MACRO INVERTEBRATE COLLECTION OF SELECT STREAMS ON THE FORT BERTHOLD INDIAN RESERVATION

1. MACRO INVERTEBRATE COLLECTION OF SELECT STREAMS ON THE FORT BERTHOLD INDIAN RESERVATION Tanya Driver Fort Berthold Community College PO Box 490 New Town, ND 58763

2. INTRODUCTION • Prairie streams in the Great Plains have received little attention in terms of their ecology. The use of biological and habitat surveys is becoming the standard for assessing the the status of aquatic ecosystems. Analysis of macro invertebrates is a common method of assessing water quality and biological health of streams.

3. ADVANTAGES OF USING MACROINVERTEBRATES • Limited migration patterns. • Assemblages are made up of species that constitute a broad range of feeding strategies and pollution tolerances. • Primary food source for fish, their health and abundance has a positive effect on fish populations. • Macro invertebrates are abundant in most streams and have the potential for high diversity in unimpaired waters.

4. LOCATION DESCRIPTION • The Fort Berthold Reservation covers an area of 1530 square miles. The west side of the reservation is primarily rangeland. Agriculture is the dominant use on the eastern portion of the reservation

5. METHODS • EMAP methods developed by the EPA. EMAP studies involve random selection of study sites. The of the random sampling scheme is to allow investigators to maker inferences regarding the general status of streams in a geographic area.

6. METHODS • Macroinvertebrate samples were collected using a D-frame net with a 500 um mesh. One square foot of substrate was sampled at each transect line. Samples from each transect were pooled , sieved to remove rocks and debris and preserved in 100% ethanol.

7. TRANSECTS • Measured stream width at five locations to determine an average width. • Established a study reach with a length that equaled 40 times the average channel width. • Measured the reach with a tape measure, places flags labeled A-J at every 1/10th the reach length. • Transects established perpendicular to the stream channel direction at the sampling point location

8. OBJECTIVE • The objective of this study was to compare two streams from each side of the reservation. This was for comparison of the macro invertebrate populations and what impact land use had on the streams. We established three sampling sites per stream, upstream and downstream

9. MEASURES • Richness measures of pollution-tolerant and intolerant taxa are commonly used in bioassessment criteria for streams. • No intolerant taxa were sampled at these streams. • Tolerant taxa were relatively abundant at all sites.

10. DEEPWATER CREEK • 1A-Analyses provide a significant amount of information on the status of this site. Showed evidence of nutrient enrichment and species adapted to little or no flow. • 1B-Supported an abundance of perlid stoneflies, and overall diversity of invertebrates. • 1C-Populations show indications of moderate impairment. Could be related to beaver dams or agricultural chemicals.

11. BEAR DEN CREEK • 3A-High proportions of EPT taxa and low proportions of noninsect taxa. Evidence of nutrient enrichment. • 3B-Had excellent habitat conditions. • 3C-Indications of good biological integrity and good diversity. Elevated Hilsenhoff biotic index suggests nutrient enrichment.