During 1995 and 1998, a total of 110 site surveys for amphibians and reptiles were conducted by Montana Natural Heritage Program biologists in the Bureau of Land Management Miles City District (the former Billings, Big Dry, and Powder River Resource Areas) in eastern Montana. During the 1998 contract period, 102 site surveys were conducted (8 of these were nocturnal roadside call surveys, 94 were standard surveys) during April to July. All surveys were conducted by one individual. Surveys took from 5 to 180 minutes (mean = 58.5 min) and consisted of a thorough search of the wetland perimeter in combination with netting of near shore aquatic habitats for adults, eggs, larvae, and tadpoles. Sampling was done by hand and dipnet. At seeps, rocks and logs were overturned in and near wet areas to expose hidden individuals. In addition to site surveys, observations of road kills were recorded, as were fortuitous sightings by those conducting the surveys or other reliable individuals. Ten species (6 amphibian and 4 reptile) were detected within the Miles City District area during 1998 site surveys. Species included: Tiger Salamander (Ambystoma tigrinum), Woodhouse's Toad (Bufo woodhouseii), Great Plains Toad (Bufo cognatus), Western Chorus Frog (Pseudacris triseritata), Plains Spadefoot (Spea bombifrons), Northern Leopard Frog (Rana pipiens), Painted Turtle (Chrysemsy picta), Racer (Coluber constrictor), Plains Garter Snake (Thamnophis radix), and Common Garter Snake (Thamnophis sirtalis). Four reptile species encountered in 1998 other than on site surveys include Smooth Green Snake (Liochlorophis vernalis), Gopher Snake (Pituophis catenifer), Western Hognose Snake (Heterodon nasicus) and Western Rattlesnake (Crotalus viridis). In addition, Short-horned Lizard (Phrynosoma hernandezi), Sagebrush Lizard (Sceloporus graciousus) and Western Terrestrial Garter Snake (Thamnophis elegans) were reported from the Miles City District by other observers in 1998. In 1995, 3 species were detected during 8 site surveys in Carbon County: Tiger Salamander, Western Chorus Frog, and Plains Spadefoot. Short-horned Lizard, Sagebrush Lizard, Gopher Snake, and Western Rattlesnake were also encountered, but not during surveys. Of the 1998 surveys, 95.1% had one or more amphibian or reptile species present. Western Chorus Frog, Northern Leopard Frog, and Plains Garter Snake were the most frequently encountered species in 1998, being recorded on 67.6%, 61.7% and 22.3% respectively, of the site surveys. Species with records from the Miles City District area, but not encountered during the 1995 and 1998 surveys, include Bullfrog (Rana catesbeiana), Common Snapping Turtle (Chelydra serpentina), Spiny Softshell (Trionys spiniferus), and Milk Snake (Lampropeltis triangulum). Western Toad (Bufo boreas), Columbia Spotted Frog (Rana luteiventris), and Rubber Boa (Charina bottae), all with montane affinities, have been documented but are marginal to the Miles City District in the west. The Canadian Toad (Bufo hemiophrys), although recorded from the Miles City District area in 1966, is now considered historical (not reported in >30 years). Wood Frog (Rana sylvatica) might be documented eventually from the Miles City District area in the Big Horn Mountains of Big Horn County.