Recovery efforts for endangered whooping cranes have included several initiatives to establish additional populations of the species via reintroduction. One or more additional populations would supplement the existing population that migrates between Aransas, Texas and Wood Buffalo National Park, Alberta. In 2001, a reintroduction of a migratory whooping crane flock began, with an intended migratory path between Wisconsin and Florida. The reintroduction has been accomplished with the release of birds imprinted on costumed people and ulralight aircraft to lead the birds on their first fall migration. This program has been successful in establishing migrating whooping cranes in the eastern United States. In 2006, a direct autumn release program was initiated where whooping crane chicks are costume-reared and released as a group in Wisconsin in the fall to find their own way south, usually in the company of adult whooping cranes. A third method was developed in 2013, in which the whooping crane chicks are reared in captivity not by costumed people, but by adult whooping cranes. The goal is to produce wild whooping cranes for release in the fall and to maximize opportunities for chicks to learn from adult whooping cranes. The chicks are moved from Patuxent each September to sites in Wisconsin, where they are released singly in the territory of adult whooping crane pairs. The goal is for each chick to form a bond with these allo-parents and migrate south with them.
Two parent-reared (PR) whooping cranes released in autumn 2013 survived the winter of 2013-2014 and remained with their allo-parents all winter. Whooping crane #22-13 spent the winter with adults at Hiwassee Wildlife Refuge in Tennessee. When these birds left to fly north, 22-13 accompanied them to southern Indiana. When the adults continued north from there, 22-13 remained behind, and only later flew north to Necedah National Wildlife Refuge (NWR). The young bird made several movements around Wisconsin and into Minnesota over the course of the summer. In late July, during an unusually cold spell with strong northerly winds, 22-13 flew to central Indiana. Later this crane returned north as far as Champaign County, Illinois, where he remained with some sandhill cranes until November 14, 2014. After a stopover in Tennessee, the bird arrived by November 18 on his previous wintering territory at Hiwassee Wildlife Refuge, in Tennessee. 22-13 is still in Tennessee as of the end of December, 2014.
Crane 24-13 was left behind by its allo-parents in central Kentucky when they migrated north in spring 2014. After several weeks alone in Kentucky, 24-13 migrated north on its own, following the path it had taken south, even stopping for a few nights at the same stopover area. Once back at Necedah NWR, 24-13 settled in some wetlands in southwestern Juneau County, Wisconsin, along with several other unpaired whooping cranes. In November 2014, 24-13 migrated south to Knox County, Indiana, with 3-11, 7-12 and 38-09. Three other whooping cranes have also joined this group where they remain in Indiana.
Six eggs were assigned to the 2014 PR project and all eggs hatched successfully. One chick was lost at 10 days of age due to a bacterial infection, and another chick lost to predation by a large black rat snake. All 4 remaining chicks were given 12 days of pond exposure before being shipped to Necedah NWR on September 19, 2014. Three temporary pens built on Necedah NWR and the former Operation Migration ultralight pen at site 4 were used for soft release of the cranes. The cranes were held overnight together at site 4, and then on the morning of September 20, with help from staff at the International Crane Foundation, all 4 cranes received satellite transmitter leg bands (platform terminal transmitters, PTTs), conventional VHF transmitter leg bands, and metal numbered Federal bird bands. After this, each crane was assigned to a temporary pen and monitored several times daily. After investigators determined that adult pairs were visiting the pen sites, the 4 cranes were released on September 22 and 23. For the next two weeks, the cranes were monitored closely and in all cases were seen associating with adults. In some cases, the chicks remained with the intended allo-parents, in other cases they associated with other pairs of adults.
One young bird, 21-14, flew northeast of Necedah NWR in early October. The signal was lost temporarily and ultimately the bird was found dead in a water-filled ditch. The body was taken to the USGS National Wildlife Heath Center for necropsy. The diagnosis was blunt force trauma, possibly from a collision with a motor vehicle, though the carcass was found about a half mile from the nearest roadway.
The other 3 released PR birds have survived to date. Crane 19-14 began migration with adult pair 7-07 and 39-07 on November 12, with short stopovers in Illinois and Kentucky. The bird arrived on the previous wintering grounds of the pair in Lowndes County, Georgia, by November 22. Crane 20-14 migrated south with 9-05 and 13-03 to Greene County, Indiana, where they have been joined by another pair of whooping crane adults. Crane 27-14 migrated to Hopkins County, Kentucky with 2-04 and 25-09. This is the wintering territory of 2-04, and where this male led 24-13 last year. The female, 25-09, is new, as 2-04’s previous mate died in the spring of 2014. These 3 birds have since been joined by 2 other pairs of whooping cranes.
We thank the whooping crane captive breeding institutions for providing chicks, and biological technicians from USGS Patuxent Wildlife Research Center, especially Rachel Roberts and Robert Doyle, for their extensive assistance with rearing chicks. We thank Cameron Stanek, Anne Harshbarger, and Rachel Roberts for behavioral observations of chicks, and Windway Corporation for transporting chicks. In Wisconsin, extensive help in pen construction and other aspects of the work was provided by Doug Stahler, Brad Strobel, Scott Collins, and other members of the staff of the Necedah National Wildlife Refuge. We acknowledge the work of Marianne Wellington, Rachel Koebert, Tiffanay Hudson, and Aubrey Klink from the International Crane Foundation for help with pen construction, banding, and post-release observations, and Eva Szyszkowski for help with banding and tracking cranes on migration.