Highly sensitive beaks could help albatrosses and penguins find food

Researchers have discovered that seabirds, including penguins and albatrosses, have highly sensitive areas in their beaks that could help them find food. This is the first time this ability has been identified in seabirds.

An international team of researchers, led by the University of Cambridge, studied more than 350 species of modern birds and found that seabirds have a high density of sensory receptors and nerves at the tips of their beaks, something previously identified in specialist tactile foragers such as ducks.

The researchers say this touch-sensitive region may have come from a common ancestor, and more work is needed to determine whether it serves a specific function in modern birds. Further study of their beaks and foraging behavior could help preserve some of these birds, many of which are threatened with extinction. The findings are published in the journal Biology letters.

In the same way that humans and other primates use their hands, birds use their beaks to interact with the world around them. Some birds have specialized tactile areas on the tips of their beaks to help them find food, but because this ability has not been widely studied, it is unclear how the phenomenon evolved or how widespread it is.

“Many scientists thought that most birds had touch-sensitive beaks, but we hadn’t studied this enough to know whether this was a common ability or whether it was limited to certain bird families,” said lead author Dr Carla du Toit, from Cambridge’s Department of Earth Sciences.

One poorly studied group of seabirds is the Austrodyptornithes, which includes albatrosses, petrels, and penguins. Since many species of birds in this group are critically endangered, understanding how they find food using their beaks could be a valuable tool to help their conservation.

Du Toit and colleagues from the UK and South Africa conducted a study of 361 species of modern birds, based on fossils and skeletons, as well as birds accidentally killed by fishing lines and nets. The team focused on the birds’ beaks, how they are constructed and how they connect to their nerves and blood vessels.

The researchers found that albatrosses and penguins have organs with high density of sensory receptors and high concentrations of nerves in their beaks, which is more common in animals that specialize in hunting for food, such as ducks. This is the first time this feature has been observed in seabirds.

“Seabirds are not known to be tactile hunter-gatherers, so it’s surprising to discover that they have this organ,” du Toit said. “It’s really exciting to be the first to see something.”

These touch-sensitive beaks could help seabirds find food at night or underwater, as they could allow them to detect tiny vibrations from potential prey. Some birds already known to have touch-sensitive beaks use them to detect tiny vibrations underground from worms, for example.

However, these touch-sensitive areas could also be a “remnant” of a common ancestor that has no specific function in modern birds, such as the beaks of ostriches and emus. Further studies in living birds will be needed to establish the exact function of these touch-sensitive areas, which could also help determine how this ability evolved.

“In humans and other primates, our sensitive hands and fingers have allowed us to master a wide variety of environments,” du Toit said. “Beaks are sort of analogous to hands, but this is the first time we’ve seen touch-sensitive beaks in seabirds. It’s remarkable that no one has ever really studied this in detail, given that we all learn about evolution from the beaks of Darwin’s finches in school.”

The researchers say their findings could potentially play a role in the conservation of some of these birds. Of the 22 known albatross species, 15 are threatened with extinction and two are listed as critically endangered.

One of the biggest threats to albatrosses is commercial longline fishing, which kills about 100,000 birds a year when they get tangled in lines and drown. Du Toit says if scientists can better understand how these birds get their food, it could help protect them.

“There is still a lot of work to be done, but if albatrosses and other seabirds are able to detect the vibrations of their potential prey via their beaks, it might be possible to attach some sort of device to longlines that could repel them, so they are less likely to get caught,” du Toit said.

“Of course, the biggest threats to birds like albatrosses are climate change, rising ocean temperatures, plastic pollution and declining fish stocks, but if there is a way to reduce the risks to seabirds, even in a small way, then that is incredibly valuable. They are such special birds and I have been interested in them for as long as I can remember.”