It is a question people have pondered for centuries: how do migrating birds
navigate between breeding and wintering grounds? Do they have some genetic GPS
to steer them along time-honoured routes, or do they learn the way from parents
or elders in migrating flocks? New research shows that, in the case of the
endangered Whooping Crane of North America, the birds do learn routes from older and more experienced companions — and all of them become better at navigating with age and experience.

University of Maryland ecologist Thomas Mueller and colleagues took advantage
of eight years of detailed migration data compiled on birds bred in captivity
and released in Wisconsin's Necedah National Wildlife Refuge for a journey to
their Florida breeding grounds. Flying groups that include a migration-savvy
seven-year-old crane veer off course 38% less often than groups in which the
oldest birds are only a year old, according to an eight-year study of Whooping
Crane migration between Wisconsin and Florida. On average, the one-year-olds
that don't follow older birds veer off the flight path by 60 miles (97km). But
the cranes' migration ability improves steadily with age, the study shows.
Groups with even one of these older birds deviate less than 40 miles (64km), on
average, from the most efficient route.

 Other likely variables for navigation success, including gender and the size
of flying groups, appeared to make no difference in the results. Mueller, a
co-author of the study, and his team theorized that the older birds recognize
landmarks better and may also know how best to cope with bad weather — two
skills they apparently pass on to the young birds that follow their lead. "As
the oldest bird in the flying group gets older, it seems that there's dramatic
improvement in its migratory efficiency for about the first five years," Mueller
said. "There is a very big difference if the oldest bird in a flying group is
one or two years old or if it's five or six or seven years old. A bird can be
pretty young and still have great success," he added, "as long as it flies with
a bird that is pretty old."

What's new?
Previous studies have suggested that learning plays some role among migrating
species. However, as Mueller cited, what is new here is that learning takes
place over a number of years and the older birds are crucial to the development
of the younger birds. Mueller explained: "That was difficult to look at before
because the data simply didn't exist. Usually tracking data on animals lasts for
a year or two years if you're lucky."

As part of unprecedented efforts to save and reintroduce the species,
scientists collected data to gauge the success of breeding, training, and the
birds' subsequent 1,300-mile (2,100km) migration. Individual birds were
identified and tracked with satellite transmitters, radiotelemetry, and human
observers. "Usually you don't even know if a bird is two or three or four years
old," Mueller continued. "There are lots of [previous] comparisons between
juveniles and adults, but here we had the full progression of many years as well
as the information of how old the birds were, how they were related to one
another, and exactly where and when they migrated."

What does this mean?
The Whooping Crane research is important new evidence showing how bird
migration is, at least in part, a learned skill. But it won't put to rest the
long-running debate on the respective roles played by genetics and social
learning.

 In fact, Mueller said, the study suggests an interesting combination of
genetics and learned behaviour at work. It begins when the time comes for the
cranes' first autumn flight to their southern wintering grounds and the
captive-bred animals are actually guided by humans who fly ultralight aircraft
all the way to Florida. "If you think about even that initial migration, it
needs to be at least somewhat learned," he explained. "They may have a natural
tendency to migrate in the fall, but we don't think many would get anywhere
where they could survive without some training."

 But genetics do begin to play a more easily visible role on the return trip,
he added. "Then after they've been shown the route once, in the spring they know
it's time to initiate a return and there's a genetic component in play there.
Because nobody has showed them this, so it's genetics combined with the learned
knowledge from the trip south in the fall."

 What's next?
Co-author Sarah Converse, a research scientist with the U.S. Geological
Survey's Patuxent Wildlife Research Center, has worked extensively with the
Whooping Crane Eastern Partnership, which runs the eastern migratory population
reintroduction program. She said: "Our results suggest that an effort to restore
Whooping Crane populations isn't just an effort to restore a biological
population, but also an effort to restore a culture, where knowledge is
transmitted across generations via learning, rather than genetics."

 "We can imagine that the low breeding success that we are currently
struggling with in this reintroduced population might actually improve over
time, with increased experience and learning of appropriate breeding behaviours.
For example, maybe chicks learn from their parents how to themselves be
successful parents. Overall, these results suggest that patience may well be
important if we hope to restore migratory Whooping Cranes to eastern North
America."

A rare sighting of a marked Spoon-billed Sandpiper on migration was reported last weekend from Rudong mudflats north of Shanghai. The critically endangered bird was identified by a lime green plastic flag on its leg marked '01' that was
attached by scientists from Birds Russia on its breeding grounds this
summer.

Conservationists know that this bird 'Lime 01' fathered six fledglings this
summer — three that were hand-reared by conservationists and three that he
raised himself — which is 10 times the average for the species.

 In all, this summer sixteen hand-reared Spoon-billed Sandpiper fledglings and
eight adults were marked with uniquely inscribed plastic leg flags. Birdwatchers
are being asked to report all sightings of Spoon-billed Sandpipers.

Coordinator of the Spoon-billed Sandpiper Task Force, Christoph Zöckler,
said: "The Rudong mudflats are an extremely important stop-over site for the
Spoon-billed Sandpiper to rest and feed and it is very exciting news that our
Russian breeding birds have been sighted there. Unfortunately these mudflats,
like much coastal wetland along the East Asian–Australasian Flyway, are
threatened by the development. Alongside illegal trapping and hunting, it has
pushed these birds to the edge."

 WWT Head of Species Conservation Department, Baz Hughes, said: "This is why
we're taking extreme measures to prevent its extinction: hand-rearing chicks to
boost numbers, but Spoon-billed Sandpipers rely on the help of so many people.
Reports like this are only possible thanks to the support of birdwatchers
throughout Asia and are an invaluable part of its conservation."

Rudong mudflats are the most significant known staging post in China for
Spoon-billed Sandpipers, where 106 individuals were counted last year in
October. Demand for land is high in the region, which is only 150km from
Shanghai, and land has already been reclaimed from the marshes at Dongling to
the southern end.

Pavel Tomkovich of Birds Russia, who caught and marked the bird with Nikolai
Yakushev, said: "When I marked 'Lime 01' I wondered if anybody would ever see it
on its travels, almost a quarter of the way round the world, as looking for
Spoon-billed Sandpipers can be like looking for a needle in a haystack. Looking
for marked birds is even more difficult as we were only able to mark eight adult
birds with these unique flags. Thanks to the reports of local birdwatchers,
we're learning their stopover points."

 'Lime 01' was seen leaving the breeding grounds on 4th August and was seen
5,000km away at Rudong on 31st August. Spoon-billed Sandpipers can cover as much
as 1,000km per day, leaving around three weeks during which it may have been
staging elsewhere

BTO Head of Projects, Nigel Clark, said: "We've known for a few years that
they stop at Rudong mudflats and we hope to be able to protect it. But our
calculations indicate that 'Lime 01' probably stopped somewhere else for up to
three weeks before reaching Rudong. We want to find out where that is in case it
is under threat."

 Zhang Lin of the "Spoon-billed Sandpiper in China" Team said: "The first
Spoon-billed Sandpiper arrived at Rudong about two weeks ago since when I have
been regularly scanning the increasing numbers of waders at the high-tide roost
at Rudong. When I glimpsed a bird on 31st August that looked like it had a lime
green leg flag I knew something exciting was in front of me. On closer
inspection it turned out to be 'Lime 01'. I was over the moon as this is the
first time that one of the birds marked in 2013 has been seen in China. It is
amazing to see how these little but critically endangered birds are connecting
our key sites along the flyway between Russia and China. They are very important
as they allow us to track whether efforts to save the species are working."

 Guidance on reporting Spoon-billed Sandpiper sightings is available from the
East-Asian Australasian Flyway Partnership Spoon-billed Sandpiper Task Force www.eaaflyway.net/spoon-billed-sandpiper.php. To
follow the progress of the Spoon-billed Sandpiper conservation breeding
programme visit www.saving-spoon-billed-sandpiper.com.

The safety tens of thousands of swans and geese in the UK could be improved by new research into collisions with power lines, which started this week with the installation of more than 150 special bird diverters in Lancashire.

Flying collisions are the most commonly recorded cause of death for swans, whose size means they have poor manoeuvrability in flight. Bird diverters are special attachments to the lines that help make them stand out to birds in flight. For the first time, a partnership between Electricity North West, Lancaster University and the Wildfowl & Wetlands Trust (WWT) is studying the efficiency of different types of diverter, alongside agricultural, weather and landscape factors that affect birds' flights. The study area around WWT Martin Mere in Lancashire is the winter home of 30,000 Pink-footed Geese and 2,500 Whooper Swans and has been identified as a sensitive area for collisions.
Dr Eileen Rees, Head of UK Waterbird Conservation for WWT, said: "Tens of thousands of migratory geese and swans make the UK's wetlands their winter homes. Collisions with power lines are a major cause of death for them, so WWT is delighted to be working with Electricity North West to make Lancashire, and the UK as a whole, a safer place for them. Through this innovative partnership we aim to gather evidence for solutions that work in our modern landscape. As well as reducing the risk to swans and geese, the results of the study should help electricity suppliers throughout the UK provide their service with fewer unnecessary interruptions."

Steve Cox, future network manager for Electricity North West, added: "We hope that the diverters and our subsequent research will go on to help birds and electricity customers across the UK. By working closely with WWT Martin Mere we discovered this was a sensitive section of the network as it was located in a known flight path and we are delighted to be able to help protect these wonderful birds. By limiting the chances of any collisions, the special diverters will also reduce any possible impact on customer power supplies."

Dr Ian Hartley, a Senior Lecturer at the Lancaster Environment Centre at Lancaster University and a behavioural ecology expert, commented: "This is a great opportunity and we are very pleased to be working with new partners on a project of such high calibre which is going to have a large impact on the area around where the geese and swans winter. One of our Master's students will work on the project for a year and our input will be to add knowledge on the analysis and geographic information systems aspects."

Throughout this winter, the study will closely observe the flight behaviour of geese and swans in and around WWT Martin Mere Wetland Centre. It will determine the importance of features such as tree lines, the choice of crops and the wind direction on the birds' choice of flight line and height.

For more information about Electricity North West please visit www.enwl.co.uk, and for further information about WWT see www.wwt.org.uk.

Last week's extraordinary tale regarding the Hebridean White-throated Needletail (recounted here) drew plenty of positive response from readers, particularly those who had been lucky enough to connect with one of the few previous occurrences of this exhilarating central Asian species. Of those, the 1984 Shetland (Hillwell, 25th May — 6th June) and 1988 Orkney (Hoy, 28th May — 8th June) were the most 'available' to twitchers. Here, Nigel Wheatley and Mike Cartwright share their own experiences surrounding each bird. Firstly, Nigel takes up the story on 2nd June 1988:

"The epic news was relayed by Alun Hatfield, early Thursday morning. He then spent the whole day on the phone making sure the team had places on the ferry to Hoy. Well behind schedule, Al, Tony Clarke and Robin Chittenden (all from London) picked me up at 10:30pm near Reading and we headed north, picking up Ian Ricketts on the M6. Worried about the lack of time, we stopped only for fuel and zapped along at a steady ton. At Inverness, we landed on a roundabout and some way north very nearly met our doom when the car refused to round a corner — we only stopped two feet short of a barrier that overlooked a nasty cliff.So, it was with some relief that we finally got out the car at John O'Groats to news of a Pallas's Rosefinch on North Ronaldsay. Absolute pandemonium set in. Eventually it was agreed to try for the swift first, so we boarded the ferry and crossed to Hoy — Tysties, Arctic Terns, Arctic andGreat Skuas, Puffins and a European Storm-petrel were seen en route. Once on Hoy, we were taken to Melsetter House in a fleet of rusty cars and minibuses. Alas, an hour of no joy and the time came for us to make a decision about catching the ferry to North Ronaldsay. Never had I seen so much uncertainty on a twitch, as people ummed and ahed about whether to head for North Ron or not. I could barely afford the cost of getting to Hoy, let alone an extra ferry trip on top, so I remained on Hoy as the other 25 or so rushed off north once more.Back at the mansion, all were asleep in the garden on my return. I went scanning from a nearby lane and, at 5:30pm, suddenly clapped eyes on a tiny black-and-white rocket bombing across the fields — "there it is!". I hurried back to the house to relay the news to everyone only to find the bird already there, swooping in, low, and back out again!

We moved out on to the lane and there it was, the White-throated Needletail — working the flies and bees along the edge of the sycamore stand with unbelievable speed and agility. One slight movement of the wings acted like a turbo switch as it shot high in to the sky. It would occasionally swoop low over the field, giving supreme views of its coppery-edged silver mantle in the sunlight, but spent most of the time working up and down the garden edge — the chocolate belly, white 'arrow' and forehead all observed well as it turned just a few feet away, frequently sweeping past our heads with a 'whoosh'! With many of the 'tickers' heading off, just five of us were left to enjoy the bird until 9pm when, after three unsuccessful attempts to land on the building, it disappeared. We retired to the local hostelry for some much-needed food before returning to the mansion, where the very friendly owners let us sleep in their summer house.The Liverpool crew departed early on the Saturday, leaving me alone with the swift on this beautiful island. I enjoyed it for much of the morning until, just as I was about to tuck in to some surprise sandwiches and coffee brought out to me by the mansion owners, the Rosefinch twitchers reappeared. I said, "follow me", and we all ran down the lane — they soon gave a great roar of approval as the bird made its first pass over their heads at the garden edge.
Nigel's excellent sketches of the Hoy Needletail (Artwork: Nigel Wheatley).

The Needletail went straight to the top of many people's list of British favourites (mine included) for it was an aerial delight — a "flying Killer Whale" according to one observer. We happily returned to John O'Groats and drove merrily home to a welcome bed, bath and larder. It was, in short, an epic encounter."The Pallas's Rosefinch Nigel mentions was never accepted on to Category A of the British list. Nigel added that, shortly after the swift, he (among others) headed down to Clevedon to see a Black-winged Pratincole on 12th June before, on 3rd July, they were on Anglesey for a Bridled Tern at Cemlyn. Coincidentally, both species have been recorded in Britain in the week following the Harris bird..!

Four years before the famous Hoy Needletail, what could potentially have been the same bird spent almost two weeks in the Hillwell and Quendale area of Shetland. This was a time long before any sort of bird news information service existed, and as such Mike Cartwright had no idea of the presence of the bird as he began the long trip north to spend a week on Fair Isle. Mike takes up the narrative:

"My story starts on 28th May 1984. Having travelled to Aberdeen by train and boarded the St. Claire for Shetland, I was full excitement for what might unfold in the coming week that I had booked to be on Fair Isle. Nobody on my limited 'grapevine' had of any news from Shetland, and of course there were no news services back then, either. As we left Aberdeen I stood at the back of the boat with two other birders watching a glorious evening unfold, though there was little in the way of seabirds.We immediately got chatting. They were having a birding holiday on Shetland, hoping to see theBlack-browed Albatross at Hermaness and the four female Snowy Owls on Fetlar among other things. Although I had seen these before I felt envious of them; what if I went all the way to Fair Isle and saw nothing?! They were envious of me, though, and suggested I might see something amazing like a Cretzschmar's Bunting!Having started to talk about rarities, they then told me about a conversation they had with Bobby Tulloch the previous day: a couple of days previously, Needle-tailed Swift had been seen and photographed by Dennis Coutts while he was supposed to be photographing a wedding at Loch of Hillwell, but they had had no further news since. We all stood in awe, contemplating the bird and then had a laugh at what the wedding photographs must have been like — assuming there were any!We reasoned that this highly mobile species would have long since departed — as swifts tend to do — but hoped there might be something else found up there. Never having heard of Loch of Hillwell and assuming it to be north of Lerwick, I was surprised to hear it was at the south end of Mainland. I needed to get to Grutness — at the southern tip — to catch the Good Shepherd to Fair Isle. A plan was hatched: they would very kindly give me lift and we would have a look at the loch, even if it was simply to pay our respects to this amazing bird rather than hope to actually see it. After all, that was too much to hope for given that there had been no news for a couple of days.After docking the following morning, we journeyed south in a small, blue hatchback. I was in the back, completely submerged by luggage and rucksacks and surrounded by condensation-covered windows. Eventually we were driving along the north side of the loch, and I wiped a small hole in the condensation to reveal the outside world: there were some hirundines but then, as we bumped along further, I caught a glimpse of a huge pale-backed swift that was moving very fast. Disbelief...no, it really is! Panic!"It's here! It's here!"The car jolted to a stop. I tried to get out — there were only three doors; I couldn't."Where?"I couldn't see for mist, lack of space and sheer excitement."I need to get out...get out!"At which point it zoomed back past me."It's there!"From outside it must have looked hilarious as the three of us and various bags exploded from the poor little car. But no mistaking it, there was the Needletail, putting on the most exhilarating of displays and to just the three of us! Its stunning speed and beautiful markings — the wonderful greenish sheen to its upperparts, the huge white undertail and chin offset by dark brown — were just incredible. I don't know how long we watched it for — I sort of slipped into another dimension; I think it was for a good few minutes, but equally it could have been seconds or weeks. We were all captivated, in awe and totally numb. It gradually started to make each pass a little higher and when it eventually departed to the northwest I knew that this was an experience that would never be repeated.

At the time, of course, we had no idea that it had been faithful to this spot. We looked at each other, the abandoned luggage and car. The incredible realisation of what we had seen cut through the peace of the loch; we were stunned. It was some minutes later, as we re-engaged with an Earthly time zone and the beautiful loch now calm but somehow incomplete without its spectacular guest, that we realised that a Corncrake was calling on the other side and probably had been doing so the whole time!Even to this day this is still the rarity that I have had the most luck with. It would have been so easy not to have seen it in the short time I had available. In fact, I could easily have never known about it. This finally dawned on me when the Good Shepherd docked on Fair Isle and I was met by Nick Riddiford, who wasn't able to leave the island and had the most agonised look on his face. "Do you know about the Swift?"That afternoon was spent on top of the cliffs looking down into one of the geos and watching aSubalpine Warbler among the Thrift and Sea Campion in exquisite light, ending a truly memorable day. Nearly thirty years on, the Needletail remains one of my most treasured memories — though the memory had dimmed over time, the events of last week totally reignited my own recollections. It could have been yesterday!"

Nigel Wheatley & Mike Cartwright
Friday 5th July 2013

The British Trust for Ornithology (BTO) hopes to answer one of British ornithology's greatest mysteries using the very latest that technology has to offer in a project starting this summer. The House Martin is well known to many people; from April to September it lives cheek by jowl with those lucky enough to have this energetic little bird nest under their eaves. In recent years, however, the number breeding here in the UK has fallen by two thirds, leading to the species being Amber-listed as a bird of conservation concern and in need of help.

Though we know a lot about the breeding ecology of the House Martin in the UK, once September arrives and this enigmatic bird heads off south for the winter it virtually disappears from our radar. It is not known where in Africa House Martins winter, or how precisely they get there. If ornithologists are to start understanding what is driving the decline of the martins, then it is these questions that will need to be answered.

This summer, the BTO aims to use the latest technology to discover the routes that House Martins take to Africa and to find out exactly where they spend the winter months. BTO researchers plan to do this by fitting a tiny (shirt button-sized) device known as a geolocator to each bird. Weighing less than a gramme, the device contains a clock, a calendar and a light sensor, together with enough memory to store all of the data collected from the day it is fitted until the day it is retrieved.

By comparing daylight length, as measured by the light sensor, with the time and date recorded, scientists at the BTO are able to determine where on the planet the device was at any given time. This information will then reveal the wintering areas, together with the location of possible stopover and refuelling sites, precise migration routes and the timing of the migration through Europe and Africa.

Paul Stancliffe of the BTO commented, "I have long dreamed of being able to follow a bird like the House Martin on its migration from Britain to Africa, to get a glimpse of the places it is passing through and the places that it chooses to stay and rest for a while before continuing on its journey. It is very exciting to think that we are on the brink of new discoveries that should help these delightful birds and provide them with a more optimistic future. This technology comes at a price and we need help to secure enough of them to make the project worthwhile. Anyone interested in seeing how they might be able to help can find out more by visiting www.bto.org. Each device costs £170 and we hope to be able to fit them to at least 20 birds. We need help to support the scientists developing this project."

For more information please visit http://www.bto.org/volunteer-surveys/house-martin-survey/movements.

A remarkable new study, published in the Dutch ornithological journal Ardea, has revealed that Arctic Terns breeding in the northern part of The Netherlands are following previously unknown routes to their wintering grounds in the Antarctic. Seven terns were fitted with geolocators in 2011 and all the birds were recaptured in 2012; of the five devices that gave information, it was revealed that two individuals had passed the southern Australian coastline and one individual had even reached New Zealand before returning to the Southern Ocean! The abstract of the study can be read below:

"Arctic Terns Sterna paradisaea have an exceptionally long distance migration, annually travelling back and forth between the Arctic and the Antarctic. Birds from Greenland, Iceland and the USA were recently found to spend most of the non-breeding period in the Weddell Sea, a small part of the large Antarctic range of Arctic Terns. Based on ring recoveries and sightings of West European Arctic Terns in the Indian Ocean and Australian waters, we expected that terns from The Netherlands (the southern limit of the breeding range) inhabit different Antarctic regions during the non-breeding season to their conspecifics from Greenland. To find out, geolocators were deployed on seven Arctic Terns captured on the nest in 2011 in The Netherlands. All birds were recaptured in 2012 and five devices yielded information on migration routes. The tracked terns spent on average 273 ± 7 days away from The Netherlands, and visited known staging areas in the North Atlantic and the Benguela Current, on both the outward and return journey. Similar tracks were observed in the terns from Greenland. However, hereafter the terns from The Netherlands moved to a previously unknown staging area in the central Indian Ocean, between 20–40°N and 65–100°E, and spent most of the non-breeding season in the Southern Ocean between 35–150°E. One bird migrated as far as New Zealand. Eventually, all five birds spent the Austral summer in Wilkes Land, Antarctica, before flying back to the breeding colonies with a small detour to the same North Atlantic staging area they visited on their southward migration. The total travel distance in the course of the non-breeding period was ~90,000 ± 2000 km, which substantially exceeds previous estimates for this species. Our study revealed new offshore staging areas and a yet unknown route through three different oceans, the longest bird migration described thus far."

The full study can be accessed online here.

Fijn R.C., Hiemstra D., Phillips R.A. & van der Winden J.
Thursday 30th May 2013

Migratory waterbirds have shifted their wintering areas northeastwards due to climate change in Europe, according to a group of scientists including Richard Hearn of the Wildfowl & Wetlands Trust (WWT). Their new study, published in Global Change Biology, found a strong link between changes in the numbers of Goldeneye, Tufted Duck and Goosander wintering across northern Europe and changes in temperature in early winter.

In Finland and Sweden, the midwinter numbers of these three species are more than 130,000 individuals higher than three decades ago. Correspondingly, on the southern edge of the distribution in France, Ireland and Switzerland, numbers have dropped by nearly 120,000 individuals. In several southern countries wintering numbers have halved. Richard Hearn, WWT's Head of Species Monitoring and a contributor to the study, said: "Our world is changing rapidly and conservation tools need to be flexible so they can respond to that challenge. This means more monitoring, to keep track of bird populations that are, in some cases, changing exponentially. It also means maintaining a coherent network of protected areas throughout Europe, and altering their management in response to the changing mix of wildlife that uses them. Studies like this are critical to making governments aware of their shifting responsibilities and helping them plan for the future."

Aleksi Lehikoinen, Curator at the Finnish Museum of Natural History and lead author of the study, said: "In Finland, the change has been strongest in Tufted Ducks and Goldeneyes, whose numbers have increased tenfold. Waterbird numbers are connected with the early winter temperature, which in south Finland increased by about 3.8°C between 1980 and 2010."

This may in turn have implications for their conservation, because birds are making less use of the protected areas that were designated to protect them. The shifts in the birds' ranges may also affect the impact of hunting, as possibilities increase in the north and decrease them in the south, altering potential bag sizes. The research is based on counts from the International Waterbird Census and the results have been published in Global Change Biology.