Northern Prairie Wildlife Research Center
Status of the Arkansas Darter in South-central
Kansas and Adjacent Oklahoma
Results
The Arkansas darter was recorded from 67 (46%) of the 145 localities sampled
from 1994 through 1997 (Fig. 2). Included among
these samples, scattered throughout the study area, were 39 stream segments
where Arkansas darters had been reported prior to 1994. The Arkansas darter
was captured at 26 (67%) of these 39 historic localities. The other 41 (28%)
of the 145 sample localities where the Arkansas darter was collected were previously
unreported collection sites located within the general historic range of this
species. Thirty-seven (25%) of the 145 sites were located outside of the general
southern boundary of the historic range of the Arkansas darter (Fig.
2). If we excluded these 37 sample localities outside of its known area
of distribution, the Arkansas darter was present at 62% of the sample sites
(67 of 108 sites) generally within its historic range. Of the 67 sites where
the Arkansas darter was captured, its numbers exceeded 50 individuals at 16
sites (24%). Range contraction due to habitat loss has occurred in the western
portion of the study area, generally west of Crooked Creek.
At sites where the Arkansas darter was captured, water temperature varied
from 17.0 to 29.3°C. Specific conductance was between 355 and 2700 µS/cm.
Canopy cover varied from 0 to 100%, but most localities, including those where
the Arkansas darter was absent, had canopy cover estimates of less than 10%.
Stream substrates consisted of sand, silt, and organic muck. Submerged, floating-leaved,
and emergent macrophytes present at collection sites included Ceratophyllum,
Lemna, Myriophyllum, Nasturtium, Potamogeton, Sagittaria, and Scirpus.
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