natural disturbance dynamics:
Areas where natural dynamics of forest succession, flooding, and
beaver activity are able to continue without undo interference
by people.
Minimal
exotic species:
Areas with minimal invasion of invasive exotic species or where
exotics are manageable with readily available resources.
Good examples or unusual combination of geological features: Intact
drumlins, eskers, glacial moraines, kame terraces, or riverine
bluffs feature different soil types, topography, and hydrology
that contribute to formation of different natural communities.
Topographic variability: Topographic variability has been shown
to increase native biodiversity.
Human disturbance:
In general, sites with less human disturbance are better than
disturbed sites. The latter include invasions by exotic species,
recent forest cuttings, hydrological alterations (including ditching,
damming, filling, discharges, and water withdrawals), topographical
changes (grading or excavation), soil disturbances, etc. There
are exceptions to this criterion. Grasslands, successional fields,
and wildlife management areas, such as Great Meadows impoundments,
provide habitat for certain Focal Species. In some cases reservoirs,
utility corridors, and aqueducts may be important. It is understood
that virtually all our landscape has been influenced by human
activity in the past to some degree or another.
Permanently protected conservation land:
Already protected lands owned and managed by federal and state
agencies, municipalities, or non-profit organizations with a conservation
mandate are particularly good core areas.
Defensible from detrimental disturbance:
Areas that are defensible from encroachments or detrimental disturbance
in the future, such as lands with conservation restrictions (CRs),
agricultural preservation restrictions (APRs), or public water
supplies.
Organizational capacity: Areas where management of habitats, including
restoration, can be done with minimal inputs over the long-term
and the ownership entity has the mandate and/or capacity to manage
for natural biodiversity.
Distribution:
When possible, community types should be represented throughout
the watershed to provide biodiversity reserves in different locations
and to reduce risk of loss by localized stochastic events, such
as disease outbreaks, windstorms, and fire.
(from
SuAsCo Biodiversity Plan 2000 – Section III 1-3) |
Biodiversity Days 2005