Study in Cornwall finds Jackdaw chicks learn about predators from adults
Scientists found the chicks became extra alert when they heard a predator’s call paired with alarm calls from their parents
A study in Cornwall has found Jackdaw chicks are learning about predators by listening to adults.
Scientists played recordings of predator calls to chicks in their nests – and paired the sounds with either adult jackdaw “alarm” calls or “contact” calls that indicate no danger.
The chicks in the study were 20-30 days old, and sound was played at 39 nests in total.
It found the chicks became more vigilant when predator sounds were paired with alarm calls, indicating they had learned to fear the predator.
The research by the University of Exeter also tested the response of chicks to non-predatory birdcalls and found that chicks did not learn to fear this even when paired with alarm calls.
Researchers believe this suggests evolution has shaped learning processes to ensure only “biologically meaningful” links are learned – so animals don’t waste energy responding to things that pose no threat.
The study was led by Hannah Broad during a Master's by Research at the University of Exeter's Penryn Campus.
Broad said, “Our study shows that nestling jackdaws can learn about dangers they might encounter in the future by listening to adults."
"As they nest in cavities, jackdaws are fairly safe as nestlings. However, learning through trial-and-error after leaving the nest can be dangerous – so social learning as a chick could be highly valuable.”
The recorded birdcalls came from a possible predator of jackdaws, the Eurasian goshawk, and a non-predator, the American golden plover.
The study took place in Cornwall, where these species' sightings are rare, ensuring the jackdaw chicks had not previously been exposed to these calls.
However, scientists say the reaction to the goshawk call (when combined with adult jackdaw alarm calls) suggests jackdaws have an evolved predisposition to learn about birds of prey.
Jackdaw chicks became about twice as vigilant in response to goshawk calls – with vigilance measured by chicks raising their heads above their shoulders.
“Learning to associate events that occur together by chance – for example becoming scared of any birdcall heard at the same time as alarm calls – could cause chicks to learn the wrong information,” said Professor Alex Thornton, from Exeter’s Centre for Ecology and Conservation.
“The chicks in our study learned to fear goshawk calls due to social learning from adults, but our findings suggest evolutionary processes may tailor what can be socially learnt.”
With goshawks expanding their range in the UK, Cornwall’s jackdaws could soon be exposed to these predators.
Professor Thornton said: “As a result of rapidly changing environments, the ranges inhabited by many species are changing.
“Learning processes like the one examined in this study might give species a chance to adapt to new threats.”