Eagle tango
Across the valley there appeared a huge, dark, shape, hanging over the top of the peak in front of us.
What we were watching was so still, so motionless, that at first I
could hardly believe it was a real bird; no movement of a wing to
keep itself poised in the air, neither advancing or being blown back, a
demonstration of absolute control. We peered through our telescopes, and knew that it was an golden eagle.
Then, just above, was a second silhouette, even larger, so the female eagle, likewise poised above her partner, both so still that we didn’t need to move our telescopes. Were they hunting, scanning the slopes below them for a late catch as the sun was setting? Well, it is a possibility, but what followed next convinces me that more was going on.
We’re at the time of year when the largest birds on the European continent are preparing for next year’s nesting season, amazing as that might seem as winter is only just taking hold. However these birds have months of care before them, intense efforts to bring their single chick successfully into the world, feed and protect it until fledging, and then teach it the skills that it will need to survive and prosper to independence.
Above all, this is a schedule that applies to the bearded vulture (FR Gypaète barbu), but they have large territories, and do not necessarily choose a previous nesting site, so time needs to be spent carefully watching, hoping to find where a resident couple is going to settle. It might be the same site as earlier in the year, but might not be, different factors come into play which the experts sometimes only can guess at, and if a fairly regular watch has not been kept important clues can be missed. Disturbance – often from human activity, mainly accidental – is a major risk; weather conditions too can play a part. These long lived birds need to gain experience, and often are not mature enough to successfully breed in their first decade of life; they too need to find the location that works.
That was the reason why I, with a friend Francine, was sitting on that hill side on a Sunday as the late afternoon light began to fade with the sun setting behind the mountains to the west. It had been a sunny day, and the cliff face opposite us still radiated up warm air thermals; coupled with a slight but steady wind producing ideal flying conditions for big raptors. All combining to give one of the most wonderful avian displays that either of us had ever seen, and it should be said that Francine has been avidly watching birds since she was a young child, and is out nearly every day, watching the skies.
Usually the display flight of a golden eagle is a flamboyant show of mastery of the air; as this, the royalty of birds, demonstrates to potential rivals and its mate a show of power, its dominance of a territory. It will climb high in the air and then, wings folded back, dive down in a series of looping switch backs, sweeping back up again to about the same height; this is called ‘festoon’ in French. I once watched fifteen of these dives, one after another, and it was awe-inspiring to see. It is said that the speeds reached can exceed two hundred kilometres an hour. You have to be lucky to see it.
However, what we were witnessing was very different. Very slowly, the larger bird drifted down to touch the back of her mate with her lowered talons; he dropped a little, twisting to one side, before pulling back up so that the two birds resumed the balanced symetry as before. In the ten minutes we watched she did this three times; it was a dance, a display (FR parade), a delicate, slow tango of gentle intimacy and grace between two of the most magnificent birds in the whole avian world.
Eagles are renowned for the ferocity with which they will defend a territory, they have the stare of a grim warlord, a fearsome beak, massive power in the grasping talons, the enormity of their presence - the wingspan of a female can grow to two metres thirty centimetres. But here we were watching another side of these birds, a tenderness, an intimate moment between a bonded couple. I don’t know if this behaviour has ever been seen by others; but we both felt blessed to witness such a thing, and I will never forget it.
There are plenty of videos on the internet that show the aggressive side of the species, ready to battle with those awesome six centimetre talons (FR serres) over territory and food. Sometimes two eagles will lock talons and spiral down towards the ground, only releasing at the last moment. These birds have little to fear, they are apex predators, but are often harassed by ravens and other corvids who fly behind and mob them as soon as they are spotted. In winter the adults will eat from carcasses on feeding stations, but rarely will give this to the chicks. The other scavengers will give way, but will try to make the eagle’s stay as disturbed as possible – ravens even coming from behind the tail of a feeding eagle and pulling its tail feathers, before leaping prudently away!
Even though the bearded vulture has nearly one metre more wingspan, it does not have the weaponry that makes eagles so formidable. If provoked, however, when close to its nesting site, the Bearded vulture will turn on its rival and drive it away, as the extraordinary photo below shows.
When you find them, golden eagle nests can be huge and impressive. Sometimes used repeatably over many years, at the beginning of each nesting season the two adults will add fresh branches to the existing pile and then line it with scavenged wool to make a soft bed for the precious egg(s). They might have several potential sites in a territory, and will change from year to year, probably to allow the parasites to die off.
It is possible that more than one egg is laid, as 'insurance' if the first does not hatch, and the second may survive, but availability of suitable food can be the crucial element if both chicks are able to fledge. As with other birds, the stronger chick is capable of killing the smaller one in order to monopolise the food supply, but this behaviour - called cainism - is not always that simple. I have once seen two eagle chicks develop and fly the nest in the Aude, but normally there is only one, and the rate of reproduction is not high, but being a long-lived species here the local population is being maintained.
Two Eagles.
She flew, a floating stillness, on the gentle wind-wash of yellow November sunset;
The death talons hanging curled below
Unsheathed blades, trap loaded; Oh I can kill!
Bronze head lowered, the all-seeing eyes arrogant as diamonds on a queen’s hand.
And then there he was, five metres below, the perfect shadow cast
On a transparent screen of wind-slip.
Three times she came to caress the back of her love
He to slide away, a twist of curving ecstasy, the chosen one,
Delighting in the in the intimacy of regal pride
One thousand metres above the world below.
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