Experiment finds parrots think in economic terms

Sometimes, it pays to wait – for example when it comes to choosing between an immediate, but small, reward and a greater reward at a future date. 

On occasion, both humans and animals have to forgo an immediate reward for a delayed benefit. Deciding whether the wait will be beneficial requires the capacity to control their immediate impulses and assess the expected final outcome.

Parrots have clearly grasped this concept: true to the motto “better a bird in the hand than two in the bush”, they are capable of learning when it is better to forgo an immediate reward.

Researchers at the Max Planck Institute for Ornithology in Seewiesen, Bavaria have discovered that these birds turn their noses up at inferior food if they can count on getting more nutritionally valuable food at a later time – a capacity, which may well secure their survival in the wild.

The researchers experimented with 36 parrots from the Loro-Parque Foundation including soldier-, blue-throat- and blue-headed macaws as well as grey parrots.

First, they taught the parrots to exchange tokens for food, whereby different tokens represented cereals and sunflower seeds as well as walnuts – for bird food of a low-, medium- and high nutritional value.

Then, the parrots were invited to choose between an immediate reward and a token that they would later be able to exchange for bird food of a higher nutritional value. In control tests, by contrast, the birds only received a food reward of equal or lower nutritional value.

In this way, the researchers tested whether the birds were actually making their decisions based on economic considerations or selecting the tokens for other reasons.

The results showed that the parrots only forgo an immediate reward in favour of a token if it represented a higher nutritional value than that of the immediate reward.

“Therefore”, as Anastasia Krasheninnikova, the lead author of the study explains, “parrots are capable of making a rational decision and maximising the benefit to themselves”. Whereby, she says, the birds performed as well as chimpanzees in similar experiments.

The study also provided evidence for the fact that other factors can also influence the birds’ decision-making. For example, in some of the control trials, grey parrots also chose a token instead of food even if they would later only be able to exchange it for food of exactly the same nutritional value.

“Clearly”, Krasheninnikova explains, “the tokens have acquired a special value in the eyes of the birds, for which they are even prepared to forgo an immediate food reward – given the well-developed play instinct of these birds, one can readily identify with that”.

The parrots obviously need this ability to be able to survive in their natural environment.

“However”, says Dr. Auguste von Bayern, leader of the research team: “because parrots are so difficult to study in the wild, we have until now known very little about the challenges they face, for example, where they should search for food and how long they should spend at a given food source”.