The many voices of birds

Although the legendary American naturalist and bird language master, Jon Young and other northerners talk of ‘5 voices of birds’, I’m inclined to disagree. Maybe it’s just bird-nerd semantics, or maybe it’s because Aussie songbirds have had at least twice the span of time (literally tens of millions more years) to work on their collective lexicons, but to my mind we’re dealing with at least 9 vocal expression categories.

I need to clarify something here. The distinction between the courtship call, mimicry and territorial call of a bird like the superb lyrebird is, on the face of it, open to some interpretation. Afterall, it is not unusual to record a single male lyrebird making a series of calls over the space of some twenty minutes that includes all three types of what I’m calling unique voices. But on closer inspection of the behaviour, ecology, seasonal context and circumstances for when each call occurs just on their own, it is possible (I think) to say that each has a distinctly different purpose and meaning.

For some species, separating these voices is fairly straightforward, but in a great many species it requires crazy amounts of field time to observe how and when each voice is used, and what effect is produced in other birds. Thus, the categorisation of songbird voices is always going to be a fluid practice, open to new interpretations and correction as new insights and observations come to hand.

The high-pitched “tink” call of a green catbird, for instance, seems obvious enough as a contact (or companion) call, yet I have been left wondering what the heck ELSE it might mean when a group of catbirds clamber around excitedly yowling and tinking at each other for hours in breeding season. Possibly there are subtle variations in their contact calls that my ears cannot distinguish (despite my clearing them of unsightly ear hairs regularly) that change the meaning under some contexts??

Nature is complex and doesn’t have to conform to handy rules, especially my rules. If you think I have any of these calls in the wrong voice category, please reach out to let me know, I welcome the evolution of new understanding.

Here’s my current working list, based entirely from personal observation of songbirds on the north coast NSW (though I suspect there are substantial commonalities across Australia) –

A quick word about recording bird voices

During the 2021 Covid lockdowns I set myself the (rather unrealistic) challenge of recording examples of each and every one of these 9 voices for a single species of bird in my local forest. I purchased a directional (so-called shotgun style) microphone, professional sound recorder and headphones. Rather predictably it turned out to be a task that will run over a lifetime.

For a start, I hadn’t factored in how saturated our soundscapes are with incessant background human noise. Subtle to the human ear, this noise becomes a major annoyance when using powerful amplification equipment. What had been a general dislike of sit-on lawnmowers, obviously blunt chainsaws and the neighbour’s kids on 2-stroke motorbikes (or for that matter, my wife’s sneezing) soon grew to near-murderous proportions. Having incredibly sensitive hearing must be such a diabolical curse in today’s modern industrial age of omni-human-noise dominance. No wonder whales beach themselves.

Recording birds during the Covid lockdowns was blissful – as no-one was allowed to fly, I didn’t have the usual cacophony of rumbling noise pollution from overhead passenger jets!

Anyhow, even though I’m still chasing that initial objective there’s been a bit of ‘mission creep’ and now I’m just trying to record examples of each voice no matter which species of bird is talking. The following recordings are the fruits of that ongoing labour.

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