Birds vulnerable to trickery
Birds can be influenced in the same way as human consumers as they work out what to eat, says a study.
Research by British and Canadian scientists found that their preferences could be manipulated by using techniques to those employed in supermarkets.
In shops, the correct positioning of items to maximise sales is regarded as a science.
One tactic used by large stores is to place an eye-catching "decoy" product right next to stocks of the product they actually want to sell.
The attractiveness of the target brand is enhanced by this, and sales go up.
However, the team of researchers, including some from Newcastle University, UK, found that birds appear to be equally vulnerable to such trickery.
They studied the behaviour of 12 rufous hummingbirds, which live in the Canadian Rocky Mountains.
The birds feed on the nectar of flowers in their valley, and need to eat almost constantly due to their high metabolic rate.
They tend to return to exactly the same area for their meals.
This research shows that birds, like humans, are actually more irrational than we previously thought
Dr Melissa Bateman, University of Newcastle
The researchers created a "mock" flower bed on a Perspex sheet containing various small feeding wells containing sugar solutions of varying concentrations.
In normal circumstances, the birds would head for flowers with larger volumes of nectar, as opposed to flowers with lower volumes of sweeter nectar - as this choice would provide them with more energy.
However, the introduction of an attractive "decoy" flower placed adjacent to the target flower changed this behaviour.
The birds headed for the target flower regardless of whether it had more or less sugary solution.
Dr Melissa Bateson, one of the lead researchers, said: "This research shows that birds, like humans, are actually more irrational than we previously thought.
"They are prepared to make an instant decision based on the choices they have available at the time.
"The technique could be potentially applied to conservation projects - such as those focused on protecting certain species of plant.
"Hummingbirds have an important role in pollinating flowers - introducing decoy species which enhance the attractiveness of the target flower may help achieve the conservation goal."