Welcome to my blog. I am a biologist, based in the south of New Zealand. This blog is a place for me to share my experiences working with and watching wildlife, especially birds. Some of the encounters shared will be the sort of everyday experiences that keep my motivation up at times when I'm stuck in the office, others will be more grandiose wilderness adventures from around the world.
Sunday, 11 September 2011
A lesson on sparrows for Alanis Morissette
In the past few weeks I've been doing a lot of touring of Namibia, visiting and camping in some of the most beautiful spots in the country, and indeed the world. So what to write about... the bull elephants clearing a waterhole of a pride of lions so they could bathe, or the black breasted snake eagle soaring over the plains of the Erongo? Or perhaps fixing the car in the middle of Etosha National Park at sunset, watched by herds of zebra and passing jackals? What has inspired me more than all this has been a bunch of sparrows.
There are around 27 species of 'true' sparrows in the genus Passer found naturally throughout Africa, Europe and Asia, although most people are no doubt most familiar with house sparrows (Passer domesticus). However the most intriguing aspect of the ecology of sparrows is also the reason they tend to be overlooked, and disregarded as a bird worthy of watching (take note Alanis, that really is ironic). Sparrows got the roughest deal in China in the late 1950s, where they were included in the 'four pests campaign', in the mistaken belief that they were consuming large amounts of grain, lowering agricultural productivity, Chinese people were encouraged to kill sparrows (along with rats, flies and mosquitoes). Take note again Alanis-as the sparrows were persecuted and pushed to the verge of extinction, agricultural productivity in fact dropped. Further investigation revealed that the sparrows were actually consuming large numbers of locusts-which were the real threat to agriculture from the beginning. This lesson came too late however, and the 'kill a sparrow' campaign has been linked to a famine resulting in the starvation of over 30 million people.
Getting back to that first irony though-everywhere people settle most birds suffer from localised extinctions, not sparrows however. They manage to not only survive, but thrive in the highly altered environments we offer them-a fascinating phenomenon, although over familiarity with them tends to lead to our overlooking them. As with urban areas throughout the world, house sparrows are also found in african cities and towns. In less modified areas, however, the Cape sparrow, P. melanurus, is much more common. I was surprised to find them in the numbers I did though in the harshest environment I have had the pleasure of visiting-the Namib Desert. The Namib desert covers around 81,000 square kilometres in South West Africa, with rainfall within the desert varying from 5 to 85mm annually. The only occasion I had to get a temperature reading in the area was 44 degrees Celcius... and yet sizable flocks of Cape sparrows were to be seen. With even the hardy Acacia erioloba trees in short supply, the few existing trees were clogged with nests.
So next time you see a few sparrows catching your muffin crumbs at your favourite cafe, don't fob them off as being too common to engage your interest-take the opportunity to get your bird geek on and give them the thought they deserve.
Female Cape sparrow.
Southern Bird Geek trying to fit in with the the local springbok crowd (thanks for the photo, Willem).