Application to subregional planning
The biogeography research task will provide mapping of physical features, land
uses, and vegetation to portray the options for the design of a subregional reserve
and corridor network. The other research tasks will assist planners in evaluating
conservation planning options by documenting species distributions and relative
abundances within each subregion, by identifying the sizes and configurations of
habitat patches necessary to sustain stable demographic units of target species,
and by assessing the physical characteristics of landscape corridor linkages
required to facilitate dispersal, gene flow, and recolonization by species inhabiting
the coastal sage scrub community.
Based on this information, subregional NCCPs will designate a system of
interconnected reserves designed to: 1) promote biodiversity, 2) provide for high
likelihoods for persistence of target species in the subregion, and 3) provide for no
net loss of habitat value from the present, taking into account management and
enhancement. No net loss of habitat value means no net reduction in the ability of
the subregion to maintain viable populations of target species over the long-term.
The NCCP will need to establish a wide range of habitat management and
enhancement tools and incorporate a monitoring program to provide guidance for
ongoing management. With improved techniques for management and restoration,
the goal of no net loss of habitat value may be attainable even if there is a net loss
of habitat acreage.
Several basic tenets of reserve design should be applied to each subregion:
- Conserve target species throughout the planning area: Species that are well-distributed across their native ranges are less susceptible to extinction than are
species confined to small portions of their ranges.
- Larger reserves are better: Large blocks of habitat containing large populations of
the target species are superior to small blocks of habitat containing small
populations.
- Keep reserve areas close: Blocks of habitat that are close to one another are
better than blocks of habitat far apart.
- Keep habitat contiguous: Habitat that occurs in less fragmented, contiguous
blocks is preferable to habitat that is fragmented or isolated by urban lands.
- Link reserves with corridors: Interconnected blocks of habitat serve conservation
purposes better than do isolated blocks of habitat. Corridors or linkages function
better when the habitat within them resembles habitat that is preferred by target
species.
- Reserves should be diverse: Blocks of habitat should contain a diverse
representation of physical and environmental conditions.
- Protect reserves from encroachment: Blocks of habitat that are roadless or
otherwise inaccessible to human disturbance serve to better conserve target
species than do accessible habitat blocks.
Table of Contents |
NCCP Home |
DFG Home