For years we have seriously underestimated the intelligence of seabirds, as a simple experiment with a transparent box, a piece of string and some treats shows.

To determine how intelligent a bird is, the so-called ‘string pull test‘. It is actually very simple: take a transparent box that the birds cannot enter with their legs or beak. Then you put something tasty in it that is attached to a string and can only be removed from the box by pulling the string. At least 90 bird species have already undergone the experiment, which has given them more insight into their cognitive functioning without being aware of it. Remarkably enough, most bird species that are confronted with the transparent box and the string dangling from it can be counted as songbirds and parrot-like birds. Until now, much less or even hardly any attention has been paid to water and sea birds. But a new study, published in the magazine Royal Society Open Science changes that and produces striking results.

test

In the research article, scientists describe how they subjected ring-billed gulls to the ‘string-pull test’. The researchers went to gull colonies in Newfoundland (Canada) and presented breeding gulls with a transparent box containing a small dish on which there was something delicious. The only way the seagulls could obtain the treats was by pulling a string and pulling the dish with the treats out of the box.

104 seagulls

The researchers placed the box of treats at 93 nests and then saw how 104 seagulls tried at least once to remove the treats from the box. 25 percent of them succeeded in doing so at least once. And 21 percent of the ring-billed gulls even succeeded in doing so the first time. According to the researchers, this is the first time that a water bird has passed the horizontal string-pull test (see box).

The string-pull test is regularly used to test the problem-solving ability and thus the intelligence of birds, but also mammals. A vertical arrangement is often used, in which birds have to remove the treats from above from the box by hoisting the string up with the help of their beak and legs. But sometimes a horizontal arrangement is also used, in which the laboratory animals have to remove the treats from the side of the box. This approach is often used, for example, to test mammals. The horizontal arrangement was also chosen when testing the ring-billed gull, because the gulls – unlike parrots and songbirds – would probably have great difficulty with the vertical arrangement, pulling the string between the moments when they use their beaks. pull up with their paws.

Intelligent

The experiments suggest that the gulls – and possibly other seabirds as well – are a lot more intelligent than previously thought. And the researchers therefore argue in favor of subjecting the birds to other (more difficult) tests in the future, in order to gain more insight into their cognitive skills. “Cognition has rarely been studied in this bird group,” the researchers say.

underestimated

That we are now somewhat astonished at the intelligence of these waterfowl has more to do with us than with them; we’ve been too focused on birds – like parrots – which already have a bit of intelligence by nature. And in doing so, we have failed to do justice to seabirds whose intelligence is perhaps a little less obvious. We can blame ourselves for that, because if we had taken the time to look closely at the performance and underlying cognitive abilities of these bird species, we would undoubtedly have put them through cognitive tests much earlier. For example, the researchers point to various behaviors that indicate that waterfowl can think in a problem-solving way. “At least 17 species are known to use bait to catch fish and two other species have been observed using tools to preen their feathers.” And their life history also argues for a decent intelligence. “In general, delayed maturity and longevity allow more time for brain development and those traits have been associated with a more complex brain and cognitive abilities that help long-lived species adapt to a changing environment over time. to fit. Most waterfowl have a slow pace of life; they take years to reach sexual maturity and their lifespan often spans several decades. Social behavior and lifelong monogamy are also commonly associated with higher intelligence, as it requires animals to learn complex social systems and establish long-term relationships with their partners. Since many waterfowl, including gulls, live in colonies and bond with a mate for life, we could also expect them to be quite cognitively advanced.”

And so the surprising results are actually not that surprising at all. At the same time – precisely because we have neglected seabirds in cognitive research for so long – many questions remain. More research among other types of seabirds is therefore urgently needed, according to the researchers. Not only to rectify the fact that we have underestimated seabirds for years, but also because more insight into their cognitive skills can help us to get a better picture of their future. “As speed of innovation and problem-solving ability is associated with greater resilience in times of habitat change, we suggest that testing the problem-solving skills of other species dealing with challenges in their habitat can also tell us how vulnerable they are. in a rapidly changing world.”