Bird Baths

Firstly, it turned out that I was understating the situation with regard to the predicted hot spell that I mentioned three days ago when we were about to plunge into it. Adelaide yesterday, at 44 degrees was officially the hottest city in the world; next was Melbourne. Here in Canberra, where at 600 metres above sea level we're usually spared the real heat extremes, it reached 40 yesterday and today we're on the way to 41 and apparently to the hottest week ever recorded here. 

However my point is not to whinge about the world, but to continue to use the situation as a trigger to talk about how animals use water, whether in extreme heat or not. Last time I talked a little about how animals drink; today I'm going to torment myself slightly (as I sit in front of the fan with a wet towel round my shoulders) with stories and images of animals bathing. In practice it will be mostly about birds, as I seem not to have images of other animals indulging themselves, other than simply swimming as part of their lifestyle.

Firstly, birds don't just bathe when it's hot, though most species do so more often then. Bathing is not optional - it's critical to the continued well-being of feathers, which can be the difference between life and death when a falcon or goshawk's on your tail, which can happen at any moment.

Female Austral Negrito Lessonia rufa bathing, El Calafate, Argentina.
She isn't here to cool down - this is ice-melt water from glaciers, and the air temperature is definitely single-digit!

In a way I should be talking about preening overall, because bathing is an integral part of that, but the careful rearranging of each vane of each feather by the bill, at least daily, is a topic that warrants a posting to itself. Bathing helps remove surplus preening oil which can clog up feathers, as well as getting rid of other dirt, loose feathers and barbules, and parasites.

Eastern Rosella Platycercus eximius, Canberra.
This was in May, a chilly month, so again lowering body temperature wasn't the chief motivation. Note how the feathers are all fluffed up  - this can be to help increase insulation, but when bathing, feathers are erected and separated to expose the skin between the feather bases to allow water to wash the skin and expose the entire feather.

It's still not a passive process though. In fact a bathing bird works very vigorously to force water into the feathers, pushing the breast into the water and rocking hard from side to side, hurling water around with the wings. 

European Blackbird Turdus merula (above and below), Melbourne.

Red-rumped Parrots Psephotus haematonotus, Lake Cargelligo, New South Wales.

Australian White Ibis Threskiornis molucca, Darwin.

After that water is thrown onto the back, again with the feathers first raised, then lowered to squeeze the water through them.

Golden Whistler male Pachycephala pectoralis, Canberra.

Perhaps surprisingly, even waterbirds need to bathe vigorously. This shouldn't be too surprising actually, as such birds need waterproof plumage, so must make a special effort to get their body surface and under-feathers wet.

Magellanic Penguins Spheniscus magellanicus, Strait of Magellan.

So far these pictures were taken in natural settings, but a bird bath is one of the most valuable pieces of assistance that we can offer birds, up there with growing local native plant species.

Double-barred Finches Taeniopygia bichenovii and Chestnut-breasted Mannikins Lonchura castaneothorax, Darwin.

Silver-crowned Friarbird Philemon argenticeps, Darwin.
Here the head is thrown back and the wings are arched to form a bowl to hold water on the back.
(Below is the bird afterwards, so you have some idea as what it actually looks like!)

Superb Fairy-wren Malurus cyaneus, Canberra (our yard in fact), fully submerged.

At the end of the process the bird is sodden, and needs to squeeze water from the feathers and dry them out to regain their essential insulation properties.

Dusky Honeyeater Myzomela obscura, Darwin.

Noisy Miner Manorina melanocephala, Canberra.

Birds are adaptors however - indeed to live in suburbia you must be able to adapt to unfamiliar conditions. Part of this is the enthusiasm with which some species have adapted to sprinklers. This is not entirely new behaviour, but based on rain-bathing, wherein the bird hangs upside down to allow water to penetrate.

Sulphur-crested Cockatoo Cacatua galerita, Canberra. Hanging from eucalypt foliage to expose its breast to the rain. This is also known as leaf-bathing, as water shaken from the wet leaves is also utilised.

Crested Pigeon Ocyphaps lophota, Canberra (our yard again).
The sprinkler is to the bird's left, and it was turning from side to side and raising the near wing to let the water in. This is learned behaviour, as it's hard to imagine a natural situation where water would be coming from the side.

Just a couple more things. Firstly, one token non-bird.

African Bush Elephant Loxodonta africana, Okavango Delta, Botswana.
And OK, it's not actually in water, but it's just left it!

Significantly, many birds bathe in dust - obviously when water is absent, but also when it is not. In fact some species often follow a water bath with a dust bath, and in doing so seem to increase removal of both parasites and surplus preening oil.

House Sparrow Passer domesticus, Isla de Chiloe, Chile, dust-bathing. Plenty of water is available here.

By the time I'm back here with the next posting, things will be cooler here - for a while at least. Birds will still be bathing assiduously however.

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