Autumnwatch’s Chris Packham and Martin Hughes-Games on the heroes of migration

In the skies and rivers of Britain, animals are on the move...

1. Stalin’s Starlings

Advertisement

Britain’s shrinking population of starlings will soon be swollen by millions arriving from colder parts of Europe such as Poland, Germany and Russia. “As eastern Europe freezes they’ll come over here for the soft soil,” says Chris Packham. It’s hoped that upwards of 100,000 will settle at this year’s Autumnwatch location at RSPB Leighton Moss near Morecambe Bay, Lancashire.

In some areas of the UK, numbers of resident starlings have fallen by 90 per cent in the past 25 years due to intensive farming, says Packham. It’s all a far cry from 1930s and 40s when, in East Anglia alone, there were populations of 40 million starlings roosting.

“During Stalin’s era it was realised that starlings were effective at pest control so farm workers were ordered to put up hundreds of thousands of nesting boxes all over the Russian corn belt,” says Packham. “The starlings were therefore breeding in super abundance, feeding on the pests in the fields and then coming here in the winter. So those huge numbers of starlings were due to Stalin.” 


See nature in all her glory on a trip with Radio Times Travel, see here for more details


2. An American Odyssey

The story of the Manx shearwater’s migration puts it at the top of the pile for dogged belligerence. The chicks are fed and fattened up by their parents in their burrows on islands and coastal cliffs around Great Britain but then abandoned as the adults leave for South America. The chicks then wait for a moonless September night before emerging from their burrows to walk and fly for the first time — and then spend between two and three years at sea.

“What’s incredible is that they have to learn to fly, hunt and make their way to South America without any help from their parents,” says Packham. “Those young birds won’t come back to breed for a few years so they will just be at sea for all of that time.“

Because their migratory habits are predictable — the adults return to the same burrows to breed every year — scientists have been able to gather huge amounts of evidence about their wanderings by attaching a tiny data-collection device to the birds.



See nature in all her glory on a trip with Radio Times Travel, see here for more details


3. Slip, Sliding Away

The need to breed is what compels eels to leave our riverbeds and begin a final journey to the Sargasso Sea in the North Atlantic. Though numbers have fallen dramatically, reports this autumn suggest a huge exodus. “When I was a kid I used to go down to the local river to help empty the eel traps,” says Chris Packham. “We were filling oil drums out of this trap every night. In recent years there’s been a catastrophic decline in numbers, yet this year, for reasons we don’t understand, people are saying that there are masses — just like the old days. They will typically ‘run’, or move through the river, after heavy rain. On rainy nights they can move overland.

“Only once have scientists ever been able to induce a female eel into a breeding state in a tank. They will only get into that state when they reach the Sargasso Sea at a depth of about 200m (650ft). And those tiny eels, which are like little sycamore seeds, then find their way back to our streams.

4. Catching a Ride

Silver Y moths, named after the markings on their wings, leave our shores in autumn for the journey to North Africa, hitching a lift on fast, high-altitude winds. “In terms of numbers, they far exceed all the migrating birds put together — there are millions and millions of them,” says Autumnwatch’s Martin Hughes-Games. “After they’ve hatched out, they wait for a southerly wind, then they rise up until they hit the most forceful part of the current, and off they go. They can go up to 60km an hour (37mph). They’ve got an internal compass, so if the wind isn’t taking them where they want to go, the moths fly at a slight angle to enable them to adjust their position.”

Autumnwatch starts tonight at 8:00pm on BBC2


 



Advertisement

See nature in all her glory on a trip with Radio Times Travel, see here for more details