The Okaloosa darter (Etheostoma okaloosae) is a small, elongate, slightly compressed
darter, with adults ranging in size from 27-49 millimeters
standard length. Its preferred habitat is in the margins
of clear flowing streams among the vegetation and woody
debris. The darter’s diet consists mostly of immature
aquatic insect larvae, primarily midges, mayflies and caddisflies.
It is only found in six stream systems located in the lower
portions of Okaloosa and Walton counties in northwest Florida.
Its entire range totals only 242.8 stream miles.
The Okaloosa darter was added to the endangered species
list in 1973 due to its small range and the suspected severe
impacts to the population as a result of historical land
use practices which caused a decline to as little as 1,500
individuals. Threats to the population such as artificial
impoundments and habitat degradation caused by erosion and
siltation are among the most important reasons for its endangered
status. More than 98.7% of the habitat occupied by the darter
is located on Eglin Air Force Base (Eglin) in northwest
Florida. Eglin Air Force Base environmental managers along
with the U.S. Fish and Wildlife Service have been at work
to reduce land use impacts and rehab the impaired streams
for more than 15 years. The remaining darter habitat is
in the surrounding developed areas of Niceville and Valparaiso
where management, habitat preservation and habitat improvement
has historically been more difficult.
Through the habitat improvement efforts and population monitoring
of the darter by Eglin’s natural resource managers
along with the Service and its partners at Loyola University
and the U.S. Geological Survey in Gainesville, FL, the population
of darters on Eglin has improved dramatically in the recent
past. The Service has made great strides in achieving recovery
actions detailed in the recovery plan (1981) which led to
the recommendation for downlisting the darter from endangered
to threatened status in 2010. There are still recovery actions
that have to be met in order to remove the species from
the endangered species list, however, this is a great achievement
for the managers working to protect the Okaloosa darter.
Quick darter facts:
• Listed as ENDANGERED in 1973 (population 1,500)
• Only exists in six creeks in Northwest Florida (see
map)
• Lives along margins of clear-flowing streams in
vegetation and woody debris
• Two to four year lifespan
• Spawns in vegetation (Mar. - Oct.)
• Size: three inches long
• 98.7 percent of darter habitat is found on Eglin Air
Force Base
• Stream restoration projects have significantly improved
darter habitat within Eglin’s boundaries
• Downlisted to THREATENED with an estimated population of more than 600,000 in 2010
Additional Information
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