Native Habitat Inventory Final Report 2004 - St. Lucie County

The population of St. Lucie County has increased nearly 400% in 30 years (Table 1).
This has resulted in a loss of native habitat. KBN (1992) reported a loss of 19,267 acres
of natural lands between 1986 and 1991. Between 1992 and 2002 there were an
additional 3,052 acres of natural areas lost. For a total of 22,319 acres lost (22.4%) over
only 16 years. There has been an effort to preserve some of the pieces through
acquisition or conservation easements. This has resulted in 19,417 acres being
conserved. The conservation of additional lands is sought through the Environmentally
Sensitive Lands program. The priority sites described in this report will aid in
determining future potential land acquisitions.
Table 1. Population Demographics for St. Lucie County.
Data from the St. Lucie County Chamber of Commerce web site (Lenze 2002)
Pop.
1970
Percent
Increase
Pop.
1980
Percent
Increase
Pop.
1990
Percent
Increase
Pop.
2000
Percent
Projected
to Increase
2010
Population
Projection
50,836 72% 87,182 72% 150,171 29% 194,100 23% 238,000
The natural communities of these priority sites are described and qualitatively assessed in
the Site Data Summaries and Ranks section. Natural Communities are defined as “a
distinct and reoccurring assemblage of plants, animals, fungi, and microorganisms
naturally associated within each other and their physical environment” (FNAI 1990, p 1).
The physical environment includes soils, water regimes, fire patterns, and topography.
Natural Communities are influenced by human activities such as alteration of flooding
and fire patterns and intensive land management.
The natural resources present within St. Lucie County are the remnants of a much larger
system. The continued persistence of these resources is, in large part, a function of area.
Generally, the number of species in a given area will increase with increasing area
(Mackenzie et al. 1998, p 189). Thus, planning and managing for the long term
persistence of a biological element (e.g., a species or natural community) requires the
knowledge of what is in existence (e.g., inventory) and their minimum biological
requirements.
This report provides some of this information through the site data summaries and GIS
data and analysis. However, even with this information, for nearly all species and natural
communities, there is uncertainty about their minimum biological requirements for longterm
persistence. Thus, long-range planning to protect biological diversity is often done
by making inferences of what is present, or likely present, and using some general
principles (such as the species-area relationship described above) to build a framework on
which to plan sustained existence of these ecological elements. This is the rationale
behind much of the geographic analysis done (i.e., Florida ecological greenways and
Florida Fish and Wildlife Conservation Commission’s strategic habitat conservation
areas) for large-scale ecological planning.
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