Penguins and albatrosses have a ‘touch sensor’ in their beak

 Penguins and albatrosses have a ‘touch sensor’ in their beak

When hunting in the dark ocean depths, some seabirds may possess a hidden advantage. A recent study has uncovered a network of touch-sensitive pits, known as a bill-tip organ, inside the beaks of albatrosses and penguins. While birds like parrots and ducks use this organ to manipulate objects and sense movement, its presence in seabirds had never been detected until now.

In birds such as ostriches, the bill-tip organ is an evolutionary remnant. However, researchers now aim to determine whether this organ helps penguins and albatrosses catch prey in deep waters or plays a role in their tactile courtship rituals. As Dr. Carla du Toit, the study’s lead author, explains, this discovery highlights how much remains unknown about the sensory abilities of birds.

“Although research on bill-tip organs began over a century ago, our knowledge of them is still limited,” she says. “We know that many species have this organ, but we don’t fully understand how it evolved.”

“Finding these organs in penguins and albatrosses adds a new piece to the puzzle. Describing them for the first time is an exciting step in understanding bird evolution,” Dr. du Toit adds.

What are bill-tip organs used for? Birds’ beaks serve as more than just mouths—they are a primary tool for experiencing the world. While all birds gain some sensory input through their beaks, some species have developed a heightened sense through the ‘bill-tip organ.’

Parrots use this sense to handle food and other objects, ducks to detect food in the water, and species like kiwis and ibises to sense vibrations from prey hidden underground.

Until recently, no one suspected penguins and albatrosses possessed a bill-tip organ. But this changed when two scientists from the Natural History Museum made a surprising discovery.

"About eight years ago, Dr. Alex Bond and Dr. Steve Portugal noticed unusual structures on the beaks of albatrosses," Carla recalls. "They contacted me and my supervisor, Dr. Susan Cunningham, and we realized they could be the sensory pits of a bill-tip organ."

By scanning samples from penguins and albatrosses, the researchers found structures resembling those seen in species known to have bill-tip organs. This included a high concentration of neurovascular foramina, small bone canals that house nerves.

“This was a completely unexpected finding because penguins and albatrosses aren’t typically thought of as touch-based hunters,” Carla explains. "It’s fascinating to consider what they might use this sense for."

Although these seabirds primarily rely on their vision to locate prey, they lose binocular vision and depth perception at the tip of their beaks when underwater. The bill-tip organ could compensate for this, helping them grab and hold prey at close range.

If penguins and albatrosses do use touch-based hunting, this could influence efforts to protect these endangered species. Longline fisheries pose a major threat, as birds are drawn to baited hooks and become entangled in the lines. Understanding their foraging habits might lead to new tactile deterrents to reduce bird casualties.

“We also know that many of these birds ingest plastic, and it’s possible that tactile stimulation causes them to mistake plastic for food,” Carla adds. "Further research will help us determine if this is the case."