9574

• UCREFRP Catalog Number: 9574
• Author: Miller, W. J. and D. E. Rees.
• Title: Survey of Fish, Benthic Macrovertebrates, and Habitat in Elkhead Creek near Craig, Colorado.
• USFW Year: 1996.
• USFW - Doc Type: Fort Collins, CO.
• Copyright Material: NO

Elkhead Creek Aquatic Resource Report
Miller Ecological Consultants, December 5, 1996
1

Table 7. Cover types and bank stability at fish sampling sites on Elkhead Creek,
September 1995.
15
Site Habitat Cover Types I (ft'1 L3ulk Stability'
Tv pe
2 3 4 5 Left Right
I Pool 20
Riffle
Glide 30
2 Pool 500
Riffle
Glide
' Cover Types:
' 2 - Instream Cover
3 - Overhead Cover
4 - Combination
5 - Pool Depth
' 2 Bank Stability:
1 - Vegetated and Stable
' 2 - Vegetated and Unstable
3 - Unvegetated and Stable
4 - Unvegetated and Unstable

Macroinvertebrates
5400 1=75%, 2=25% 1=75%,2=25%
1=67%.3=33% 1=33%,3=67%
30 1=80%,4=20% 1=80%a, 4=20%
10500 1=50%,3=50% 3=50%, 4=50%
1=33%,3=67% 1=33%,3=67%
155 3=100% ` 1=33%,3=67%
Macroinvertebrate sampling is becoming a widely accepted tool used to interpret the
biological integrity of aquatic systems. Because of the diversity and documented life
history of aquatic insects, sampling of macroinvertebrates is regarded as a reliable
techniques for describing aquatic conditions (Winner et al. 1980; Clements 1994). To
provide baseline information from the two sites at Elkhead Creek, three replicate samples
were taken from each site. Results of identification, enumeration, and index calculations
are provided in Appendix B. Shannon Weaver Diversity values were 2.96 at Site 1 and
4.11 at Site 2. Evenness values were 0.66 and 0.80 at Sites 1 and 2, respectively. Ward
and Kondratieff (1992) report that Diversity values in Colorado streams generally range
from near 3.0 to 4.0 with values less than 1.0 indicating polluted conditions. Evenness
values are used to detect organic pollution and typically range between 0.6 and 0.8 in
unpolluted streams. The Family Biotic Index is an index used to detect organic pollution.
Values range from 0 to 10 with higher numbers indicating greater stress from pollution.
Number of individuals, number of total taxa, diversity and evenness values were all
greater at Site 2 (Table 8). This data suggests that aquatic conditions at Site 2 are able to
support a larger more diverse and balanced macroinvertebrate community. Functional
feeding group percentages also reflect this trend (Fig 8).