continental drift
by stephen daly
For amateur nature lovers and serious ornithologists alike, the late summer and autumn bird migration is a fantastic spectacle. Every year, when the great migration pathways of the world come alive, The Strait of Gibraltar, one of the busiest routes on the planet, sees a constant flow of bird movement south.
This all takes place right on our doorstep and is without doubt an amazing sight to witness, with huge numbers of birds crossing between southern Europe’s Iberian Peninsula and northern Africa.
Fifteen km's takes only thirty-five minutes by fast ferry from Tarifa
How Many Birds?
It is estimated that in excess of 650,000 birds representing more than 80 species, of which 190,000 raptors will pass over our heads during the autumn migration back to Africa.
By late August each year most of us will have noticed the start of the migration with huge flocks of White Storks and the less common Black Storks spiraling in the clear warm air. This behaviour tells us that something's afoot. Along the rice fields and canal ditches of the ancient lagoon of La Janda, thousands of White Storks feed up on crayfish, frogs and larger insects, converting this all to fat reserves for their precarious sub-Saharan flight. Black Kites arrive from all over southern Europe and feed as best they can on road-kill, snakes, young birds, frogs, in fact they’they will take anything at all that’s edible and remain one of the world’s most opportunistic and enterprising birds of prey with huge “old world” distribution and population.
By the first three weeks in September the migration is in full swing with many other different species moving south, many of these are raptors or birds of prey. Booted Eagle the smallest of our European Eagles and the larger winged Short-toed Eagles are joined by Sparrowhawks, Honey Buzzards and Egyptian Vultures. Griffon Vulture to the most extent, are non-migrants but do tend to follow other birds flying south during this period. This mass movement continues until October.
Changing Patterns
Raptors, more than any other family of birds, exhibit massive, visible, and far-ranging migrations, while their diversity and abundance in many places are critical indicators of the health of our fragile ecosystems. The meeting of the continents of Europe and Africa is a critical global crossroads for the fascinating and interconnected phenomena of bird migration.
Bird behaviour is one indicator of Global warming and our continuous climate change. Man’s actions have a persistent influence on numbers and distribution of all creatures. From our first days as farmer-gatherers, through to the intense industrial agricultural process of the present day, man has constantly and dramatically changed the physical landscape and molded vast wild areas to suit our species. Weather patterns are without doubt changing and just as Man has to adapt to severe drought and equally devastating floods each year, birds too are under immense pressures to adapt and cope the best they can.
Each winter see higher numbers of White Storks as well as Booted Eagles, wintering in Andalucia without the need to source food in warmer Africa. This assuredly is a clear indicator of our uninterrupted and accelerating global warming.
The Journey and the Dangers
Parties of migrant birds tend to stick together, joining up en route and can be seen anywhere on the Atlantic seaboard as well as inland. The birds that travel overland, primarily use natural physical features to navigate, such as valleys and rivers that lead to the coast. Other navigational abilities that are still not fully explained, include navigation by sun and stars, magnetic energy from the Earth and the ability to smell microscopic particles in the air that relate to the area in their wintering destination or conversely their place of birth. But the coast from Cape St Vincent in Portugal right down to Gibraltar has a tremendous amount of migration activity.
Booted Eagles and Honey Buzzards tend to go for the crossing down on The Strait towards Algeciras whereas Egyptian Vultures tend to cross at the shortest point between the two continents close to Tarifa. A great deal depends on what the weather conditions are like when the migrants arrive on the south coast and take the first major hurdle of crossing an open stretch of sea. The wind and sea currents can be treacherous and for birds large and small birds alike and presents an extremely dangerous challenge. Birds leaving Europe during a very strong easterly or Levante cannot tell visually that the wind strength increases in the centre, coupled with the fact that there no thermals over the sea to assist birds. Sheer muscle power, determination and great energy reserves are required under such circumstances. Some migrants inevitable get blown completely off course out into the Atlantic, past Morocco’s Cape Espartel and are unable to make landfall and perish.
Westerly winds known as Poniente are kinder and pose less of a danger.
Watchpoint Locations
Close to the coast, are the main “Migres” migration watch points manned by volunteers each year from the end of July until October, that monitor and record the numbers of birds of prey including the beautiful and much rarer Black Storks passage.
The three main observation posts are all very close to the main N340 (A5) coastal road.
Just east of the town of Tarifa at KM 87 is Tráfico and Cazalla is a little further on at KM 90.7.
Heading east down the coast towards Gibraltar is Algorrobo. This watch-point is stated at KM 99.1, just west of Algeciras.
There are of course lots of other excellent observation points all along the coastal and indeed slightly inland in the Alcornocales fringes or towards Atlanterra and the Sierra de la Plata. Birders without too much experience may tend to hang around the watchpoints to learn raptor identification from more knowledgeable birders. Listen first to those who are calling out the birds as they come over and try and find someone who knows their birds. It may also help to know the Spanish names for some of the commoner birds of prey that are called.
In 2007 work started to build a proper, larger building at Cazalla. This will be hopefully completed ready for the 2008 autumn migration with facilities for the public and volunteers alike. Access from the busy N340 road and parking should be easier - but let's wait and see. The brick hut that was there before was totally inadequate for observers and the public alike and only now are more inroads being made to develop infrastructure relating to birding, wildlife and other outdoor pursuits. There is certainly a reasonable percentage of annual tourism income generated in the area due to the wealth of natural history and scenic beauty of this rich area.
Stephen Daly writes about
the beauty of the annual raptor migration on The Strait of Gibraltar
Another september kicks in with thousands of birds over our house at La Oliva near Barbate in southern Spain. We are on the pathway of one of the busiest mig rational bird routes in the world. Over the last month endless parties of Black Kites have soared, flapped and glided at various altitudes over our heads following the mouthof The Strait of Gibraltar down towards Tarifa and Algeciras, where the Strait narrows and the crossing is lessof a strain on these wonderful creatures.
September and October are just about fully booked for Stephen Knapp and myself, with our planned longer migration birding holidays and day tours. On the 3rd of September, Robin Chittenden and I are co-leading an eight day tour to the Algarve. This tour is organised by Limosa Holidays and The Travelling Naturalist. I co-led last years tour and it went very well indeed with great birds, lovely hotel in Silves, the oldest city in Portugal and of course with superb Algarve weather - A bit of home from home for me really! Stephen K will be holding the fort here on The Strait of Gibraltar until I return.
I've been very busy recently with all kinds of building jobs around our house and have been stopping every few minutes throughout August to check the skies. It's just been stunning so far. Even today as I write, I had two adult Bonelli's Eagles high above the house, above a large flock of Black Kites. Sitting outside eating dinner yesterday evening, a long 'v' shaped line of birds appeared from the west. Right over our heads flew about sixty Glossy Ibis. Our regular Red-necked Nightjar flew right past Patty's head as she got up from the table. We raised our glasses in salute.
Woodchat Shrikes, Turtle Doves, Nightingales and Spotted Flycatchers have been coming and going around our garden. Constant burbling-whistles from flocks of bee-eaters force us to search for them, sometimes easily spotted other times we fail to find them in the bright midday light. It's just been fabulous. Stephen Knapp was surprised when watching his resident Cirl Buntings taking a drink in his garden, a Booted Eagle came from nowhere and landed on one of his wooden fence posts
I hope to spend more time updating the web site with report and photos to show you all. I just hope I can mangae to do this.......... Have a great time out in the fresh air and happy birding
all archived news will be displayed soon
click here for most of the past months to get an overview of what to expect with migration and weather for each month.
Jan 2006
Jan 2007
Feb 2006
Feb 2007
March 2006
March 2007
April 2006 April
April May & June 2007
May 2006
June (A) 2006
June (B) 2006
July 2006
July & August 2007
August 2006
September 2006
October 2006
November 2006
December 2006
December 2007 & January 2008
Raptor Identification Page 2
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