![](http://www.alamy.com/thumbs/6/AEC77CF1-92E7-45D5-818B-6FB8BE97231B/RG6YYK.jpg)
. Bull Mountains coal field study : progress report, 1976 : research conducted by Montana Department of Fish and Game, Environment and Information Division and Consolidation Coal Company. Wildlife management; Animal ecology; Coal mines and mining. ' ' '• ;'.- The annual increment, calculated from fall observations, was 27 percent. Production data during this report period were similar to that of the past 2 years (Dusek and McCann 1974 and 1975). Various observability bias' precluded an estimate of a total elk population by direct count. An estimate of the cow segment (yearlings and older) was
. Bull Mountains coal field study : progress report, 1976 : research conducted by Montana Department of Fish and Game, Environment and Information Division and Consolidation Coal Company. Wildlife management; Animal ecology; Coal mines and mining. ' ' '• ;'.- The annual increment, calculated from fall observations, was 27 percent. Production data during this report period were similar to that of the past 2 years (Dusek and McCann 1974 and 1975). Various observability bias' precluded an estimate of a total elk population by direct count. An estimate of the cow segment (yearlings and older) was computed from ratios of marked to unmarked cows. This was accomplished by use of a modified Lincoln Index (Martinka 1969) as fol1ows: PE = M/PM where PE is the estimated cow population, M is the number of marked cows present, and PM is the percent of the cows that were marked. A total population was estimated from this, as well as summer calf:cow and "spike":cow ratios and fall older bull:cow ratio. All seven marked cows were observed during the summer-fall period during 1975. The estimated cow segment was 67 animals. From this the estimated numbers of calves, "spike" bulls, and older bulls were 36, 13 and 14, respectively. Thus, the estimated population of elk in the Bull Mountains during the summer-fall period of 1975 was 130 animals. -35-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Dusek, Gary L; Montana. Department of Fish and Game. Environment and Information Division; Consolidation Coal Company. [S. l. : s. n. ]
Size: 2297px × 1088px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookpublisherslsn, booksubjectcoalminesandminin