Tom Stehn's Report: Good News, Bad News
Feb. 12, 2010
Meet Tom Stehn
Whooping Crane Coordinator, U.S. Fish and Wildlife Service

As you read Tom's report this week . . .
  1. How many cranes were at Aransas NWR when Tom first counted them in 1982? How many are there today?
  2. What is unusual about this winter and last winter at Aransas?
  3. What do Whooping cranes need in good winter habitat? Why?
  4. Who is Scarbaby?

 

Dear Journey North Kids,

Only 73 whooping cranes were present for winter when I did my first Whooping crane count in fall 1982. The good news is that the flock grew. I don't have an exact number yet but I estimate the flock size at 244 adults + 19 juveniles = 263. Counting has been hard: The territories of adult cranes remain difficult to figure out because many of the crane pairs have left their marsh and are searching for food on the uplands. The poor habitat conditons of last year are still a problem. Last year was my most frustrating winter at Aransas. We lost 23 birds (8.5% of the flock). Two Whooping cranes failed to migrate north, but survived the hot and dry 2009 Aransas summer. We're concerned that this will be another precarious winter for this flock. We have just one or ZERO crane deaths in normal winters. Why is this happening?
Drought is causing problems in crane habitat. Cranes eat wolfberries when blue crabs are scarce. But these berries are now scarce too. Blue crabs are the most important winter food for cranes. Drought has made them scarce.

Food and fresh water for the cranes is scarce because of the prolonged drought, or period of dryness, in Texas. Hungry cranes were arriving in November after their 2,700-mile migration from Canada. Not only are their normal marsh foods scarce, but the drought has made the marsh water saltier than cranes can drink. They must spend precious energy to fly farther in search of fresh drinking water. (A crane in flight uses an estimated 19 times more energy than a crane at rest.) Their winter habitat is not nourishing them after their long migration from Canada. Summer nesting was affected the poor blue crab winter at Aransas. Last summer's 22 fledged chicks from 62 nests was only half the production of the previous summer.

But there's good news too. I expected a break-even year, but so far it's better. And you will hear about some of the wonderful crane individuals and pairs I have come to know in my years at Aransas. You'll agree that their stories give us a lot to celebrate. We'll start with the story of a male called Scarbaby. How did he get that name? What is so unusual about his history? How did he fare during the harsh winter last year? Where was he last summer? Will he someday have a great record like his father? Scarbaby's Triumph is his story. And it's not yet finished. Good!

Tom Stehn
Aransas National Wildlife Refuge
Austwell, Texas