Update from the Whooping Cranes' Winter Headquarters
Aransas National Wildlife Refuge
Austwell, Texas
February 26, 2001
This has been a bad year for the whooping crane. Despite a record 51 nesting pairs, production was low in Canada
in the summer of 2000. Although 30 chicks were present in June, only 9 completed the 2,500 mile migration and
arrived at Aransas. In addition, two of the 9 have died at Aransas this winter. Total numbers in the only natural
wild flock have plummeted. From last winter's record high of 188, there are currently only an estimated 176 whooping
cranes in the flock. A high number of birds died between the spring and fall, and 4 have died this winter.
This winter at Aransas, blue crab numbers are extremely low. Since the blue crab is the preferred food of the
whoopers (one crane can eat as many as 80 crabs per day), the cranes are having to find different kinds of food
to eat. Research has shown that although the whoopers can always find other foods, their overall nutrition suffers
and they actually lose energy when blue crabs are in short supply. This leads to higher mortality during the winter,
and may affect their ability to nest successfully in the upcoming summer.
Why aren't there enough blue crabs in the salt marshes for the cranes to eat? Texas went through a bad drought
last spring and summer. The lack of freshwater flowing into the bays raised bay salinities, and blue crabs don't
reproduce as well during drought. To make the natural drought even worse, human uses took much of the water from
the rivers so that not enough water reached the bays to keep them highly productive. This situation threatens
to worsen as more and more people move to Texas and water consumption expands. Resource agencies are working to
try to ensure enough water to help the bays which require a mixture of fresh and salt water.
I certainly haven't provided any good news for you. But keep in mind that the history of the whooping crane flock
is one of ups and downs, and that they have a record of bouncing back. Overall growth of the flock has averaged
3.7 % a year, but keep in mind that some years the population is going to drop. This is one of those years.
Tom Stehn, Whooping Crane Coordinator
U.S. Fish and Wildlife Service
Aransas NWR
P.O. Box 100
Austwell, TX 77950
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