Survey Finds State DOTs Feel Biodiversity Is a New Issue in Transportation
In 1995, the Transportation Research Board's Task Force on Natural Resources
(A1F52) conducted a national survey of state transportation agencies. The
survey's intent was to determine if and how the agencies addressed biodiversity in
their projects. In their article "Current State of Biodiversity Impact Analysis in
State Transportation Agencies" (Transportation Research Record 1559), Robert
L. Herbstritt and Anne D. Marble discussed the results of the survey. Because
transportation projects can significantly affect biodiversity, it is likely
transportation agencies will become increasingly involved in analyzing that
impact. To date, however, transportation agencies receiving federal funds are not
required to analyze their projects' impact on biodiversity.
In their report, the authors gave a definition of biodiversity from a recent book by
Edward O. Wilson, a biologist in the field of biodiversity. Wilson's book defined
The variety of organisms considered at all levels, from genetic variants
belonging to the same species through arrays of genera, families, and still
higher taxonomic levels; includes the variety of ecosystems, which
comprise both the communities of organisms within particular habitats and
the physical conditions under which they live.
Editor's note: It might be helpful to share two less complex definitions of biodiversity that
we found in on-line reference sources. The Merriam Webster "Britannica Online" defines
biodiversity as "biological diversity in an environment as indicated by numbers of different
species of plants and animals." The on-line "BioTech Life Sciences Dictionary" from
BioTech Resources describes biodiversity as "[t]he existence of a wide range of different
types of organisms in a given place at a given time."
The survey asked each state department of transportation (DOT) the following
- Has the biodiversity issue been raised in the highway development
- If so, how has the subject arisen?
- Which agencies have requested information?
- What type of information has been requested and for which projects?
- What was the DOT response?
- Is it your understanding that biodiversity is becoming a new issue?
- Have you completed any biodiversity studies?
- Were significant impacts identified? Was the information used to make
Thirty-two state DOTs responded to the survey. Twenty-one (66 percent) replied
that the issue of biodiversity had been raised during the highway development
process. Eleven of the 32 (34 percent) said that to date biodiversity had not been
an issue in their transportation development process. Of the 21 state DOTs that
said the issue of biodiversity had been raised, only Louisiana, Pennsylvania,
Virginia, and West Virginia indicated they had completed or were completing
studies specifically dealing with biodiversity. Arkansas, Illinois, and Minnesota
"reported being involved in corridor acquisition or enhancement programs dealing
mainly with the enhancement and maintenance of prairie grass corridors in the
Midwest." Thirteen states said that while they had not been involved in any
large-scale studies, "they have been asked to consider impacts on biodiversity in
a qualitative manner in relation to connectivity of habitats, effects of habitat
fragmentation, secondary impacts, and cumulative impacts."
Many states indicated the U.S. Fish and Wildlife Service (FWS) was the
government agency that most often asked for information concerning biodiversity.
Among other agencies requesting information were the Environmental Protection
Agency (EPA) and the U.S. Army Corps of Engineers (ACOE).
The biodiversity issues revealed by the survey were in three categories, though it
should be noted "these categories are significantly interrelated, particularly
Categories 2 and 3."
Category 1: Protecting Unique, Rare, or Sensitive Habitats/Species
While such action is not a pure method of biodiversity protection, it is nonetheless
a "significant component." This type of protection frequently involves a regulation
with which DOTs must comply; consequently, "all of the DOTs practice this type of
biodiversity protection. However, if this is the only strategy employed, it often
results in a piecemeal approach that responds only to crisis situations when
species or unique habitats have become extremely rare and endangered." Maine,
California, Virginia, and Florida were among the states that had addressed this
Category 2: Minimizing Fragmentation and Promoting Connectivity of
Strategies designed to address this issue included forest patch analysis and
connectivity studies. Several DOTs had employed Category 2 strategies,
including Pennsylvania, West Virginia, Kansas, Texas, and Louisiana.
Category 3: Managing Watersheds and Ecosystems
Arizona, Colorado, and Montana replied "that they are beginning to take a larger
ecosystem approach to the issue of biodiversity." Like Arizona, the DOTs in
Idaho, Pennsylvania, and Utah "have developed state-specific programs of
biodiversity using the gap analysis method." This method "is beneficial because it
identifies gaps in the representation of biodiversity and can be used to evaluate
large regional areas." However, these states have not incorporated gap analysis
in projects related to transportation.
There was no apparent consensus among the DOTs on the exact meaning of the
term biodiversity, nor on the most effective methods to measure or evaluate
impacts on biodiversity. Also, most of the states had not conducted studies
designed to measure those impacts. However, the majority agreed "biodiversity is
becoming a new issue in the transportation development process."
Copyright © 1997 by TranSafety, Inc.
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