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Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt

USGS Northern Prairie Wildlife Research Center

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over …

Timing Of Spring Surveys For Midcontinent Sandhill Cranes, Aaron T. Pearse, Gary L. Krapu, David A. Brandt, Glen A. Sargeant

USGS Northern Prairie Wildlife Research Center

The U.S. Fish and Wildlife Service has used spring aerial surveys to estimate numbers of migrating sandhill cranes (Grus canadensis) staging in the Platte River Valley of Nebraska, USA. Resulting estimates index the abundance of the midcontinent sandhill crane population and inform harvest management decisions. However, annual changes in the index have exceeded biologically plausible changes in population size (>50% of surveys between 1982 and 2013 indicate >20% change), raising questions about nuisance variation due to factors such as migration chronology. We used locations of cranes marked with very-highfrequency transmitters to estimate migration chronology (i.e., proportions of …

Spring-Migration Ecology Of Northern Pintails In South-Central Nebraska, Aaron T. Pearse, Gary L. Krapu, Robert R. Cox Jr., Bruce E. Davis

USGS Northern Prairie Wildlife Research Center

Spring-migration ecology of staging Northern Pintails, Anas acuta, was investigated in south-central Nebraska, USA. Habitat associations, local movements, settling patterns, arrival dates, residency times and survival were estimated from 71 radiomarked pintails during spring 2001, 2003 and 2004, and diet determined from 130 females collected during spring 1998 and 1999. Seventy-two percent of pintail diurnal locations were in palustrine wetlands, 7% in riverine wetlands, 3% in lacustrine wetlands, 6% in municipal sewage lagoons and irrigation reuse pits and 10.5% in croplands. Emergent wetlands with hemi-marsh conditions were used diurnally more often than wetlands with either open or closed vegetation …

Countability Of Sandhill Cranes In Aerial Surveys, Douglas H. Johnson, John W. Solberg, Courtney L. Amundson

Proceedings of the North American Crane Workshop

Aerial surveys are used to monitor populations of many wildlife species, including sandhill cranes (Grus canadensis). In addition to the usual problems of detectability (involving both availability and perceptibility), aerial surveys of concentrated animals are subject to countability issues; from a rapidly moving aircraft, observers cannot count or accurately estimate the number of animals in a large group. Calibration is sometimes performed in an effort to adjust aerial counts for incomplete detectability and countability by calculating the ratio of animals actually in a group to the number in the group estimated from the aircraft. Here we explore alternative, …

Management Of Lands Along The Platte River Fromelmcreek To Lexington, Nebraska, As Crane Habitat, James J. Jenniges, Mark M. Peyton

Proceedings of the North American Crane Workshop

To meet Federal Energy Regulatory Commission (FERC) license requirements for the operation of 5 hydroelectric power plants on the North Platte and Platte Rivers in Nebraska, the Nebraska Public Power District (NPPD) and The Central Nebraska Public Power and Irrigation District (Central) together have become the second largest owners and managers of lands for the conservation of endangered species and migratory waterbirds along the central reach of the Platte River. We describe here the management activities on the properties, success of the management in achieving objectives, and the response of sandhill (Grus canadensis) and whooping cranes (G. …

Contaminant Exposure And Reproductive Health Of Sandhill Cranes In The Central Platte River Valley, Nebraska., Matthew S. Schwarz, Christina D. Lydick, Karen J. Nelson, Timothy S. Gross

United States Fish and Wildlife: Staff Publications

The central Platte River Valley provides crucial staging habitat for the endangered whooping crane (Grus americana) and the mid-continent population of sandhill cranes (Grus canadensis). Platte River flow depletions and the conversion of native wet meadows for agriculture and other purposes has decreased the cranes natural habitat in the central Platte River Valley, and waste corn now makes up most of the cranes diet while they are in the Valley.

The purpose of this research was to measure organochlorine, elemental contaminant, and pesticide exposure to sandhill cranes from the central Platte River Valley, and to evaluate their reproductive condition. Pesticides …

Nocturnal Roost Site Selection And Diurnal Habitat Use By Sandhill Cranes During Spring In Central Nebraska, Craig A. Davis

Proceedings of the North American Crane Workshop

During spring 1998 and 1999, the Platte River Whooping Crane Maintenance Trust conducted ground and aerial surveys of staging sandhill cranes (Grus canadensis; hereafter, cranes) to detennine roost site selection and habitat-use patterns along a l20-Ian stretch of the Platte River in south-central Nebraska. Cranes peaked at 232,023 during 22-28 March 1998 and 206,074 during 28 Februaty-6 March 1999 in the study area, a portion of the total crane staging area in the Platte River Valley. Diurnal observations showed that 48% of the cranes were in com fields, 34% in lowland grasslands, 13% in alfalfa fields, and 5% …

The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski

School of Natural Resources: Faculty Publications

Habitat fragmentation has been implicated as a major cause of population decline in grassland birds. We tested the hypothesis that a combination of area and shape determines the use of grassland patches by breeding birds. We compared both species richness and individual species presence in 45 wet meadow grasslands in the floodplain of the central Platte River, Nebraska. Bird data were collected through the use of belt transects and supplemented by walking and listening outside transects. Our data supported our primary hypothesis that perimeter–area ratio, which reflects both the area and shape of a patch, is the strongest predictor of …

Woody Vegetation Expansion And Continuing Declines In Open Channel Habitat On The Platte River In Nebraska, Paul J. Currier

Proceedings of the North American Crane Workshop

Aerial videography in 1988 and 1994 of the same selected segments of the Big Bend reach of the Platte River in central Nebraska was compared. During this 6-year period, channel area declined 4 to 41 % (median 26%). In river segments where the channel had already narrowed significantly and at sites where channel habitat is actively managed declines were less (17-18%). These substantial changes occurred during a time that included a relatively low flow period (1990-92). Flows during the summer gertttination and establishment period (mid-May through August) for cottonwood (Populus deltoides) and willow (Salix spp.), the …

History And Economic Impact Of Crane-Watching In Central Nebraska, Gary R. Lingle

Proceedings of the North American Crane Workshop

The first documentation of the Platte and North Platte rivers' importance to sandhill cranes (Grus canadensis) dates from the late 1800's. Except for a few ornithologists, it was not until the mid-1970's that crane-watching became popular. During the last 10 years, this interest has become a multi-million dollar tourist industry that attracts people from around the globe who seek to witness this vernal spectacle of half a million cranes. More than half of the former riverine habitat has been abandoned by the cranes, largely because of irrigation and hydropower projects that drain the river and enable forests to …