Endangered whooping crane follows aircraft in unique migration

These endangered whooping crane, pictured flying through the air in V-formation, are seen making the long journey south in a unique human-led migration.

11:12AM BST 22 Apr 2009

Travelling 1,250 miles over a three-month period the birds follow a specially constructed ultralight aircraft from central Wisconsin to the west coast of Florida each October.

The journey is the result of efforts by conservationists to increase the population of whooping cranes in the wild, which had declined to just 15 in 1941, although numbers have now risen to approximately 200.

To combat the threat of extinction of North America's tallest bird, US Fisheries and Wildlife Services teamed up with the Whooping Crane Recovery Team to breed a secondary flock who will migrate down the eastern seaboard.

Led by conservation group, "Operation Migration", the annual journey from Necedah National Wildlife Refuge in Wisconsin, sees as many as 20 whooping cranes making the trip south to the Florida refuge.

"The total migration distance is 1,250 miles and the migration takes around 80 days to complete," said 59-year-old lead pilot Joe Duff.

"The problem with reintroducing these birds is they learn the migration route by following a parent.

"As there is no parent generation we become the surrogate parent and we teach them to follow our aircraft and we lead them on their first migration.

"Thereafter they are on their own and they return as wild birds."

Mr Duff and his team, who are to be awarded the Conservation Partners Award from the Department of Interiors in Washington this week, have led over 100 birds south in this secondary migration project from 2001.

The complicated process begins before the birds are even born.

"We start the procedure at the Patuxent Wildlife Research Centre in Maryland where the largest captive flock of Whooping cranes are kept," he said.

"We start playing the sound of the aircraft carrier engine and the brood call before the egg hatches.

"Once the birds are about 50 days of age we ship them out to Wisconsin before they learn to fly because once they earn to fly then the first thing they see from the air is where they home to."

Using a specially constructed ultralight, complete with cameras, GPS system and an amplifier system to broadcast calling sounds, Mr Duff and his four man team can cover 50 to 100 miles per day at a speed of 38mph.

However, conditions can only be achieved during smooth air conditions, which restricts flying time.

"We can only fly for that very calm cold period first thing in the morning right after the sun rises when we only get an hour of dead calm air.

"So we have to wait for calm days and for days where there is no ground fog or until the frost clears in the mornings so we have a very narrow weather window we can use."

http://www.telegraph.co.uk/news/newstopics/howaboutthat/5197464/Endangered-whooping-crane-follows-aircraft-in-unique-migration.html