How Emperor Penguins stay underwater for 27 minutes
Press release issued: 2 September 2013
New research has revealed how the Emperor Penguin is able to dive to depths of over 500m and stay under water for up to 27 minutes – deeper and longer than any of its fellow avian species.
Researchers from the University of California will be presenting their new findings at the International Penguin Conference (IPC) which begins in Bristol today [02 September].
It's the first time the conference has been held in Europe, with 200 delegates from 30 countries sharing their latest research and knowledge at the University of Bristol and Bristol Zoo Gardens between 2 and 6 September.
Alexandra Wright and Dr Paul Ponganis investigated the heart rate response of Emperor Penguins as they made foraging trips to sea from the Cape Washington Colony in Antarctica.
They measured heart rates using an electrocardiogram (ECG) recorder and looked at dive behaviour with a time depth recorder (TDR) and found that the penguins slow their heart from the normal rate of around 70 beats per minute to as low as 10 beats per minute.
Emperor Penguins also have unusually structured haemoglobin to allow it to function at low oxygen levels, solid bones to reduce barotrauma - physical damage to body tissues caused by a difference in pressure between a gas space inside, or in contact with the body, and the surrounding fluid, and the ability to reduce metabolism and to shut down non-essential organ functions.
The profound decline in heart rate - known as bradycardia – decreases oxygen consumption, conserves the respiratory and blood oxygen stores, and isolates muscle, which must rely instead on its own oxygen store which is bound to the muscle protein, myoglobin.
Although this heart rate response contrasts with other birds and terrestrial mammals, it is similar to the dive response of marine mammals.
Archbishop Desmond Tutu recorded a special video message to launch the event, which will see delegates sample papers on everything from “monitoring global penguin population change” to “the power of poo”.
The public are also invited to get involved thanks to two public events this week. Bristol University graduate Elizabeth White, one of the directors of the popular Frozen Planet series, will be part of a free panel discussion entitled ‘Penguins on Film’ being held in the Wills Memorial Building on Wednesday, 4 September.
Footage from the BBC Natural History Unit, captured by a crew who spent four months with a penguin colony in the Antarctica, will show how Adelie penguins steal stones from its neighbours’ nests to elevate and protect their eggs from run-off when the Antarctic ice melts.
Captivating slow motion footage will illustrate that penguins can ‘fly’, showing how Emperor penguins – the largest of all penguins, reaching up to 120cm tall – manage to get airborne by swimming at speed towards the surface of the water and landing back on the ice.
There will also be an opportunity to learn more about the African penguin at Bristol Zoo Gardens on Saturday, 7 September, with activities for all the family and the chance to meet scientists and conservationists who work with African penguins in South Africa and Namibia.