Many arid zone birds who need to move long distances to a source of drinking or bathing water do so in the cooler parts of the day to avoid overheating and dehydration while on the move.
Interestingly, emus are quite dependent on water for drinking. Studies of both captive and free-ranging emus from arid and semi-arid environments have shown that they need to drink between 1 to 1.5 litre of water per day to maintain body water balance.
On several occasions in the 1980s I observed emus bathing in seawater at Kanidal Beach, Eyre Bird Observatory. Each observation was mid- or late-afternoon, i.e. during or just after the hottest part of the day, so I’ve always assumed that the bathing was a means by which emus cooled down. Emu footprints were often seen in coastal dunes between the observatory and the beach, suggesting that bathing at the beach was more frequent than what was observed.
Emus have the smallest brains relative to body size of any bird species. The brain is kept cool in part by losing excess body heat through panting and bare patches of skin on the head, neck and legs (known as thermal windows). When emus drink water from dams, cattle troughs and wetlands on a hot day they usually splash water over their head and neck to increase the rate of heat loss through evaporative cooling.
In November 2010 near Denham, WA (Shark Bay), I observed a male Emu with eight chicks approach a salt lake near the ocean and bathe up to the belly, the chicks, however, stayed out of the water.
The funny thing was that although the days were hot (up to 35), this was very early in the morning when the heat wasn’t a problem. Perhaps it did have something to do with getting rid of parasites.
John,
Many arid zone birds who need to move long distances to a source of drinking or bathing water do so in the cooler parts of the day to avoid overheating and dehydration while on the move.
Interestingly, emus are quite dependent on water for drinking. Studies of both captive and free-ranging emus from arid and semi-arid environments have shown that they need to drink between 1 to 1.5 litre of water per day to maintain body water balance.
Stephen Ambrose Ryde NSW
On several occasions in the 1980s I observed emus bathing in seawater at Kanidal Beach, Eyre Bird Observatory. Each observation was mid- or late-afternoon, i.e. during or just after the hottest part of the day, so I’ve always assumed that the bathing was a means by which emus cooled down. Emu footprints were often seen in coastal dunes between the observatory and the beach, suggesting that bathing at the beach was more frequent than what was observed.
Emus have the smallest brains relative to body size of any bird species. The brain is kept cool in part by losing excess body heat through panting and bare patches of skin on the head, neck and legs (known as thermal windows). When emus drink water from dams, cattle troughs and wetlands on a hot day they usually splash water over their head and neck to increase the rate of heat loss through evaporative cooling.
Stephen Ambrose Ryde NSW
In November 2010 near Denham, WA (Shark Bay), I observed a male Emu with eight chicks approach a salt lake near the ocean and bathe up to the belly, the chicks, however, stayed out of the water.
The funny thing was that although the days were hot (up to 35), this was very early in the morning when the heat wasn’t a problem. Perhaps it did have something to do with getting rid of parasites.
John Leonard