International Crane Foundation


Whooping Crane Research at Aransas NWR: Well Worth the Wait

Our scorecard: week one: 1 bird, week two: 10 birds! ICF’s Director of Veterinary Services Dr. Barry Hartup (below, in blue, photo by Aaron Pearse, USGS) returned earlier this month from a two-week field visit to Aransas National Wildlife Refuge (NWR) in Texas to capture and band Whooping Cranes. The researchers successfully banded 11 birds as part of a study to learn more about the movements and health of the western Whooping Crane population. The team finally experienced the success they’d hoped for since 2009 due to creative innovation and persistence.


The team, including Dr. Hartup, David Brandt from the USGS Northern Prairie Wildlife Research Center, Felipe Chavez-Ramirez, Gulf Coast Bird Observatory, and Walter Wehtje of the Crane Trust, banded the cranes at eight fresh water holes on the Blackjack Peninsula portion of the refuge.

The researchers regularly saw 10-20 different Whooping Cranes visit each of the water hole sites in a given day. Conditions were dry, but punctuated by two rainy days that helped recharge the ponds with fresh water (especially to the south where the team sat wet and huddled in a blind one morning). An arctic air mass moved in part-way through the field work, which lowered temperatures and seemed to focus the birds’ attention on corn bait piles once they came off roost in the salt marsh. The birds were caught by use of a non-traumatic, remotely triggered snare system and quick action of the team. All birds were processed (banding, measurements, health exam and samples taken) in under 20 minutes, most in less than 15. All birds flew away strongly and were accounted for visually or via their GPS telemetry units within hours or days of capture.

The cranes appeared to be eating a lot of wolfberries and only an occasional blue crab. Dr. Hartup collected a couple dozen stool samples for stress hormone (corticosterone) testing to complement a health assessement study of the captured cranes sponsored by the University of Wisconsin School of Veterinary Medicine Companion Animal Fund.

 Members of the field team at one of the fresh water capture sites. The Aransas NWR recently burned this area for the benefit of Whooping Cranes that feed on acorns and other plant and animal resources available in these opened upland habitats (learn more about the prescribed burn program at Aransas NWR). Pictured L to R: David Brandt, USGS; Felipe Chavez-Ramirez, Gulf Coast Bird Observatory; Barry Hartup, ICF; Walter Wehtje, Crane Trust. Not pictured: Brad Strobel, USFWS; Dan Rousseau, Aransas NWR Student Conservation Association intern; Aaron Pearse, USGS; David Baasch, Platte River Recovery Implementation Program. Photo by David Baasch.

The Guadalupe River basin (click on map to enlarge)

learn_moreLearn more about the affects of the 2011 Texas drought on the wintering Whooping Cranes.

Read our field update and view our video from the team’s August 2011 expedition to the Whooping Crane’s remote breeding grounds at Wood Buffalo National Park in central Canada.