Western Daily Press (Saturday)
Pheasants keep a cool head when tempers flare
Maintaining a pecking order means battle stations among pheasants, but research shows they are far from hot-headed – in fact quite the opposite, reports Rod Minchin
PHEASANTS’ heads cool rapidly as they prepare to fight – then heat up afterwards, new research by West Country scientists shows.
Scientists used thermal cameras to watch juvenile pheasants to see how their temperature changed during aggressive interactions that establish the pecking order.
They found that pheasants – both the instigator and the recipient of the aggression – grew more cool-headed before a fight, due to a stress response in which blood rushes to the body’s core.
Their heads became hotter again after the confrontation, as normal blood flow was restored.
“We were surprised that both individuals in these aggressive encounters followed a similar pattern of cooling and heating,” said Dr Tim Fawcett, of the University of Exeter.
“We expected that a fight would be more stressful for the pheasant on the receiving end of the aggression, and therefore that we’d see a stronger response in them.
“We can’t say for certain what causes this pattern but it could be that maintaining a place at the top of the pecking order is just as stressful as being at the bottom.”
While male and female pheasants followed a similar pattern of cooling and heating before and after a fight, females were cooler on average.
“Thermal cameras provide a unique opportunity to non-invasively measure dynamic changes in physiological state over a short period of time,” said Dr Mark Whiteside, from the University of Plymouth.
“Using this technique we were able to measure responses to aggressive interactions, in semi-natural environments, in real time.”
We were surprised both individuals followed a similar pattern of cooling and heating dr tim fawcett
Changes in blood flow are an important part of the stress response in multiple animal species, in a variety of situations.
The pheasants in the study were six or seven weeks old and were captive at the time, but later released into the wild. The findings come 100 years after Norwegian zoologist Thorleif Schjelderup-Ebbe coined the term “pecking order” in his PhD thesis about chickens.
■ The paper, Hot-headed peckers: thermographic changes during aggression among juvenile pheasants (Phasianus colchicus), is published in the journal Philosophical Transactions of the Royal Society B.