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Three Million Swallows
What are the Swallows twittering about?
It is about half an hour before sunset and a small group af people are sitting on deck chairs and blankets on the grassy slopes of Mount Moreland. In fact there are five separate groups: five women are discussing the merits of Face book and Twitter as an opportunity to meet new friends while sipping their wine; an elderly couple sit on a wall some 20 meters away with binoculars around their necks in quiet conversation; two families are laughing and chatting while small children explore the surroundings. The children are more interested in the huge airplanes taking off from the nearby international airport than the reason that has brought this diverse group together on this hill overlooking a big reed bed in the swampy area some 400 meters below. Behind these groups are the representatives of the Mt Moreland Conservation Area who sell a variety of trinkets and collect a R10 donation from visitors.
The advert collected from the local tourism office gives the information about the 3 million Barn Swallows that fly in to roost in the reed beds about half an hour before the sun sets. I am not certain who counted them but there is no doubt that there are many, many swallows that are beginning to arrive. They come from all direction, first a few at a time and then hundreds and thousands. Circling the sky above the swampy area they descend in huge flocks down into the reeds. The sky as we look at it is speckled with moving black dots and as some descend others are arriving from all directions. In the background the town of Verulem and the grassy green hills surrounding it catch the last rays of the sinking sun.
The visiting birdwatcher are suitably amazed, the organizing representative answer question and lend binoculars to those who do not have, and the kids are impressed as another plane takes off from the nearby airport and passes over our viewpoint. In just a few more minutes the last of the Barn Swallows have dropped into the reeds and cupping your hands over your ears you can hear them twittering, perhaps saying good night to each other.
These Barn Swallows make a bi-annual journey of over 12 000 km from Europe to South Africa to avoid the cold temperatures during the northern winter. They fly about 300 km a day and so spend a long time of their lives on this epic bi-annual migration pattern for survival. These small birds that spend the summer in Kwa-Zulu Natal leave their roosting places shortly after sunrise every morning and forage for food in the surrounding areas before their return at sunset. They drink water by flying low over dams and lakes and picking up fluid in flight. For the rest of the day they hawk small flying insects and bugs fattening themselves up for the trip north that will begin in March as summer ends. Apparently birds know when to leave not according to changing temperatures but according to the length of the days.
According to researchers between 22 and 45 million Barn Swallows migrate to Africa from Western Europe and a similar number from Eastern Europe and Asia every summer. Their main food is flies, ants,spiders and other bugs. Although not an endangered species many die in times of drought and due to poisoning of fields to get rid of the Quelias that threaten the maize and wheat crops in Africa. Some roosting areas have been used by large groups of Barn Swallows of up to three million for more than 50 years. Records from the Mt Moreland area indicate that the reed beds just outside Durban North have been used for almost that long. This area has now been declared an IBA (an Important Birding Area) and as such enjoys the protection provided for such areas.
An IBA is a specific area of value for the conservation of birds recognized by the International Bird Life Association. It promises conservation of that area because of its value to the bird population there. There are over 10 000 such areas worldwide and they play a valuable part in the preservation of the natural resource that birds are. Some of the Vulture breeding areas in South Africa qualify for such recognition and protection. Mt Moreland is undoubtedly worthy of IBA status and being so close to a major population area provides a great opportunity to teach young people about bird life. It is also a good place to sit and discuss the merits of Face book or Twitter while enjoying a sun-downer in a beautiful summer evening. The Swallows may vote for Twitter if you listen carefully.
Sources: Roberts Birds of Southern Africa