Dr. Wade Harrell, U.S. Whooping Crane Recovery Coordinator reports that whooping crane field tracking efforts resulted in 13 marked birds this winter. Harrell stated that “68 whooping cranes have been marked with GPS transmitters during the past four years. This is the last season of capture and marking of whooping cranes in Texas.”
Harrell explained that “GPS units are attached to a bird’s upper leg and record four to five locations every 24 hours. Information on the marked whoopers is uploaded to a satellite every two and half days. These data reveal migration routes, habitat use, nesting locations, and much more. Biologists in the United States and Canada will use results of this work to identify management and conservation priorities in both countries.”
Back on the Aransas Refuge this year some interesting changes were detected by Biologists. More whooping cranes were located in the primary refuge survey area and fewer individuals were documented outside the
primary survey area. Dr. Harrell pointed out that, “Long-term whooping crane followers likely remember that over the last couple of years many whooping cranes spent much of the winter outside of the primary survey area. This was likely due to a number of factors including overall population expansion and ongoing drought conditions.”
Harrell advised that “the differences in the whooping cranes geographic shift among years may be due to shifts in food resource availability. While it was still a relatively dry year, some timely rains this past summer and early fall may have contributed to greater food resource availability in area coastal marshes. This may indicate that whooping crane behavior is adaptable and individual birds are able to shift their habitat and food use in relation to local environmental conditions. It provides a continued hope that the whooping crane population is resilient in the face of fluctuating environmental conditions such as drought. Wintering in a variety of places across a broader geographic range reduces the risk that a single localized catastrophic event could cause extinction.”
To read more, go to: http://www.fws.gov/nwrs/threecolumn.aspx?id=2147546801
