Tuesday, November 4, 2014

Book Review: Where Song Began

Where Song Began: Australia’s birds and how they changed the world by Tim Low, 2014, Viking.
Where Song Began is such a fascinating, enjoyable and richly detailed story that I haven’t been able to review the book in the conventional manner. I still have much reading to do and so instead will tell you some of the things that interested me.

Being swooped by birds has not been a common experience for me, barring the odd plover fly-by when crossing a football field on my daily walk. This year, in Brisbane, while I sat near the café in the Botanical Gardens, a kookaburra egged on by a pair of noisy miners, took the last of my lunch from my fingers. The next day, while I again ate and drank, this time under cover at a student cafeteria, a pair of noisy miners flew in, grabbed the sugar that I don’t use from the table … you know, one of those little sachets … and proceeded to feed from the tube as if it was a flower.

In Where Song Began, I became engrossed in the reasons for our birds’ unusual behaviours. Tim Low explains that here many trees and plants are pollinated by birds. Nectar birds on other continents tend to be humming birds. Here we have a huge range of honey-eaters of all sizes and many parrots that live on nectar, not to forget mammals such as sugar-gliders and fruit bats. Trees in flower are defended by birds for the use of family groups. Noisy miners grow into tribes of up to 200 members. Fascinating stuff.

Australian birds accordingly are aggressive for the very good reason that many Australian trees have evolved an attractive high energy food that can last for days. Sixteen flowering banksia cones producing nectar for twenty days can constitute a honey eater’s territory that will need to be protected against others.

Not only are Australian birds aggressive against people whom they see as dangerous to their young, or their food source – the currawongs in my backyard almost took a piece out of me when I came dangerously close to the fruiting bangalow palm – they are also aggressive against other birds. We’ve all seen noisy miners chase off the competition as well as magpies taking on channel billed cuckoos dangerous to their eggs and nestlings.

Australian soils are by and large impoverished. How often have we been told not to add garden-strength fertilisers? Not to dump rich garden waste. The theory by Orians & Milewski (2007) goes that our trees cannot convert the carbohydrates they make into tissue or seed due to the lack of soil minerals. “The surplus sugar is fed to birds as nectar in return for pollination. Birds can thrive on this sugar as they eat insects as well to provide the missing nutrients.” (Low, p12)

I read about Ice Age survival. With no wind-blown seed, Australian trees did not move in the last period of extreme climate change and therefore are not expected to move in the present period of swift climate change. In the past, trees survived in small pockets, refugia, because their pollinators wandered the landscape searching for trees in flower. There’s a case there, says Tim Low, for concentrating our conservation efforts on birds and bats.

Due to my new interest in owls, I looked for them in this story. It turns out they are late arrivals on this continent, with a presence of only a few million years. Why then, I want to ask Tim Low. He makes the case that since Australia does not have a suite of large mammalian predators, birds have taken up those niches. So why owls so late in the piece? What were the predators before them?

Among the trees that can only spread by the dispersal of their fruit, another interesting resonance is the number of large-fruit fruiting trees that no longer have a dispersal agent. Eleven local trees including the Davidson Plum are now dispersed mainly by human actions. Together they apparently prove the once upon-a-time existence in this region of a dwarf cassowary. I’m looking forward to the time that they find that birds DNA in amber and we can have it revived Jurassic Park style.

The pied currawongs now taking over suburbia and surviving in towns over winter, gladly feed on privets, cotoneaster, camphor laurel, firethorn, hawthorn and holly. Come spring they are the main predators of small nestlings and eggs. Robins are vulnerable to extinction if not already threatened. Another reason for continuing to educate gardeners. Birds can be brought back from the brink if we replace exotic berry bushes.

These facts make up only some of the fount of knowledges in this amazing story, and not even the primary premise. I have to read the book again to take in that, but couldn’t wait to share it with you, and encourage you to beg borrow or buy Where Song Began. You won’t be disappointed.

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