Biological Technician Sally Zodrow (l) and YCC Crew Leader Paul Flahave assist Matt Hayes (r) from the International Crane Foundation as he draws blood for genetic analysis from a flightless Greater Sandhill Crane chick at Sherburne NWR. 7/9/2007. - FWS photo by by J. Holler

Even though sandhill cranes are known to be one of the oldest living birds recorded in the fossil record, there is still much to learn about them.

The Eastern Flyway Population of Greater Sandhill Cranes is particularly interesting because it is rebounding from an all time low in the early 1900's when there were less than 50 breeding pairs in Minnesota, Wisconsin, and Michigan combined, and they became totally absent from eastern Canada, Illinois, Indiana, and Ohio. 

The population has been slowly, but steadily increasing and re-colonizing former breeding areas such as Sherburne National Wildlife Refuge since the mid-1900's. To help better understand the structure and function of this population, the Refuge served as one of six study sites for research being undertaken by the International Crane Foundation. 

Eleven flightless crane chicks were caught in early July, eight of which were captured on the Refuge and three on nearby private land. Each had their blood drawn and a series of colored and numbered bands placed on their legs. The genetic analysis performed on their blood will show how related they are to other cranes nesting in Wisconsin and Michigan.

The bands will them to be identified in the field and will help confirm what areas they use as stopovers in migration, if they come back to the their natal areas to nest, and if they intermingle with any of the other populations. By serving as a research area for studies like this, the Refuge contributes to larger wildlife conservation efforts.