The Puffin’s (Disposable) Beak
What is the puffin’s most striking feature? Surely it must be its large, brightly coloured beak. The bird not only uses it to catch fish, it can also impress the opposite sex and use it to cool off its body. So what if it doesn’t need these features for a while? The answer is simply to shed part of its beak.
Puffins have been called the clowns among sea birds. This nickname comes from their large, deep orange beak with touches of bluish-grey and yellow. Puffins not only impress the many tourists trying to spot them along the coasts of Iceland, Scotland or Norway, but they are hoping to impress a mate as well. The bright colours attract attention and make it clear that this puffin is ready to start a family.
Grey winter
When temperatures drop, the puffin prepares for winter by shedding the outer part of its beak. Goodbye bright orange! Until the start of the next breeding season, the puffin has a smaller, greyer beak.
Fluorescent beak
In addition to these striking colours, researchers have also discovered that puffin beaks light up under UV light. Why do they have a fluorescent beak? Perhaps this also helps them to find a suitable partner. After all, unlike humans, these sea birds can see UV light.
The right temperature
All this is remarkable, but the puffin's beak has one more special feature. It can act as an air conditioner. That is what biologists concluded in 2019 when they used an infrared camera to take images of crested puffins resting after a flight. The bird produces an enormous amount of heat during these flights. His wide beak allows him to get rid of the heat. On the infrared images, which were taken every two minutes, the researchers could see the gradual fall in the temperature of the beak.
Only benefits
The particular characteristics of a puffin’s beak may explain why puffins do not conform to the general evolutionary principle that applies to birds: the colder the climate, the smaller the beak. After all, a puffin would be crazy to go for less beak. His large, conspicuous beak helps him to catch more fish, charm a mate, ánd cool off. That's a real evolutionary advantage.
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