They line up facing nor-nor-west, looking into the middle distance, sullen, appearing to not care about their fellow travellers.
There is no squabbling, no feeding and no preening. Just a resolute stare toward the horizon.
Then, on an invisible cue, the wings expand, the birds rise, screaming and egging each other on, and they’re off.
To Russia.
These are the last moments of the bar-tailed godwit on Australian soil (for a year anyway).
‘When they lift off into the air, they start calling to each other like it’s the most exciting thing they’ve ever done.’
In their lifetime, some of the birds will fly the equivalent distance of a trip to the Moon and back. That’s 700,000km spent seeking seasonal food in sites like the Arctic tundra.
‘The next big place that they need to make it to is South East Asia—one of the big places is the Yellow [Sea] between Korea and China.’
By the time the birds arrive at the halfway point in Asia, almost all their body fat has been used in the flight.
‘They’re kind of skin and bone and feathers and they need to put on that weight again. They have these two massive weight gain periods that they need to go through to make that trip up to the Arctic,’ says Clemens.
‘One of the issues that’s impacting these birds is the loss of habitat that’s happening in the Yellow Sea. Work at the University of Queensland has highlighted that anywhere from 50 per cent to two thirds of the intertidal habitat that these birds rely on has been lost over the last 50 years or so.’
The Yellow Sea is a bottle neck in terms of shorebird migration, one of the critical and highly used stop-over points in the East Asian-Australasian flyway.
In 2007 Birdlife Australia reported that 150,000 shorebirds simply did not reappear on the return journey from the north. The cause was found to be the destruction of a patch of intertidal zone in the Yellow Sea.
The problem with habitat destruction of such a mobile group of species is that researchers do not see the result of, say, a golf course development on the Chinese shoreline until a year later when whole flocks of birds simply do not appear on their way out of Australia again; they’ve starved somewhere on their journey.
Various organisations help to monitor the numbers of birds that migrate through Australia, which are thought to hover at around five million in total.
However, in the 25 years of monitoring, many migratory bird species have been declining rapidly, such as the curlew sandpiper, whose population has decreased by 50 to 80 per cent.
As the birds have almost all flown out to the north for this year, twitchers all over Australia are wishing them well, waving farewell, and hoping that this time, it isn’t forever.
read more: http://www.abc.net.au/radionatio ... tion-begins/5442242 作者: sucewang 时间: 10-5-2014 23:16
“山东大姐”的帖子一定要顶！
前些天还在心里念叨你呢！作者: 山东大姐 时间: 11-5-2014 00:16
