Icons of Migration – How White Storks Have Inspired the Study of Migration for Centuries

Even in a place so packed full of natural migratory wonder as The Straits of Gibraltar, there are few sights as wow-inducing as a flock of hundreds – if not thousands – of migrating White Storks.  As they move along the coast in huge, glittering black and white columns, tracing the patterns of the thermals they ride, they really are the epitome of visible migration!

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White Storks heading to Africa – July 2020 © Inglorious Bustards

These flamboyant voyagers capture the imagination and curiosity, and have been inspiring research into migration for hundreds of years.  Back in 1822, a White Stork turned up in the German village of Klütz with what was clearly an exotic spear lodged through its neck.  It turned out to be from central Africa.  At a time when it was still commonly believed that Barn Swallows spent the winter hibernating in the bottom of muddy ponds, this Pfeilstorch – ‘Arrow Stork’ – opened our eyes to the possibility of incredible avian journeys, and migration science was born!

Their great size, conspicuous presence and predictable return to nest sites makes White Storks fantastic candidates for study, and extensive ringing (banding) programmes were already underway as early as 1906.  From then until the onset of the Second World War, about 100,000 mainly juvenile birds were ringed, resulting in over 2,000 long-distance recoveries of birds reported between 1908 and 1954.  To this day, this wealth of information is arguably the foundation of what we know about where they travel and the routes they take.

White Storks breed extensively across Europe.  Almost like a watershed, there is a line that runs right through the middle of Germany, along which the westward-flyers separate from the eastward-flyers.  The eastern route leads over the Balkans, the Gulf of Iskenderun, the countries of the Middle East over to East, Central and South Africa.  The White Storks we see here, crossing over The Straits in such spectacular fashion have come from west of that line, their migration leading them down through France and the Iberian Peninsula to concentrate at this point.

For a bird with such a large wing span, flapping flight uses around 23 times more energy than gliding.  Since there are no thermals over the sea, they are driven to seek out the very shortest distance between land masses.  That means that, in an average autumn season, 150,000 White Storks of all ages – pretty much the entire western European population – are pushed towards this one point, looking for their moment to cross the 14 km (9 miles) of sea to Africa.  This gives rise to the spectacle of these huge gatherings, spiralling upwards on rising warm air until they emerge up to 1500 m above the ground and then gliding out into the blue.

From here they continue their journey south into Morocco, across the Sahara and down to their wintering grounds in central Africa.  In fact, having cheered them on in The Straits, we often get to see them again when we travel to The Gambia each December!

In the 90’s came satellite-tagging technology, a new way of gathering information about birds that was set to change the way we understand so many things.  Technology tends to be larger when new and unrefined – some of the earliest tags were the size of a brick!  Since a tag is required to be below 3% of a bird’s bodyweight to avoid hindering it, these gigantic nomads with their fascinating journeys presented the ideal species to take this new toy out for a spin!

This opened up the opportunity to study a whole new world of detail not just about migratory routes, but about migratory behaviour.  White Storks usually migrate in mixed groups of both adults and younger birds.  A number of studies have followed the fortunes of young Storks making their first migration without adults to follow, in order to look at the innate-ness – or not – of the journey plan.

Although their in-born sense of direction takes them vaguely in a south-westerly direction, if displaced by weather conditions they are unable to orientate themselves with any precision and many never fully migrate.  This is very different to small passerines, which migrate more-or-less alone, often by night, following an inherited map and with no guidance from adults.

The high importance of this social inheritance makes a great deal of sense.  As a day-flying, soaring bird, the efficiency of their route is heavily reliant on thermals generated by local topography.  They follow adults to learn an exact route – a kind of thermal highway – which on future travels they will be able to recognise visually and be sure of the optimum journey.

Tags also give us more information on the temporal nature of migration in these birds.  It turns out they treat it rather like a nine-to-five, flying for around 8-10 hours every day when the air is warmest, before resting until the following morning.  They barely take a day off, covering the 4,000 km (2,700 mile) journey from northern breeding grounds to sub-saharan Africa in two to three weeks.  Rather than feeding up before migration like some birds, Storks evidently snack en route only to meet their immediate needs, and lose weight on the journey.  Presumably when you’re reliant on literally being lighter than air, every invertebrate over-indulgence counts!

As satellite tags become lighter, cheaper and more precise, the insights they give us become ever-more fascinating.  In 2018 a project set out to explore how White Storks navigate thermals as a group by analysing individual high-resolution GPS trajectories of individual Storks during circling events.

A thermal is a complex, drifting, constantly changing column of air.  To thermal efficiently, birds need to adjust their flight speed and circling radius to find, and remain close to, the centre of the thermal where updraft is highest. Thanks to the precision of the data obtained from the tags, we are able to see that Storks navigate the thermal based not only on their own perception of the airflow in their immediate surroundings, but also on a complex series of social interactions, reacting to the movement changes of Storks within their nearby subgroup, as well as the leaders of the group at the highest vertical point in the thermal.

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Collective flight trajectories and synchronization in circling direction. (a),(b) Flock trajectories of migrating storks showing different flight types (circling and gliding). Grey arrows show flight direction. Tracks are colour-coded based on horizontal path curvature. The thermal is drifting with the wind resulting in distorted trajectories even if the bird flies in a perfect circle relative to the moving air (c) Curvature against time for each individual. Arrows at the top depict time delays between switches relative to first individual. (d) Horizontal trajectories of birds that switched their circling direction.

How amazing to think that each Stork is effectively acting as an individual sensor, such that the whole flock becomes a distributed sensory array.  In this way, they explore and gather information on the thermal as a group, effectively mapping its structure and enabling them to use the optimal airflow within it.

From solving ancient mysteries to changing our perception of collective movement, to simply turning a good day into an amazing one, these really are inspirational birds.  And they are pouring over our heads at the moment here in The Straits!  We’re thrilled to be assisting as always our conservation partners, Fundación Migres, with the annual autumn migration count – to date over 38,000 of them have made the crossing, and we look forward to many more inspirational moments in coming weeks!

Get some migration inspiration in your life!  Get in touch for day trips or bespoke tours this autumn, or give yourself a trip to look forward to, taking in Migration and Cetaceans in 2021 or beyond…

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The group reach optimal height and reach for Africa © Inglorious Bustards

 

 

 

 

Safe travel to The Straits is back!

As COVID-19 remains under control in Spain and cases continue to dwindle, we are extremely pleased that we can now begin to safely deliver our day trips and tours!  With the announcement of Europe-wide “air bridges” on 4 July, international travel to Spain from many countries is now available with stringent health precautions en route but no self-quarantine measures at either end of the trip.

This spring in The Straits of Gibraltar, one of the world’s most breath-taking migratory spectacles passed by almost unobserved.  But whilst we were all sequestered away, Nature carried on regardless, and now these same birds that passed by so spectacularly unseen are preparing to make their journey to their sub-Saharan wintering grounds, new offspring in tow!

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Honey Buzzard © Inglorious Bustards

We’re thrilled that, this autumn, we’ll be able bring you right to your front row seats at Nature’s greatest show either for a day or bespoke trip, or as part of a scheduled departure tour.

The Strait of Gibraltar is the point at which Africa and Europe are at their closest, and is the epicentre for one of the world’s most spectacular bird migrations.  Every year, millions of birds make the 14 km sea crossing, making use of uplifts and thermals rising off the Rock of Gibraltar and the stunning Moroccan peak of Jebel Musa. An estimated 300,000 raptors and other soaring birds pass over this rugged terrain during autumn, as well as untold thousands of other journeying passerines and seabirds.

As well as the star attraction, a boat trip into the Straits itself will let you get close and personal with our resident cetacean species – Common, Bottlenose and Striped Dolphins and Long-finned Pilot Whale.  Even migrating Fin, Sperm Whales and Orca are possible here.

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Long-finned Pilot Whale © Inglorious Bustards

There’s plenty more to explore among the area’s superb habitats, which include salt pans, intertidal areas, freshwater wetlands, low intensity farmland, Mediterranean scrub, precipitous rock faces and the woodlands of Los Alcornocales Natural Park, Europe’s largest Cork Oak forest.  The diversity and wealth of avian and other wildlife in this beautifully unspoilt area of Spain really is astounding!

Couple this with tranquil accommodation in an eco-lodge at the edge of the Natural Park itself, the chance to enjoy the picturesque streets and Moorish fortifications of the Old Town of Tarifa, and of course the chance to sample some of Andalucía’s best local sustainably-produced food and wine, and you really do have a trip that’s Strait-up fantastic!

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Short-toed Eagle © Inglorious Bustards

We can’t stress enough that the health and safety of our clients and avoiding the spread of coronavirus in wider society have been and always will be our top priorities.  We are proud to have been awarded a badge of approval for our COVID-19 Risk Prevention Protocol from both the Spanish Ministry for Industry, Commerce & Tourism, and by the local Junta de Andalucía for both tourism and “active tourism” specifically.Guía Visual Por Un Turismo Seguro con SARS-CoV2

 

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These badges mean you can book with confidence that we are fully compliant with official guidance set out by these organisations, and have in place a stringent COVID-19 Risk Prevention Protocol.

Additionally, we receive training and take advice from our independent risk prevention consultants, Quirón Prevención.

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Upon booking and arrival, you will receive a comprehensive guide on measures taken and your own responsibilities.  Here’s a summary of the measures we’re currently taking to protect you and others, which we´ll update periodically:

  • When we meet you, we’ll go over our COVID-19 Risk Prevention Protocol in detail, and introduce you to the whereabouts of hand-sanitiser and thermometer. Sadly, there’ll be no hugging!
  • You can expect our minibus to have been thoroughly cleaned using recommended virucidal products before the start of the trip, and at the end of each day, and to display clear signage about hygiene, self-protection and distance guidelines.
  • We ourselves will also be thoroughly scrubbed and wearing clean clothes that have been washed at >60ºC.
  • Only two seats per row in the minibus will be occupied, meaning you’ll be sharing with a maximum of five other people. Wearing of facemasks will be mandatory during journeys.  You’ll always have the same seat.
  • If you have your own vehicle, you may use it to follow us if you’d prefer.
  • Thanks to the nature of our passion, we’ll be mostly outside and away from crowds! Group sizes will be also be small. In the event that we can’t maintain appropriate social distance, facemasks will be worn.
  • We’ll encourage you to bring your own protective masks and hand sanitiser for frequent use, but we’ll always have a stock of these available for your use.
  • We’ll encourage you to bring your own optical equipment and not share this. We can however still lend out disinfected binoculars for your personal use during the trip.  Although we cannot share scopes, we have digi-scoping equipment that will allow you to see without coming into contact with the scope.  As always, we will have field guides with us, which we can show.
  • We have stringent procedures in place should anyone – including us – fall ill during the trip.
  • Any accommodation used or hostelry establishments visited are known and trusted, and verified to also have a COVID-19 Risk Prevention Protocol in place.
  • Our legendary picnic lunch will be provided as usual – hygienically prepared, served on disinfected reusable crockery to avoid plastic waste and stuffed full of locally sourced, sustainably produced and delicious ingredients!

We are also keeping a close eye on international travel advice from the World Health Organisation, Spanish government and relevant Foreign Offices.

We hope that with everyone’s collaboration this situation will continue to improve and we will see you soon in The Straits and beyond to enjoy the best of #FlywayBirding.

We still have limited availability remaining on our Straits of Gibraltar – Bird Migration & Cetaceans scheduled departure tour, 26th August – 1st September 2020.  We also have selected availability for day tours or bespoke trips throughout the Autumn migration season!  We are happy to take no-financial-obligation provisional bookings for future tours – just contact us to register your interest and talk further.

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Black Kite © Inglorious Bustards

 

Fourteen Kilometres of Joy and Sorrow

Travel Blogger of the Year

Read our award-winning blog about how a sudden drop in the wind on an autumn day in Andalucía inspires heart-stoppingly spectacular mass avian movement, but also provokes thought on travel, conservation and global change…

 

 

Fourteen kilometres of sea and sky are all that separate two continents. At 9am, the Mediterranean sun is already warming the air and sparkling on the calm waters. It’s early autumn, and this narrow – but potentially deadly – stretch of sea is all that stands between countless millions of birds and the next leg of their journey to African wintering grounds.

It’s been windy all week in The Strait of Gibraltar, making the crossing too dangerous for larger birds. Without the help of uplifting coastal air currents, they must power all the way, or face drowning. They’ve been stranded in the avian departure lounge for days and they’re hungry and desperate to continue their journey.

As mid-morning arrives, thermals form over the rocky coastline, and they’re finally cleared for take-off! In minutes, the sky fills with birds of prey. Eagles, Kites, Harriers and Honey Buzzards, swirl together in almost incomprehensible numbers and barge south along the suddenly congested flyway.

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juvenile Black Kite © Inglorious Bustards

Chirpy European Bee-eaters pass over in vocal family groups, fifty at a time, quipping and chatting excitedly like they’re off on holiday. Clouds of thousands of White Storks form, sparkling black-and-white as the flock circles around on itself, turning the air currents to art.

The incredible spectacle continues all day, ending with streams of late arrivals racing over in their hundreds, seemingly experiencing `flyway rage´, desperate to reach Africa before sundown.

This breath-taking migratory marvel is beyond compare! During one rapturous, raptor-filled day at Spain’s most southerly point, I’ve counted over 20,000 soaring birds making the commute to the northern coast of Morocco – a mere fraction of the 450,000 that will pass through here in a season. 

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Migrating White Storks © Inglorious Bustards

Imagine looking up from your tapas in Tarifa town and seeing layers upon layers of birds gliding overhead, stretching as far as the eyes can see in every direction, including ‘up’. It’s not surprising that this experience has the power to reduce many folk to tears! 

But it also has the power to provoke thought, about travel, conservation and global change.  With so much at stake, how do we help these feathered wanderers fulfil the yearly promise of return?  Must the joy of watching wildlife inevitably encourage consumption of the planet’s resources? How can our passion for travel and wildlife be channelled into a positive outcome for the environment?  How can we turn “eco-tourism” into a promise, rather than an oxymoron?

Even in the face of a global pandemic, we must not forget that climate change is still the biggest emergency facing our planet and the biggest threat to our survival, and that of so many other species. But it is easy to condemn travel, while conveniently ignoring agriculture and spiralling consumerism as major contributors to the emissions that cause global warming.

For many species, habitat loss, intensive agriculture and localised threats are the immediate emergency. Without travel, protected areas lose their economic value and habitats are forgotten. The voice to protect them inevitably becomes drowned out as they become meaningless to most, something you can only see on telly.

Without travel, we lose support for countless local conservation organisations, community businesses, and sustainable ecotourism endeavours, working hard to effect change at grassroots level. So too we lose understanding of our connection to the habitats, landscapes and cultures that Nature’s nomads pass through. 

From a conservation standpoint, the concept of saving species across flyways is an important one. After all, there’s no point fixing things for a wandering bird in its breeding grounds alone without giving it a helping hand across its entire migratory range. Places like The Strait of Gibraltar are rare, not just for their importance and natural beauty, but for their power to open people’s minds to migration and the interconnectedness of things.

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A view across The Straits © Inglorious Bustards

By the end of November most of the birds of prey have passed through, and the skies of my home seem a little empty. But winter in The Strait brings its own visitors. Northerners seeking a bit of winter sun arrive in their thousands. Cranes fly in raggedly lines over the rice fields, bugling to one another. Tiny Chiff-chaffs and Blackcaps scuttle around the wild olive trees, waiting for the lengthening days to carry them back north.

Then one day in February conditions are suddenly right, and the first arrivals of spring are coming! Huge columns of Black Kites will be visible surging from the northern coast of Morocco, as if someone has popped open a bottle of champagne. Seemingly within minutes they’re arriving to the clifftops above Tarifa – my ringside seat for this migratory dance!

They have travelled from the moist forests of Africa, across the Sahelian scrublands and the Sahara, over temples, mosques and churches. They have overcome unstable and ever-widening deserts, persecution, pollution, habitat loss, and finally crossed this mere fourteen kilometres of sea and sky at the meeting of two continents. For me there is no bigger joy than a promise of return fulfilled.

Inspired by the brief to write about “My Favourite Place On Earth”, this blog first appeared under the title “Fourteen Kilometres Between Two Continents – 450,000 Soaring Birds Can’t Be Wrong!“, as part of Terra Incognita’s Travel Blogger of the Year 2020 competition.  It was placed in the Top 10 out of over 150 entries, by a panel of 20 judges including world-renowned travel bloggers, writers, conservationists and ethical organisations.

Maybe you´d like to experience the joy and sorrow for yourself?  Look no further than our migration tours and give yourself something to look forward to…

Braving the Blades & the work of Fundación Migres

We all know that turbines and soaring birds don’t mix. So what is being done to help our avian nomads as they pass these whirring legions marching across the Estrecho Natural Park, one of the most important raptor migration bottlenecks in the world?  We report on the Compensatory Measures Project, just one strand of the immensely important work carried out by our conservation partners, Fundación Migres.

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Griffon Vulture surveys The Straits © Inglorious Bustards

As we round the corner of the coast road, in the hills high above Tarifa, most of our tour groups let out a gasp of awe at the stunning views of Morocco. This is often closely followed by a gasp of shock, as their gaze falls on the imposing ranks of wind turbines lining some of the coastal hillsides. 

At just nine miles wide, here the Strait of Gibraltar is at its narrowest point between Europe and Africa, making it the chosen crossing point for over 300 million migratory birds, journeying between these continents twice a year.

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Monitoring the Straits © Inglorious Bustards

A humungous sixty percent of Europe’s raptor population passes through here, as well as virtually its entire population of White Storks. Swifts also cross here in staggering numbers, with more than 400,000 passing through the area during peak times. This migratory spectacle is one of the most uplifting, life-affirming natural events we have ever seen, and simply has to be experienced to be believed.

With some 350 different species recorded, the list of birds in the area is extensive. At migration times there are Honey Buzzards, Western Ospreys, Red-rumped and Barn Swallows, Sand and House Martins, Pallid, Common and Alpine Swifts, Common and Great Spotted Cuckoos, races of Yellow Wagtail, Western Bonelli’s Warblers, Common and Iberian Chiffchaffs, Golden Orioles and Turtle Doves amongst many others.

At any time of year, birds in the area include Crag Martins, Blue Rock Thrushes, Crested and Thekla Larks, Lesser Kestrels, Tawny, Little and sometimes Eagle Owls. A wide range of nesting raptors, including Bonelli’s Eagles, Short-toed Eagles, Common Kestrels and Peregrine Falcons are common in the area. Around Tarifa there are colonies of Griffon and Egyptian vultures, the most southerly in the Iberian peninsula, with 70+ pairs of Griffon Vultures and six pairs of Egyptian Vultures breeding in 2017.

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An Egyptian Vulture checks in © Inglorious Bustards

So how did these feathered millions end up running the gauntlet of the wind farms, adding to the perils they already face?

Back in 1993, when the area was still military land, the original two windfarms were commissioned, approved and built. The 20 MW Planta Eólica del Sur (PESUR) project and the 10 MW Energía Eólica del Estrecho (EEE) farm totalled 269 turbines. They were straight away mired in controversy, with local conservation groups and independent experts presenting evidence in 1994 of high avian death tolls(1). The corpses of 13 different species were allegedly found at the wind farms, either killed on impact or by electrocution on power cables, including an Eagle Owl, White Storks and Lesser Kestrels.

A random corpse count of Griffon Vultures stood at around 30, with some apparently decapitated by the blades. Counter-claims at the time by the wind company’s managing directors suggested that the yearly death count was never higher than twelve birds in total, and others presented figures as low as two birds.

In some cases it was alleged that no real impact study regarding the birds was ever carried out. It was even alleged that, while risk assessments were carried out based on presence of resident birds, the experts simply ‘forgot’ to account for the hundreds of thousands of migrating soaring birds that pass through twice a year!

Spain had (and still has) an ambitious plan for alternative energy generation, and the Tarifa area was to be its spearhead. Development of a proposed 2000+ turbines in the area were to provide a sizeable chunk of Spain’s 20% renewable energy target by 2020.

One can only imagine what it would have been like to be a fly on the wall in the many meetings that must have taken place, leading up to the declaration of the area as a Natural Park in 2003. With the area now protected, and acknowledged as an Important Bird Area by Birdlife International, extensive study and intensive mitigation work would be needed to reduce the negative effects of existing farms and prevent the creation of new ones in high-risk areas.

Enter Fundación Migres. This private non-profit organisation had been monitoring the area’s extraordinary migration event with daily counts during peak times since 1997.
In 2003, the companies whose memberships form the Tarifa Wind Power Association (AET) signed agreements with Fundación Migres to work on the Compensatory Measures Project for La Janda Windfarms, dramatically expanding their remit.

During the seventeen year project, their task was to find ways to reduce bird mortality in the windfarms, find out the effect of the farms on local raptor populations, and establish recovery programmes for more affected species, as well as raising awareness locally about environmental conservation and renewable energy.

The high-quality, independent science they have generated since their inception has added considerably to the world’s knowledge on wind farms and their effects on birds. It is helping develop better protocols for Environmental Impact Assessments (EIA) and mitigation measures to reduce turbine collisions.

Their work has generated both disturbing and promising results.  A three-year study of 20 operational wind farms took place between 2005 and 2008, as the 323 turbines gradually came online(2). Over the study period, the research team found 596 dead birds – a devastating 1.33 birds per turbine per year, which is among the highest rates of wind farm mortality ever published. 36% of the dead were raptors and included 23 Common Kestrels, 13 Lesser Kestrels and 16 Short-toed Eagles.

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Short-toed Eagle © Inglorious Bustards

By far the worst affected bird was the Griffon Vulture, with 138 found dead during the course of the study. Other studies suggest that most birds of prey can detect and actively avoid turbines without too much problem(3), but alas for the Griffon Vulture, for all its aerial prowess, agility is not one of its strong points. The bird relies on air currents and thermals to travel and has relatively weak flight, making evasive manoeuvres difficult.

All of these high-mortality wind farms had had EIAs carried out according to accepted methodology, had been accepted as low-risk areas, and had been licensed according to the law. The way raptors use the air currents and topography of an area is complex. It seemed site-scale EIAs based on bird abundance did not account for this, so could not adequately predict the threat level of proposed turbines.

However, interestingly, the study also found that the vast majority of these deaths could be attributed to a very small number of turbines. A new study was undertaken(4) – what if, by controlling function of these high-risk turbines, bird mortality could be reduced?

During 2006, body counts on 13 windfarms with 296 turbines had illustrated that most of the deaths were being caused by just ten turbines, distributed amongst six windfarms.

During 2008–2009, the team implemented a selective stopping program – when Vultures were observed near these deadliest turbines they were simply turned off till the threat had passed. Encouragingly, the Vulture mortality rate was reduced by 50% with only these ten turbines involved. The consequent reduction in total energy production for the wind farms was just 0.07% per year, a small price to pay.

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Mega migration White Storks and Black Kites © Inglorious Bustards

This successful strategy was expanded to other high-risk turbines. When a high number of raptors are passing through, or individual birds are in danger – especially Griffon Vultures or the Critically Endangered Egyptian Vulture – the turbines are simply turned off.

With Migres-trained wind farm ‘watchmen’ on high alert, the whole shutdown process – from spotting a risk, to phoning it in, to stopping the relevant turbine – takes less than two minutes. The annual mortality – previously exceeding 200 vultures – has been reduced by 60% across the whole area(4). The accidents happen mostly during the autumn migration period when young birds – both resident and from all over Europe – are passing through the area. Though this is still a horrible price to pay for clean energy, this level of loss is at least thought to be sustainable from a population size point of view.

The process is far from perfect. A locally-breeding Egyptian Vulture was killed by a turbine last year, and two the year before. A drifting radio-tagged Lesser Spotted Eagle also hit a turbine, but seemingly recovered its wits and moved on, after sitting dazed in one spot for two days. We ourselves have been devastated to witness a majestic Honey Buzzard, hanging on an air current, lose control for just a brief second and get sucked backwards into the blades. And this is without even touching on the as yet unmitigated effects the turbines have on bats and other wildlife.

The end of the windfarm cooperation project in 2020 is fast approaching, putting the future of the turbine-stopping measures in doubt. With funding for Fundación Migres in decline, also at stake is one of the greatest sustained efforts for monitoring migratory birds in Europe, not to mention the invaluable research they generate.

It can be hard to believe that wind farm development was ever given the go-ahead in such a key area for the birds of the East Atlantic flyway. But it’s important not to forget the bigger picture. Many more birds are killed by traffic, power lines, radio and television towers, glass windows, and due to human activities such as poisoning and illegal shooting, not to mention habitat destruction.

Badly located as they are, the ever-spinning blades of the Straits supply around 20% of Andalusia’s power. Like all locally-damaging ‘renewable energy’ sources, they are there because of our insatiable appetite for consumption – of fossil fuels, of meat, of stuff we just don’t need. As the planet warms, ecosystems are disrupted and the Sahara creeps ever larger. For the millions of avian nomads that pass the turbines unharmed, the biggest peril is whether they still have breeding and wintering habitat to go to.

Want to get involved? You can help out Fundación Migres by volunteering to be part of their monitoring programmes or donating  – see www.fundacionmigres.org for details.

(1) Watts-Hosmer (1994) Bird deaths prompt rethink on windfarming in Spain. Windpower Monthly
(2) De Lucas et al (2012) Weak relationship between risk assessment studies and recorded mortality in wind farms. Journal of Applied Ecology
(3) De Lucas et al (2004) The effects of a wind farm on birds in a migration point: the Strait of Gibraltar. Biodiversity and Conservation
(4) De Lucas et al (2012) Griffon vulture mortality at wind farms in southern Spain: Distribution of fatalities and active mitigation measures. Biological Conservation