The Crane Trust conducts research on whooping and sandhill cranes and their habitats; wet meadow utilization; prairie restoration and management; adaptive management of restored/remnant grasslands using monitoring data; rapid evolution of ground water chemistry during drought; distribution effects of river woodlands on mammalian species; and survey methods for diurnal birds of prey. Explore several topics in more depth below.
» WHOOPING CRANES
The Aransas-Wood Buffalo whooping cranes belong to the only self-sustaining population in existence. Currently at about 300 birds, their numbers are increasing but still remain threateningly low. Scientists have learned that one of the times when young cranes face the most risk is the two to three months when they migrate between their Canadian breeding grounds and Texas winter home.
Since 2009, the Crane Trust scientists, in cooperation with the USGS Northern Prairie Wildlife Research Center, the US Fish and Wildlife Service, the Platte River Recovery Implementation Program, and the Canadian Wildlife Service with support from the Gulf Coast Bird Observatory, International Crane Foundation, and Parks Canada have placed GPS transmitters on more than 60 whooping cranes in Canada and Texas. These transmitters provide us with as many as four locations for each bird per day. This allows us to follow the cranes’ movements and learn more about their migration habits and habitat between Wood Buffalo National Park and Aransas National Wildlife Refuge.
Recent captures have met study plan objectives and no new capture activities are currently planned. We expect to collect data through 2016. Already, we have learned much about the timing of the cranes’ movements, where they stop during migration, and how they use their winter and nesting habitat. The results of this study will give us a better understanding of crane migratory behavior and may help us to assess the risks whooping cranes face on their yearly 5,000 mile round trip.
This project began with pilot data collection by personnel of the Platte River Recovery and Implementation Program and Crane Trust at sites used by marked cranes in Nebraska during spring 2012 and fall 2012 migrations.
In 2013, the Program and researchers from the USGS and Crane Trust conducted a ground-based study spanning from northern Texas to North Dakota and evaluated habitats that telemetry-marked whooping cranes used as stopover sites during migration.
Knowing what habitats whooping cranes select, and potential resources available from those habitats, is essential for management of the species. We seek to visit and characterize stopover sites used by whooping cranes from the Platte River to document surrounding habitat characteristics and land management practices to better define minimum habitat criteria required by the species.
Whooping cranes are a rare and often elusive species, and much is still unknown about their migratory cues and other natural tendencies.
The Crane Trust seeks to further the understanding of this species and is constantly on the lookout for unusual or undocumented behaviors by whooping cranes, such as happened during the winter of 2011-2012. Read more.
» Sandhill Cranes
Sandhill Crane Roost Surveys
Each year in early February the Crane Trust begins its aerial surveys of sandhill cranes along the Big Bend reach of the Platte River, continuing a long-term monitoring project that began in 1998.
The survey covers an 80-mile stretch of the Platte River from Overton, Nebraska, on the western edge of the primary staging area for sandhill cranes, to Chapman, Nebraska, which approximates the eastern edge.
Once a week members of the survey team fly the 80-mile route at dawn to visually estimate and record the number and location of sandhill cranes roosting on the river. Because not all sandhill cranes are in Nebraska at any one time, let alone the confines of the Platte River, these surveys provide an index of crane use and migration timing from year to year, and not the actual population. Surveys have been made possible with the aid of Grand Island resident/pilot Lonnie Logan, who has generously volunteered his time and private airplane to support the effort since 2012.
The roosts along the eastern portion of the route—notably the Alda roost south of Crane Trust headquarters—often contains the highest densities of birds during the first month of the migration. Importantly, this is a region of the river that the Crane Trust has managed intensively by clearing vegetation from the active river channel. From both ground and aerial observations, this habitat improvement has had a positive impact on crane utilization of this portion of the river.
While particular stretches of the river between Grand Island and Kearney are traditionally favored by sandhill cranes, day-to-day use of the channel varies, depending on several factors. Shortly after water levels recede many sandbars are exposed and birds are found in loose congregations. In contrast, when water levels are high or when cold, windy weather threatens, the cranes are often tightly packed on the most favorable roosts and in protected pockets on the river.
These ongoing roost surveys are an important component of the Crane Trust’s monitoring program, enabling the Trust and other conservation partners to better assess and understand the effects of different habitat management practices on cranes at this critical stage in their annual migration. The surveys continue into mid-April when most cranes will have left the river to continue their migration to breeding grounds in the north.
Studying Sandhill Cranes Using Time Lapse Photography
Wet meadows adjacent the Platte River provide important migratory, feeding, and nesting habitats for more than 150 species of birds and other wildlife in central Nebraska. Most wet meadows of the Platte River Valley have been drained and/or converted to cropland and other uses over the last several decades. As a result, wet meadows are now rare along the Platte River relative to their historical distribution.
The objective of this research is to understand how wet meadows and the Platte River serve sandhill cranes staging in the Central Platte River Valley during spring. Thousands of images have been captured and analyzed to determine how sandhill cranes interact and obtain resources while in Nebraska. The images we have acquired allow us to see cranes as they’ve never been seen before and are both fascinating and educational. The Crane Trust is currently studying images to summarize findings and learn how new technology can be applied to studies of animal behavior. This material has been formatted to serve as an outreach tool to help the public understand just how special Platte River habitat is to migratory birds, and to offer a glimpse of the untold beauty made possible by Crane Trust lands.
» American Bison Herd
Historically, the American bison was a common sight in Nebraska. Their 150-year absence from the Platte River Valley has prompted land managers and researchers to speculate the impacts the vast herds of these animals once had on grasslands and wet meadows along the Platte River.
At the Crane Trust, cattle grazing is used to manage vegetation in a way that promotes healthy habitats and high biodiversity. Various grazing systems have been used on Crane Trust properties, and ultimately the recipe for sustainable grasslands has included doses of grazing, rest, fire, and some mechanical means of vegetation control. As management changes and we adapt to the new things science tells us about maintaining critical Platte River grasslands, we strive to research and understand as much about how management affects the plants and animals that inhabit these lands as possible.
Now, those studies can have a new focus as we have reintroduced bison to some properties near our headquarters on Shoemaker Island. Currently we are researching how bison impact upland and lowland plant communities relative to cattle. In the future, we plan to expand studies to include bison-crane interactions, both direct and indirect, as a means of learning how the addition of this historic grazer can benefit migratory birds.
The Crane Trust owns and manages lands that are dominated by wet tall-grass prairies also called “wet meadows”, a habitat type that is now rare in the Great Plains due to changes in land use and alteration to river flows.
The Trust actively manages its lands by burning grasslands and grazing cattle and bison, in an effort to mimic natural disturbances by wildfire and bison grazing that once shaped this ecosystem. Wet meadows associated with the Platte River vary in local topography, with water-filled, linear depressions, known as sloughs, surrounded by drier upland habitats, that combined create a diversity of habitats for wildlife and plants.
Crane Trust properties are adaptively managed, which means that our management prescription differs from one year to the next dependent upon a variety of both habitat and climatic conditions. The best way to understand the condition of these habitats involves monitoring the plants and animals that call them home. It is for this reason that Crane Trust researchers, technicians, and interns are actively engaged in long-term evaluations of birds, reptiles, amphibians, small mammals, and plants.
Monitoring comes in a number of forms, but one of the key efforts conducted by the Crane Trust is the annual monitoring of sandhill crane roost distributions throughout the entire Central Platte River Valley. This effort has been ongoing since the late 1990’s and involves weekly airplane flights during spring to estimate the number and map the location of cranes along the river.
Grassland birds are sensitive to encroachment by woody plant species and trees. Therefore, another annual monitoring effort involves documenting the presence of specialized grassland species such as upland sandpipers, dickcissels, eastern kingbirds, grasshopper sparrows, and many others.
Cranes, shorebirds, and migratory waterfowl all depend on water, and especially so when they stage along the Platte River during migration. Like wildlife, surface and groundwater variations respond to our management as well. The effect of evapotranspiration can cause noticeable water declines, and the Crane Trust monitors a series of sloughs and wells on Mormon and Shoemaker Island to assess long-term and short-term trends of water levels in relation to human-induced and climatic factors.
Collaborative research is underway between researchers at the Crane Trust, universities, and other conservation organizations to study these interactions. Because the Trust manages some of the largest areas of wet meadow habitat remaining on the Platte, it serves as a reference for how parts of the river may have functioned historically. Results of these studies will help people understand the diversity and abundance of vertebrates and vegetation that may have once existed in other parts of the Platte River. Results also will assist the Trust in evaluating the success of its land management activities for supporting a diversity of organisms.
» Guest Researchers
In addition to internal research and monitoring efforts, the Crane Trust provides aid in the form of study site, lodging, facilities, expertise, and equipment to a number of guest researchers.
From high school to doctoral students, the Crane Trust supports guest researchers that seek to further the Trust’s mission of science and adaptive management for the protection of habitat for cranes and other migratory birds.
Such research has made a tremendous contribution to our base understanding of both the wildlife and habitat found within the Central Platte River Valley. Some recent examples of guest research are listed below.
Theses & Dissertations
- Anderson, J. D. 2012. Influence of habitat heterogeneity on small mammals in the Central Platte River Valley, Nebraska. M.S. Thesis. Fort Hays State University
- Barceló Llanes, I. 2012. Winter ecology of sandhill cranes (Grus canadensis) in northern Mexico. Ph.D. Dissertation. University of Nebraska.
- Buckley, T. J. 2011. Habitat use and abundance patterns of sandhill cranes in the Central Platte River Valley, Nebraska, 2003-2010. M.S. Thesis. University of Nebraska.
- Morton, M. J. 2011. Seed dispersal by wind and birds in a tallgrass prairie: implications for grassland management. M.S. Thesis. University of Nebraska at Kearney.
- Ramírez Yanez, L. E. 2011. Impact of alternative range management systems on grasslands in the central Platte River Valley, Nebraska. Ph.D. Dissertation. University of Nebraska.
- Vivian, L. A. 2010. Updates on the distribution and population status of the Platte River caddisfly, Ironoquia plattensis, and an assessment of threats to its survival. M.S. Thesis. University of Nebraska at Kearney.
» Reach Program
REACH (Research Experience to Achieve Conservation of Habitat) is a major training initiative launched by the Crane Trust with aid by a grant from the Nebraska Environmental Trust (NET) to improve the restoration of habitat for cranes and other migratory birds along the Platte River.
The innovative new conservation-training program is being led by Crane Trust staff with help from conservation partners, and offers interns, technicians, and students valuable hands-on experience to prepare them for careers in the conservation field.
The sweeping new program combines hands-on training and field experience for graduate and undergraduate students with the pressing need for targeted resources to evaluate and improve conservation practices wherever possible. Importantly, the REACH program also focuses on developing new ways to effectively share and communicate outcomes with key audiences. Developing time-lapse videos of crane behavior and fluctuating conditions on wet meadow habitat is but one example.
The program has three primary objectives:
- Evaluating habitat restoration and enhancement activities along the Platte River in conjunction with conservation partners.
- Sharing different conservation strategies and outcomes with the research community, conservation partners and other publics to further conservation gains through improved resource management practices.
- Providing emerging conservation leaders with important training and background on the natural history of the Platte River and other Nebraska ecosystems.
With core program funding NET the Crane Trust recruited six interns this summer to work under the guidance and tutelage of Crane Trust staff and other research/conservation partners. REACH interns work and live on campus at the Crane Trust’s Wild Rose Ranch on the Platte River.
Interactions with other conservation partners are important in the REACH program’s design, helping to broaden the range of experience and training for interns. For that, the Crane Trust is grateful to the Central Nebraska Public Power & Irrigation District, Central Platte Natural Resources District, Nebraska Game & Parks Commission, Platte Basin Time-Lapse Project team, Platte River Recovery Implementation Program, The Nature Conservancy, University of Nebraska–Lincoln, University of Nebraska at Kearney, U.S. Geological Survey and others for their time and effort towards this project.
One of the program’s most exciting aspects is that it cuts across so many lines, providing vital feedback at every turn. On any given day interns can be conducting field surveys for a diverse range of species, editing time-lapse photography, analyzing crane behaviors, or assisting with land management activities. That integration is important for improving program efficiency and collaboration—and for nurturing a new generation of conservation leaders.
A past REACH intern’s perspective says it best:
“The REACH program was one of the best opportunities I could have gotten as the first step in my career after college. The program got me directly involved in key aspects of conservation that went far beyond what I was taught in school. As an intern I participated in public outreach, land management, scientific research, and helped collaborate with the Crane Trust’s conservation partners. I learned that this diversity of activities is essential for the success of any conservation effort. Personally interacting with professionals who worked in each of these areas not only made me a better-rounded individual but also had great lasting effects for me in the next phases of my career. In the time since I completed the REACH program the people I made connections with at the Crane Trust have helped me gain new opportunities and succeed in my future jobs by being important resources of knowledge and support.”
– Julia Clymer, 2013 REACH intern