It’s not everyday you discover that a tree outside your front gate is a roost for one of the world’s rarest species of bird. ‘Our’ tree was a large acacia growing on wild palm scrub and acacia land in a rural area of Saar.

The first inkling we had of this phenomenon was shortly after we moved into the house when we awoke on a November morning to find four men crouched in the long grass opposite, wielding cameras, tripods and telescopic lenses. Relieved to discover that their lenses weren’t trained on us but on the tree, we wandered out to find out what was happening.

“Shh... don’t disturb the birds,” whispered one twitcher (as bird watchers are commonly known). “We’re watching the Grey Hypocolius take off on their dawn flight.” He indicated the tree which we realised was completely covered in birds, when suddenly a number of them perched on top branches, shot up into the air and in seconds had vanished from view.

For the next ten minutes we were spellbound watching this spectacular avian performance which followed the same pattern over and over again. A new flock of between fifty to one hundred birds would appear from deep within the acacia and assemble on the topmost branches, fluttering and chattering in a distinctive high pitched ‘mewing’ sound which seemed to summon fellow birds from the surrounding palms. At a given signal undetected by us humans, they rose in a cluster, flying high into the wind and disappeared. Their flight was so fast and so high, that it was impossible to follow their route.

The Grey Hypocolius is apparently the only bird of its particular species in the world. It is small, only about eight inches long; the male is dove grey with white and black tipped wings which when spread, reveal a soft pinky/peach underbelly and it has long tail feathers. Its most distinctive feature is a sleek black mask around the eyes rather like the khol blacked eye of a beautiful eastern woman. The female is merely brown/grey with none of the male’s markings.

Its breeding habitats are believed to be in Turkmenistan, Afghanistan and western Baluchistan. It migrates during the winter season between November and April before continuing south into Iran, Saudi Arabia and across the Red Sea to Egypt and sometimes as far afield as Palestine and Oman. Although flocks of Hypocolius have been sighted in these places, for some reason the greatest numbers appear to gather in Bahrain and in particular, around the large acacia tree directly opposite our house in Saar.

The Grey Hypocolius is a very shy bird and rarely spotted due to its mainly inaccessible habitats, so once we realised how privileged we were to be able to monitor the activities of this rare bird from our bedroom window, we became avid twitchers. At dawn, we would pull back the curtains and watch the extraordinary spectacle of the tree come to life from the comfort of our bed, while sipping freshly squeezed orange juice and enjoying a cup of tea.

We don’t know why this large acacia was chosen as the pivotal hub of the Hypocolius, but it became clear that the birds treated this particular scrubland area as a winter roost - and had apparently done so for years. In fact a bird-lover came to visit friends of ours in Bahrain and told them that he was desperate to see the Grey Hypocolius which, according to bird spotting experts, could only be seen in Bahrain as it was impossible to gain access to their roosts in Iran, Saudi or elsewhere. His reference was an internationally published book of birds that specifically identified the birds’ roost in Bahrain as the very location where our tree stood. Our friends brought the bird-lover to our house and he was was in seventh heaven when he realised his luck in being able to see, close up, the activities of the incredibly rare Grey Hypocolius. We learned that the location of this large acacia tree was in fact the site of the highest ever recorded colony of Grey Hypocolius to roost at one time, numbering one thousand, five hundred.

Over the next few months we grew to learn more about the birds. Unlike other species that fly in a straight direction from one perch to another and usually at a leisurely pace, the hypocolius flies directly upwards at speed into the wind, flying high into the sky where it catches the air stream to propel it towards its feeding grounds. The birds usually arrived in Bahrain in late October and remained for almost six months before they departed in April.

Their daily routine never varied. At night, one large group would spend the night deep inside the sweeping branches of the large acacia, while others slept in nearby palm scrubs and smaller acacias. Perhaps the large acacia dwellers were the ‘senior’ or ‘leader’ tribe and the rest came from different migration areas. At sunrise, the site came alive as hundreds of birds darted out of the surrounding thickets and swooped to the large acacia, decorating its branches in a mantle of grey. It was transformed into an avian ‘Heathrow’. Their soft ‘mewing’ became louder and they would chirp and chatter excitedly as they discussed their plans for the day. Fluttering, darting back and forth, swapping places, jostling for position on different branches, they prepared for take off. 

Monitoring the precision of their flights was like being a plane-spotter; first, at a pre-arranged signal, one flock would flutter to the topmost branches and perch, facing into the wind, and then suddenly, more than a thousand birds ceased chirping and remained in absolute silence until the 'take-off’' signal was given. Then, the first group shot straight up into the air like a NASA space launch to catch the wind, and within seconds had climbed so high that they were barely visible.

Then another flock took their place and settled on the top branches, each passenger jostling for the best seat until there was a full planeload. Again they all fell silent before take off, then rose as one, into the air to catch the wind-stream before veering off in a different direction to the first flock. Just like at Heathrow airport, this pattern continued in regular intervals, taking off a minute or so apart and continued for about twenty minutes until the tree was empty. The birds were well behaved; no queue jumping was tolerated as any miscreant was hustled off the branch. At times up to one hundred birds took flight simultaneously and reached heights of a hundred metres before they found the right flightpath. 

On misty mornings, the birds would make a few false starts if they hadn’t reached their desired height and would flutter back to the treetop until they gained their equilibrium. Then they would try again to catch the current which propelled them high into the sky.

One very foggy morning the flight plans were badly delayed. When the fog lifted slightly, the first group took off hesitantly, followed too closely by another flock. They all became disoriented in the mist and collided, then swooped back down into the lower branches and postponed their flights, allowing smaller groups to take off before them. This lot cleverly flew low, beneath the mist. It was fun to watch the local bulbuls trying to imitate the Hypos but lacking the streamlined thrust and skills of their feathered colleagues, they kept colliding and falling back onto the tree. Cheeky sparrows who were normally no match for the Formula One speeds of the Hypos thought their luck was in and tried to sneak onto the 'take off' branches - but they were chased off.

At sunset, tiny specks appeared high in the in the opal twilight sky as the birds returned from all directions, flying at full speed towards the acacia where they circled briefly to get their bearings, before plummeting down on closed wings, their long tails stabilising their descent like jets. The chirping and warbling again reached a crescendo as over one thousand birds jostled for space, chatting, sharing news and cAt sunset, similar to the sunrise take off routine, at each landing, the noise ceased for a second before starting up again. 

The precision and timing of the birds’ flight routines were spot on. At dawn, they had all assembled by 6.15am just as it grew light and by 6.30am, they were gone. At sunset they appeared en masse at 3.15pm and had all landed within fifteen minutes. The Grey Hypocolius is really an incredible bird.

The Hypocolius alight briefly to drink water from lawn sprinklers or irrigation channels in quiet, private compounds but are rarely seen eating from the ground, preferring to feed on unharvested dates, fruit morsels and insects hidden deep within the foliage of palm trees and thickets. Occasionally aerial feeding on insects has been observed.

Sometimes in the mornings when our red pepper tree was in bloom, the birds would hang around eating the berries and perching on our telephone wires, but they didn’t stay long enough to make it a regular feeding stop. 

Word about the birds’ Bahrain habitat reached the outside world and to our amazement, tour buses of twitchers began to arrive at our gate from the US, Sweden, Holland, France and neighbouring Gulf countries. At one stage there were at least two bus loads a week filled with eager birdwatchers who couldn’t believe their luck when they were able to view at first hand, the rare Grey Hypocolius. Cameras clicked, videos rolled as the visitors crept quietly around the tree so as not to disturb their prey. My sons were contemplating setting up a booth to sell water and juices and even hats with ‘We’ve seen the Grey Hypocolius in Bahrain’ emblazoned on them! 

“This is my seven thousand, six hundred and ninetieth bird sighting,” said one elderly American grinning broadly as he climbed back onto the bus. “I’ve travelled all over the world to see as many species of birds as possible and this is the first time I have seen the Grey Hypocolius. I never thought I’d get the opportunity. Now I can rest easy.”

In 1999 we returned from leave to find that all the trees in front of our house had been bulldozed. The lofty, majestic acacia with its large welcoming branches was gone, not even its stump remained. That October, the Grey Hypocolius flew in their thousands from their lofty mountain retreats in the high Karakorams to their favourite roost here in Saar. But when they arrived at the site, they whimpered and mewed in consternation, fluttering around nervously, no doubt wondering where they tree had gone. They tried to find shelter in the scrappy palm scrub on an adjacent empty piece of land and to carry on their traditional lifestyle, flying off each morning to hunt for food but their flight pattern was disorganised; they had lost their citadel. 

The Grey Hypocolius left early that year and over the next few years their numbers dwindled, although some valiant souls continued their journey to Bahrain, searching for possible roosts. Before the birds left forever, I was walking my dog one evening trying to spy the occasional small flock when I stumbled upon a group of twitchers from the Bahrain Royal Irish College of Surgeons, who had sadly missed the glory days of the Grey Hypocolius but were then capturing and ‘ringing’ the birds to identify and count their numbers which at that time, they reckoned were about four hundred. 

Shortly after the loss of ‘our’ acacia, a friend recalled noticing that a large tree in her compound had attracted an unusual type of bird to roost in its branches. One day it was cut down and she watched in dismay as these birds fluttered and circled all night, making crying sounds when they found their home had disappeared. The next day they were gone; she never saw them again.

The country lane outside our gate is today a main highway linking two major arterial road systems and the land of the Grey Hypocolius is now filled with housing estates. In common with much of the world, urbanisation of Bahrain’s original farmlands and wilderness finally drove the birds elsewhere. Few people are aware that an acacia tree in Saar once held the still unbeaten world record of hosting the highest recorded number of Grey Hypocolius ever spotted at one roost.