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significance could, indeed, be measured, then it may be practical to develop <br />numerical objectives for whooping crane stopovers on the central Platte River. <br />After the September 2000 workshop, Dr. Jim Lewis provided Dr. Doug <br />Johnson, statistician at the USGS, Northern Prairie Wildlife Research Center, <br />Jamestown, North Dakota, with information regarding this issue and requested <br />his analysis of existing whooping crane data. Dr. Johnson concluded that the <br />existing data suggests that the recent (since 1985) increase in whooping crane <br />sightings on the Platte River is only partly due to a larger population and that <br />some of the increase may be due to either greater detectability of birds using <br />the Platte River or increased use of the area. 65 His analysis suggested that <br />managers should be able to detect a doubling of the number of sightings on the <br />Platte River. In addition to Dr. Johnson's analysis, several scientists at the <br />USGS's Midcontinent Ecological Science Center (MESC) in Ft. Collins, <br />Colorado, reviewed Dr. Johnson's analysis and agreed with his conclusions. <br />The MESC has been involved with Platte River whooping crane roosting <br />modeling techniques and other Platte River studies for many years. <br />Based on Dr. Johnson's analysis, it was concluded that managers should be <br />able to detect increased whooping crane use of the Platte River due to factors <br />other than just an overall increase in the AWP (e.g., response to habitat <br />improvements). Therefore, the question regarding the ability to statistically <br />detect a doubling of whooping crane use on the Platte River should be <br />discounted as an obstacle in developing whooping crane use objectives and <br />monitoring protocols. <br />Dr. Johnson's analysis was completed based on information provided by Dr. <br />Lewis. The data was split at 1985, the time when habitat management for <br />whooping cranes first began along the Platte River.66 67 In addition, the <br />analysis was done based on the number of cranes seen, not the number of <br />sightings. Each sighting sometimes includes more than one crane. The <br />analysis of numbers of birds was chosen because of the noted trend for greater <br />numbers of birds seen per sighting as the AWP has increased. This report, <br />however, recommends that a more detailed statistical analysis be completed of <br />65 Douglas H. Johnson, U.S. Geological Survey, Jamestown, North Dakota. E-mail <br />correspondence to Jim Lewis, Statistical Analysis. December 1, 2000. <br />66 Strom, K. 1987. Lillian Annette Rowe Sanctuary -- Managing Migratory Crane <br />Habitat on the Platte River, Nebraska. Pages 326 -330 in Proceedings 1985 Crane <br />Workshop, Platte River Whooping Crane Habitat Maintenance Trust and U.S. Fish and <br />Wildlife Service. 415 pp. <br />67 Lingle, G.R. 1982. Mormon Island Crane Meadows -- Protecting Habitat for Cranes <br />along the Platte River, Nebraska. Pages 17 -21 in Proceedings 1981 Crane Workshop, <br />National Audubon Society, Tavernier, Florida. 296pp. <br />24 <br />