to form deep pools with more frequent riffle areas. Steep, eroded banks 

 line the lower reach, resulting in an extremely silt-laden substrate. 

 The change in elevation from source to mouth was 324.0 m (Figure 4). 

 Habitat conditions of the tributaries were similar to those noted for 

 Beaver Creek. Substrate of most study streams was muddy. 



A total of 24 intensive sampling stations were established on Beaver 

 Creek. The number corresponding to the number of the section that the 

 creek flowed through was assigned to the station. Physical parameters 

 were measured, aquatic invertebrates and fish ponulations were sampled at 

 each site. Specific locations for each section are shown in Appendix I. 

 Each named tributary was given an alphabetical designation and sampled as 

 follows: Little Beaver Creek (LB), 3 sections; Hay Creek (H), 2 sections; 

 Lame Steer Creek (L), 2 sections; Smith Creek (S), 3 sections; Box Elder 

 Creek (BE), 5 sections; Cotton Creek (C), 1 section; Glendive Creek (IG), 

 2 sections; Griffith Creek (G), 1 section; Krug Creek (K), 2 sections; 

 and Hodges Creek (W), 1 section. Specific locations for each sampling 

 section are presented in Appendix II. 



METHODS 



A visual survey was conducted on all tributaries to Beaver Creek and 

 all west flowing tributaries to the Yellowstone River between Glendive 

 Creek and Smith Creek. Streams which did not contain a steady flow v/ere 

 eliminated from the study. These streams are shown on Figures 2 and 3 as 

 broken lines. Base maps (BLM Surface Management Quads, 1:126,720; USGS 

 topographic quads, 1:24,000) and rectified aerial photos (1:24,000) were 

 used to identify possible study reaches. Each section through which each 

 creek flowed was consecutively numbered starting at the mouth. Study 

 sites were selected for each stream based on habitat conditions (inclusion 

 of variety of habitat types) and access. 



Physical parameters were measured at each study section according 

 to stream survey methods outlined in BLM Manual 6671. Field data were 

 recorded on stream habitat survey field form number 6671-1. Water 

 temperatures were recorded at two sections in 1977 (Sections 54 and 84) with 

 Partlow 31 Day Recording Thermographs and at three sections in 1978 (Sections 

 1, 54 and 84) with Taylor 31-Day Recording Thermographs (Figure 2). 

 Temperatures were recorded in °F and converted to OC. Limited chemical 

 analyses were run using a Hach DR-EL 2 and Hach Model AL-36-P. Conductivity 

 and dissolved oxygen were recorded using a YSI model S-C-T meter and a 

 YSI Model 57 oxygen meter, respectively. 



Aquatic invertebrates were sampled by a variety of methods. Initial 

 plans for quantitative sampling were abandoned early in the study when 

 it became evident that most sites did not have adequate flowing water for 

 use of either Water's Round or Surber samplers. Organic debris and 

 rocks eliminated the use of a dredge at most sites. Most samples were 

 modified kick samples, and many were taken by digging up the stream bottom 

 with a dip net. A few Water's Round samples were collected. Adult Odonata 

 were collected with an adult net and/or by shooting with a .22 birdshot. 



