'Cacophany' is a word we all know, but how about biophony (the totality of sounds produced by animals), geophony (the sounds produced by water, wind and other non-living forces), anthrophony (all sounds produced by humans) and its subset technophony (machine sounds)?
These terms come up in an interesting academic article calling for more research into the geographical variation in sounds, which, needless to say, often come from birds. In ‘The silence of biogeography’ biologist Mark Lomolino and two colleagues note that bioacoustics (study of animal vocalisation and sound perception) has expanded into the geography of sound, by looking at how soundscapes – the collection of sounds that characterise a particular landscape – vary from place to place and over time.
Soundscapes matter greatly in my book Where Song Began. In the very first paragraph I mention 19th century claims that Australian birds could not sing, and rather than dismissing this as chauvinism I suggest they have some validity:
“Australia does sound harsher than your average field or forest overseas. Like a person vomiting was how Gould described the call of the little wattlebird, a large honeyeater. The great bowerbird’s hissing is described in one 2001 guide as a cross between tearing paper and violent vomiting.”
A paper that came out in Science a fortnight before Christmas counts as the most important work on birds this century, by offering something that has eluded science for well over a century – a reliable tree of life for the world’s bird orders.
Biology was shaken some years ago by evidence implying that parrots and perching birds are closely related.
Links between the bird orders have proved extremely difficult to determine, and except for intelligence and a facility for learning songs, there is nothing about perching birds, which include honeyeaters, crows and sparrows, to suggest they are related to parrots. Their beaks and feet are very different.
The evidence that emerged was genetic, but some genetic studies did not find this relationship, so in my book Where Song Began I equivocated, describing the relationship as probable but not proven.
Lyrebirds are the ultimate high achievers: the world’s best songsters, the world’s oldest songbird line (along with scrub-birds), beloved cultural icons that grace our coins, and spectacular ecosystem engineers. They may be something else as well – birds that save human lives.
The ‘ecosystem engineer’ tag refers to the changes they make when they scratch the ground to unearth insects. One lyrebird in a year can shift 200 tonnes of soil and litter per hectare, causing soil erosion and uprooting ground-hugging plants, including, in Tasmania, an endangered orchid.
A new paper by Daniel T. Nugent and two colleagues takes the engineering concept further by concluding that lyrebirds reduce bushfire risk by burying leaf litter and uprooting the grasses and bracken that carry fire.
[This is a book review that appears in the Spring 2014 issue of Wildlife Australia magazine.]
With animals continuing to go extinct any book that eyes extinction in a fresh way deserve our attention. Lost Animals is significant because it features all the world’s extinct mammals and birds that are survived by photos. As Erroll Fuller says in his introduction, about the difference between paintings and photos:
"It seems that a photograph of something lost or gone has a power all its own, even though it may be tantalisingly inadequate".
That is what I felt after paging through this book and staring at the 28 species that look out from the plates. The lowest resolution images, those of an imperial woodpecker in Mexico (taken from film footage), struck me as especially powerful, perhaps because they resemble scenes out of a dream, one of those happy dreams we wish we could return to. This footage only surfaced in 1997, 41 years after it was taken, and the quality is poor because the film is old but because the biologist who shot it was sitting on a mule. Also very potent are some of the photographs in colour, because the animals look too vivid to be defunct, and because the colour tells us the extinctions happened recently.
Fuller provides dates of extinction or last sightings, including 2004 for the Hawaiian po’ouli (a bird), 2002 for the Yangtze River dolphin, 1988 for the Hawaiian ‘o‘u (another bird), 1985 for the Alaotra grebe of Madagascar and Kauai ‘o’o of Hawaii, 1984 for the Guam flycatcher, 1983 for the Aldabra brush warbler, and so on and so on.
In September I visited Java for ten days to see rainforest birds and other wildlife. Java holds special interest for anyone wanting to understand the arcane topic of how Asia and Australia exchanged birds in the past. Its conservation problems are dramatic. The first time I went there I found a dead rhinoceros.
As recently as 10,000 years ago Java, Sumatra and Borneo were part of the Asian mainland because a cooler climate lowered the sea, exposing the Sunda Shelf. Australia is much closer to mainland Asia when seas are lower, at which times the climate is drier as well as cooler, and savannah rather than rainforest may have dominated the Sunda shelf. The eastern half of Java (and its satellite island Bali) are a drier today than Borneo, Sumatra and Malaya, and it is in Java and Bali that we have the best chance of locating the birds that characterised the more open habitats of the Sunda shelf in glacial times.
The golden-headed cisticola, a cute bird with a commanding voice, is an obvious candidate. It is a recent coloniser of Australia that is common in Java and Indochina but absent from Malaysia and Borneo (except as an apparent vagrant). On Sumatra it is believed to be a recent coloniser (MacKinnon & Phillipps 1993) exploiting grassy clearings created by people. While it is possible that this small bird reached Java directly from Thailand, it is more likely that during a glacial period there were mosaics of rainforest and savannah linking Thailand to Java, providing almost continuous habitat for this small grassland bird, which was then able to reach southern Indonesia and Australia.
I am on Christmas Island where Cyclone Gillian, which struck in February, showed her anger, as cyclones do. A stretch of rainforest in which Abbott’s boobies were breeding lost its canopy, and nests were destroyed and chicks killed. Many chicks rescued from the forest floor by national park rangers were reared and released.
The cyclone probably helped one bird, the Christmas Island goshawk, judging by all the sightings over the past week. I am here as a guide on the Christmas Island Bird’n’Nature Week, now in its ninth year, and fellow guides Mark Holdsworth and Sue Robinson, who band goshawks as a bird week activity, had more success catching goshawks than usual.