In the 1999 darter study, 7 riffles were collected using the strip removal technique. In the strip transects, 399 specimen representing 15 fish species were identified. Of the almost 400 fish identified, the one taken most frequently was the spotted darter with some 118 identified in the strip removals. Banded darters and banded sculpin were taken in about the same numbers (74 and 86 respectively). Of the remaining species, stonerollers were fairly common, and greenside darters were taken frequently. All remaining species were taken sporadically at the various sites. No fantail darters were collected in any of the riffles. Interestingly, for the first time, a large number of variegate darters (13) were taken at the Rothrocks Mill site.
The numbers of fish taken were summarized and compared with collections taken in previous years (Table 1). These data indicate that the numbers of banded darters and bluebreast darters taken in the riffle samples have decreased while the numbers of spotted darters has decreased only slightly since 1995.
Table 2 lists the collection sites during the various studies performed on the darter populations of The Blue River.
In 1999, the estimated total number of fish per 100 square feet of riffle area was 28.84. This included an estimated 3.51 banded darters per 100 square feet, 8.97 spotted darters per 100 square feet and 0.91 bluebreast darters per 100 square feet.
In 1995, 210 fish were collected from seven riffles. This was calculated to be 26.5 estimated fish per 100 square feet of riffle area. Of these banded darters were estimated to be at 5.93 fish per 100 square feet, 9.79 spotted darters per 100 square feet and 1.08 bluebreast darters per 100 square feet.
In 1986, nine riffles were collected at four downstream locationsresulting in an estimated 37.55 fish per 100 square feet of riffle. Banded darters were at 7.77 per 100 square feet, spotted darters were at 3.11 per 100 square feet and bluebreast darters were at 5.77 per 100 square feet.
This analysis was then broken down into a site ana;ysis of all fish taken. Then a population analysis with 95% confidence intervals of the numbers of spotted, banded, bluebreast and variegate darters taken at each site was performed. The population varies considerably from 3.25 fish per 100 square feet at Stage-Stop Campgroung to a very high 53 fish per 100 square feet at Rothrock's Mill.
Spotted darter populartion estimates were highest at Harrison Springs (24.1) and Rothrock's Mill (22.9) and lowest at Stage-Stop Campgraound (1.16). Bluebreast darters were most common at Rothrock's Mill (3.33), but this number is a sharp decrease from the number taken in 1986 when 11 per 100 square feet were collected. The numbers of spotted darters ranged from none collected at White Cloud to 13.75 at Rothrock's Mill.