Do birds enjoy flying?

Who hasn’t dreamed of flying like a bird? But do birds actually enjoy flying as much as we imagine? A new study by researchers at Utrecht University shows that galahs, Australian cockatoos, almost always choose to fly when given the opportunity. And after several days of flying, the birds make more optimistic choices. These findings suggest that flying leads to positive emotions in the cockatoos. The study was conducted at Vogelpark Avifauna and was recently published in the scientific journal Behaviour.

“Birds often fly without an obvious purpose. Whether they do this because they enjoy flying is something I have wondered about my entire life,” says behavioural biologist Jorg Massen. “Now, we finally had the tools and conditions to study this in a controlled way.”

Measuring instead of asking

Massen has been researching emotions in animals for some time now. “It has always been challenging to demonstrate emotions in animals,” he says. “You can’t simply ask them how they feel.”

However, a relatively new approach makes it possible to gain insight into animal emotions. This approach is based on research on people, which has identified the effects emotions have on people and how they can be measured without directly asking questions.

The findings from these three perspectives together provide a fairly convincing answer to the question of whether an animal has emotions. Whether animals actually experience those emotions, in other words, whether they have feelings, is a more difficult question to answer.

“When people experience emotions, their responses change. For example, they may become more optimistic or, conversely, more pessimistic. They also display different behaviour and react physiologically to emotions, for example by producing certain hormones,” explains Massen.

Flying voluntarily

During spring season, Massen and his colleagues gave seventeen galahs at Avifauna several opportunities to voluntarily take part in a flight demonstration. Almost without exception, the birds chose to participate every time. After the flights, the researchers observed the birds, conducted a test to measure their level of optimism, and collected droppings to analyse a breakdown product of corticosterone, the avian equivalent of the stress hormone cortisol. By combining these three methods, Massen and his colleagues sought to determine whether the birds enjoy flying.

More optimistic

The observations revealed, among other things, that the cockatoos, which had just eaten and were therefore not hungry, engaged in more foraging behaviour after flying. “This is a very natural behaviour that animals show when they feel at ease,” says Massen.

The researchers also observed that the birds became more optimistic after several days of flying, whereas they became increasingly pessimistic the longer they were unable to fly.

As a child, you sometimes ask yourself questions that you cannot answer straight away. Stay curious and keep those questions in the back of your mind.

Analysis of the substance in the animals’ faeces did not reveal a clear effect. “We expected flying to reduce stress and, as a result, to reduce the level of this breakdown product in the faeces,” explains Massen. “However, physical stress, such as that caused by flying, also increases levels of this substance. In hindsight, it may not have been the ideal measure to use. Unfortunately, not all hormones can be measured equally reliably in faeces, and we prefer to avoid invasive methods such as taking blood samples.”

By combining the results, the researchers conclude that flying leads to positive emotions in the cockatoos. “The findings from these three perspectives together provide a fairly convincing answer to the question of whether an animal has emotions,” says Massen. “Whether animals actually experience those emotions, in other words, whether they have feelings, is a more difficult question to answer.”

Other bird species

Massen emphasises that this study is only a first step in research into flight and emotions. “It shows that we need to think carefully about how aviaries can provide birds with enough space to fly. Of course, we are not saying anything new here, but it is always valuable to support these ideas with scientific evidence. And it is important to also conduct this research in other bird species, particularly species from different groups with different ecological niches. I can imagine, for example, that birds of prey, which primarily need to conserve energy, mainly fly to locate and catch prey, and that flying may not provide them with additional benefits.”

Born out of curiosity

Two of the authors of the study, Kate Malone and Roos de Vries, worked on the study while they were still biology students. “Roos now works for the Dutch Society for the Protection of Birds, while Kate now works in the bird department of EAZA, the umbrella organisation for European zoos,” says Massen. “I’m very pleased to see them continuing in this field and taking on important roles.”

Massen would also like to share some advice with other (young) researchers. “This research was driven by curiosity. As a child, you sometimes ask yourself questions that you cannot answer straight away. Stay curious and keep those questions in the back of your mind. You may well get the chance to answer them later in life.”