Last
week southern Australia experienced a heat wave with four consecutive days of
peak daily temperatures well above 40 degrees Celsius. For all warm-blooded
animals heat stress can be a killer, so as we all know, adopting strategies to
keep cool on extreme heat days is essential for survival.
Keeping
cool involves a range of measures including reducing physical activity and staying
out of the direct sun – that is seeking shade. In addition animal bodies have
evolved ways of regulating internal body temperature. We humans do not have a
cover of insulating fur or feathers that trap heat but we have sweat glands,
which allow us to cool by evaporation.
Many animals and certainly birds do not
have sweat glands so on hot days dogs for example can often be seen panting and most birds are seen breathing through open beaks. This allows for a
certain amount of evaporative cooling, however this comes at a cost – loss of
moisture from the body with the associated need to keep hydrated. So on very hot
days birds tend to reduce physical activity by roosting in the shade and making
many visits, at least for some species, to drink at their favorite watering
point/s. Of course some bird species seem to be able to survive without drinking
water – they obtain all the moisture they need from their food.
Outdoor
bird photography on extreme heat days is generally not on for a range of
reasons and in any case the birds are generally lying low.
However the need for birds to keep hydrated means birdbaths or other fresh
water points can be very productive places to spend time observing and
photographing birds on very hot days.
So
for a couple of hours on two of the extreme heat days I set up in the shade by
a long established birdbath to see which birds came in for a drink and or a bath.
Birds
obviously have favorite drinking and bathing spots they use on a regular
basis. Even with familiar water points most birds still approach them with
caution and are often very nervous when drinking and bathing. Clearly predators
including predatory birds have learnt that watering points can be productive
sources of bird and other animal prey and the prey species know this, hence
their nervous behavior.
This
behavior raises an important animal/bird welfare issue – our presence at a
watering point may keep wary birds away from water critical for their
survival. This is particularly important when the water point is small and the
only one for miles around. So whether we are simply setting up near a water
point to observe or photograph birds or other animals, or perhaps when on
holidays or travelling, we may be tempted to camp near a water point, we need to spare a
thought for the animals that are using the water and ensure our actions
are not keeping them away from water critical to their survival.
The
birdbath I observed was located in a house garden and the birds had adapted to
the presence of humans so my presence some six to eight metres away on a
verandah semi concealed behind some shrubs did not seem to trouble the birds at
all. In addition there were other sources of water nearby.
Over
the few hours I watched the birdbath, thirteen species of birds came in to
drink. The odd bird had a bath, however overwhelmingly they were drinking. I suspect many
birds made repeat visits for a drink at short intervals.
Photographs
were difficult under the dappled light conditions and in addition the bird’s
nervous behavior and behavior towards one another added to the difficulty as they moved about a lot. There were often two or three species present at the
bath together. While there seemed to be plenty of room for all, clearly many birds
had a low tolerance for other birds that were too close, so the odd squabble
broke out.
The birds moved about on the rim of the bath making me wait to capture photos of them in the sunny patches. Here
are some of the photos I managed to capture (click on the images to enlarge).
Sharing
or not sharing?
Spotted Pardalotes were frequent visitors to the birdbath. This may be a family group with one adult female in the foreground and two juvenile females behind - they were happy to share the birdbath. |
Three White-naped Honeyeaters and one Brown-headed Honeyeater share a section of the bath as a Striated Pardalote departs. |
This pair of Honeyeaters, a New Holland on left and a White-naped, argue over one small section of the birdbath. |
The New Holland above has suddenly departed, ending the altercation and leaving the startled White-naped to scramble back onto the bath. |
Birds coming and going were often cause for concern among the nervous birds at the bath. Here a Spotted Pardalote comes in above a Striated Pardalote. |
Nervous
birds keeping an eye on the sky?
Nervous birds at the bath often looked up to check the sky for predators. This is a young Spotted Pardalote. |
The following shots are more or less arranged in order with the most numerous and frequent visitors to the bath first.
A pair of Brown-headed Honeyeaters, the bird on the left is a juvenile - note the bluish eye ring. |
Spotted Pardalotes came in often to drink - this is the very handsome adult male. |
A male Striated Pardalote - this is Southeastern Australian mainland sub species ornatus - note the red spot on wing. |
An adult Eastern Spinebill ready for a drink. |
A juvenile Willie Wagtail - note the brown feathers on the wing. |
Dusky Woodswallows came in as singles or in small family groups. |
There were good numbers of Yellow-faced Honeyeaters around however this was the only one I observed come into the bath. |
I could hear a flock of Silvereyes nearby, however only a few came to this bath to drink. There are other water sources nearby so there was plenty of choice. |
This Grey Shrike-thrush was one of the larger birds to come to the bath. It is wary and checking above for danger. |
A Red-browed Finch catching a small patch of light. |
I was surprised that only one Thornbill came in to drink. I have seen up to four species come in together at our other birdbaths. This is a Striated Thornbill. |
The above thirteen species came to the birdbath while I was there. A pair of Common Blackbirds also came by, but were very wary as they always chose to drink and bath at a nearby bath.
The female Common Blackbird, mate of the male above. It was hot work for the pair feeding young. I suspect they were also taking water to the young in the nest. |
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