Final Report of the New Jersey State Comparative Risk Project
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Habitat loss is the conversion of land from one use to another, specifically the development
of wild or agricultural lands to urban and suburban land uses. Habitat loss also includes the
conversion of natural habitat to agriculture, the conversion of dunes to seawalls, and the
modification of wetlands by dams and channelization. Habitat degradation is the leading
cause of endangerment for all groups of organisms in the mainland Unites States, ranking
ahead of exotic species, pollution, over-exploitation, and disease. In New Jersey, these
changes affect thousands of acres per year, resulting in the reduction of available habitat
for native plant and animal species and decreasing the resilience of ecosystems to accom-
modate other natural and human caused stressors.
What’s at risk?
Habitat loss affects all terrestrial and aquatic plant
and animal populations and ecosystems state-
wide, especially those found on undeveloped,
unprotected land. Unprotected forests and
wetlands are particularly at risk. Regions that still
contain large tracts of critical wildlife habitat are
especially vulnerable to the effects of habitat loss.
These include the Pinelands region (1.1 million
acres) and the New Jersey Highlands (640,000
acres). Socioeconomic impacts of habitat loss
are included among the impacts discussed under
Land Use Change.
What are the ecological impacts in New
Jersey?
Most of the plants and animals listed as endan-
gered or threatened in New Jersey are imperiled
due to habitat loss. Endangered tree frogs native
to the Pinelands are being displaced by more
disturbance-tolerant bullfrogs. Pinelands plant
communities have also been altered as native
species are replaced by invasive exotics in more
developed areas. Bird species diversity is also
known to decrease as the proportion of urban
land increases. New Jersey has lost 40% of its
wetlands and 35% of the Pine Barrens since pre-
settlement times, and has 50% less farmland than
in 1950. Naturally vegetated shoreline areas
provide habitat and perform critical ecosystem
services. Only 29% of Barnegat Bay’s shoreline,
for example, remains undeveloped. Rates of
development continue to increase. During 1984-
1995, 11 of New Jersey’s 21 counties experi-
enced rates of development greater than 20%,
and several grew by more than 30%. Developed
acreage in Salem and Cumberland counties
increased by 50% and 42%, respectively, during
this time. In addition to the direct effects on
species composition, land use change also
compromises ecosystem functions such as
nutrient cycling and water purification and
storage.
What’s being done?
Due to human population pressures, returning
currently developed land to its former state is
not practical on a large scale. Consequently, the
primary management focus should be on pre-
venting further impacts. As of 1998, New Jersey
had 920,000 acres of permanently protected
open space (29% of New Jersey’s total 3.2
million acres). Development is regulated in the
1.1 million acre Pinelands National Reserve, and
most of Barnegat Bay’s remaining salt marshes
and undeveloped shoreline are under some form
of protection.
Habitat loss
Ecological Risk
Human Health Risk
Socioeconomic Risk
H
STRESSOR SUMMARIES
