Guillemot

Guillemots are a group of seabirds belonging to the Alcidae family. They are part of the order Charadriiformes. In Europe, the term guillemot describes two different genera: Uria and Cepphus.

In North America, the name is used differently. People there call the Uria species "murres." Only the Cepphus species are called guillemots in North America. These birds are known for forming very dense colonies on cliffs during their reproductive season. These large groups help protect the birds and their offspring from predators like gulls.

The Uria genus contains two living species. These are the common murre (Uria aalge) and the thick-billed murre (Uria lomvia). The Uria species are also closely related to the razorbill, the little auk, and the extinct great auk. These birds belong to a tribe called Alcini. You can identify Uria species by their white bellies. They also have thicker and longer bills than the Cepphus genus.

The Cepphus genus is different. It includes the black guillemot, the pigeon guillemot, and the spectacled guillemot. These birds belong to the tribe Cepphini. They are smaller than the Uria species. They have rounder heads, bright red feet, and black bellies during the breeding season.

Guillemots have a unique way of laying eggs. They do not build nests out of sticks or grass. Instead, they lay a single pyriform egg directly on a cliff edge. Pyriform means the egg is shaped like a pear.

This shape is very important for survival on steep cliffs. One side of the egg is long and straight. Ornithologist Tim Birkhead studied how these eggs stay stable. He found that the long, straight edge rests on the ground. This creates more friction, which is a force that resists movement. This friction makes the egg less likely to roll off the ledge. While some thought the egg might roll in a protective arc, Birkhead found the arc is actually wider than most ledges. This means the pear shape is vital for keeping the egg from falling.

The history of the name guillemot is quite interesting. The spelling comes from French. It was first recorded by Pierre Belon in 1555. The name is actually onomatopoeic. This means the word sounds like a noise. It comes from the loud, high-pitched "will, willem" begging calls made by young birds.

The American name, murre, is also onomatopoeic. It mimics the growling call that adult common guillemots make. This shows how much scientists and observers listen to the birds to understand them.

Human history is also connected to these birds. In Scotland, people used to collect guillemot eggs from the St Kilda islands. Men would scale the high cliffs to reach them. These eggs were collected until the late 1920s. People would bury the eggs in peat ash to protect them from the cold northern winters. They believed the eggs were similar to duck eggs in both nutrition and taste. The eggs are quite large, often representing about 11% of the female's total body weight. Because they are colorful and large, they were very attractive to collectors.

Guillemot chicks face a dangerous journey as they grow. They are born on rocky cliffs near the sea. Before their wings are strong enough for flight, they must leave the cliff. They do not fly down; instead, they jump.

They essentially parachute toward the ground. To survive this fall, they rely on their physical traits. They have very dense, downy feathers. Their wings are also underdeveloped at this stage. This combination of thick feathers and weak wings allows them to avoid serious harm. In fact, they can sometimes bounce slightly when they hit the ground.

Scientists have also found fossils of these birds from the past. There are prehistoric species of Uria, such as Uria brodkorbi from the Late Miocene. There are also fossils of Cepphus from the Late Miocene and the Pliocene. These fossils help us understand how these seabirds have changed over millions of years. By studying both living birds and ancient fossils, we can see how the Alcidae family fits into the wider history of life on Earth.