September 11 is auspicious for me not because it happens to be my birthday and the date of the infamous 9/11 terror attack on the World Trade Centre in New Year – it’s a day to watch for the arrival of our welcome swallows.
They should have turned up in good number just before September 11 but any delay makes me nervous. With growing reports of the decline in bird numbers, including swallows, my birthday has also become an unofficial cut-off point in the timetable I have drawn up over the years for the arrival of the traditional harbingers of spring. If they have not turned up well into September, I start to worry.
The swallows are usually guaranteed to arrive during the first weekend of September, sometimes arriving a little earlier and sometimes delayed by a few days.
Last year, however, they were particularly late. I waited until near the end of September before a decent number arrived. It has been the same this year.
It’s dangerous to read too much into the late arrival of the migrants, usually led not by the swallows but by the striated pardalote. Adverse weather like strong headwinds and ice and snow on migration routes – which can affect the abundance of both nectar and insect food – can prompt migrating birds to hunker down wherever they have reached on their epic journeys, or delay the start altogether.
I hold my breath, however, as the first weeks of September pass. Although we read frequently of decreasing numbers of our birds, the loss often goes unnoticed in the suburbs where a smaller variety of more common birds proliferate.
An absence of familiar migratory birds will become obvious, however, if those eagerly awaited at the end of winter fail to show. The swallows and the closely-related tree martin are a case in point.
For the 24 years I have visited the Waterworks Reserve near my home, the welcome swallows have not only arrived each spring but have reared young there.
Although not in critically low numbers, the swallows are among the majority of bird species in decline and I live in fear that one season they might not arrive in sufficient numbers to build nests and rear young, or not arrive at all.
There is no greater symbol of bird migration than the swallow, and the spring arrival of the respective swallow species across the world is celebrated in dance and song.
In some western cultures it was once thought the swallows migrated to the moon until bird-watching pioneers in far-flung places realised the birds they were observing were the same species seen at home at other times of the year.
Our welcome swallows do not engage in inter-continental travel like the European ones which fly to Southern Africa. Ours have a shorter journey, to New South Wales and Queensland.