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The Lakehead Pipe
Line Company (Lakehead) SEP-II project, constructed
in 1997 and 1998, includes ten miles of pipeline right-of-way in Wood and Adams Counties, Wisconsin where the federally endangered Karner
blue butterfly (KBB) is known to occur. Authorization for incidental take of KBBs was granted with US Fish and Wildlife Service Terms
and Conditions intended to restore and enhance disturbed KBB habitat. In
compliance with these conditions, KBB-occupied right-of-way was reseeded with
a combination of native grasses, lupine, and other KBB nectar species in fall
1998. Lakehead is required to monitor the
right-of-way for three years to determine the success of this restoration
effort. Monitoring includes assessment of frequency and density of lupine and
nectar plants, as well as KBB surveys, which consist of a modified
presence/absence survey during the first year and formal counts in the
subsequent two years. First-year monitoring was conducted in July 1999 during
the peak of the KBB second flight. KBBs were
observed at 86% of the sample sites, which was consistent with second-flight
results of pre-construction surveys. Planted nectar species were present on
60-98% of the reseeded property tracts depending on the species, reflecting
good diversity. Frequency within sample plots varied greatly by species,
ranging from zero to 100%. First-year density data reflect the small size of
the seedlings, but seedling coverage was generally good, with some variation
between sites due to soil conditions and amount of disturbance unrelated to
the project. Preliminary results suggest that restoration efforts will, at a
minimum, replace disturbed habitat, and will likely enhance KBB habitat in
the long term.
Keywords: Butterfly, lupine, mitigation, endangered species,
reseed
Ref#: 6-6
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