Draft Baseline Report - Least Turn and Piping Plover Section

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At the site, a count is made of adult birds and nests. A "nest" is defined to be a scrape with a least one egg. Only birds that are associated with a nesting area are included in site counts; birds seen in the survey region but that are not associated with a nesting area, referred to as `floaters,' are tallied and recorded for each surveyed area, such as bridge segment. The annual census usually consists of airboat surveys through the length of the study area, and ground -based surveys of potential sandpit nesting sites. The timing of airboat survey may be adjusted according to flow and nesting conditions. The survey involves one driver and two spotters checking sandbars for the presence of adult least terns piping plovers and the river in general for bird activity. If adult birds are seen, a thorough survey is made to determine whether the birds are associated with nearby nesting areas. At this time, the breeding census for the central Platte River study area have not been assessed to identify the specific periods or geographic areas of discontinuities. The annual breeding census is relatively thorough in geographic coverage; all sites used in recent years, and new potential nest areas (i.e., newly excavated mining spoil piles) are visited (John Dinan, pers. comm.). One or more follow -up visits to nesting areas may be made to search for new nests, to determine status of previous nests and assess causes of nest losses, or to estimate productivity. Much of the data is collected by cooperators or by individuals with special research projects (e.g., graduate students). The records are maintained in a database by the Wildlife Division, Nebraska Game and Parks Commission, Lincoln. If multiple surveys of river sites are conducted, they are usually done through access by land. Surveys of nesting at sandpits are done by land. Where multiple visits are made to a colony, the counts from one visit in mid - nesting season is selected to represent the breeding census of that site. Who makes this decision? NGPC data entry person? Resolve and remove this statement When productivity is monitored by individual investigations, field surveys of nesting areas are conducted every other day or every third day to document the number of fledged young. The young birds are considered fledged if the plumage and coloration indicate the young to be at least 21 days old, or if the young are observed flying. Current investigations in the central Platte River study area compute the fledge rate by dividing the estimated number of fledged young by the number of nests attempted; a "nest attempt" is defined as a nest with a least one egg or young. A summary of locations and numbers of adult least terns and piping plovers surveyed in the central Platte River, derived from the database of the NGPC Wildlife Division, is provided in Tables 1 and 2, respectively. A written description of methods used by NPPD and CNPPID to monitor nests located at their sandpits and constructed river islands is located at Jenniges and Peyton 1999. Data collected through these means are reported to the NGPC and are included in Tables 1 and 2. Draft Baseline Report, July 2002 4 -6