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Black Guillemot

November 15, 2023

Welcome to our educational blog dedicated to the fascinating Black Guillemot, a seabird known for its striking appearance and unique behaviors. In this blog, we will explore various aspects of this captivating bird species, such as its size and shape, color pattern, behavior, habitat, and ecosystem services. We'll also share some interesting facts that make the Black Guillemot stand out among other seabirds. So, let's dive into the world of the Black Guillemot and discover what makes this bird so special.


Size and Shape

The Black Guillemot is a medium-sized seabird belonging to the auk family. It measures between 12 to 14 inches in length, with a wingspan of approximately 22 inches, and weighs around 17 to 22 ounces. Males and females are similar in size and shape.

The Black Guillemot has a stocky build, with a relatively large head, short neck, and short, rounded wings. Its bill is thin, straight, and pointed, with a small hook at the tip that aids in catching and holding prey. The legs and feet are set far back on the body, which helps the bird propel itself underwater while swimming, but makes it rather awkward on land.


Color Pattern

The Black Guillemot is known for its striking color pattern. During the breeding season, adults sport a jet-black plumage with white wing patches that are visible when the wings are folded or in flight. The legs and feet are bright red, adding a splash of color to their appearance.

Outside the breeding season, the Black Guillemot's plumage transforms into a mottled grey and white pattern, giving it a more subdued appearance. However, the white wing patches and red legs and feet remain prominent throughout the year. Juvenile Black Guillemots resemble the non-breeding adults, but they have a more uniform greyish-brown plumage.



Black Guillemots are social birds, often seen in small groups, especially during the breeding season. They are excellent swimmers and divers, using their wings to propel themselves underwater in pursuit of their prey. Their diet primarily consists of fish and invertebrates such as crustaceans and mollusks.

During the breeding season, Black Guillemots form monogamous pairs and nest in rocky crevices, abandoned burrows, or other sheltered locations along the coast. Both parents share in the incubation and chick-rearing duties. Once the chicks fledge, the family group remains together for a short period before dispersing.

The Black Guillemot's vocalizations are quite distinctive, often described as high-pitched, musical whistles or trills. These calls are used to maintain contact with mates or other group members, and also play a role in territorial and courtship displays.



Black Guillemots are found in the cold waters of the North Atlantic and Arctic Oceans. They inhabit rocky coastlines, cliffs, and offshore islands, and are closely associated with the marine environment throughout the year. In winter, they can be found in areas with open water or partially ice-covered seas, often venturing further north than other members of the auk family.

These birds have a strong preference for shallow waters close to the shore, where they forage for food. They are particularly adapted to life in the harsh Arctic environment and can withstand extremely cold temperatures and stormy conditions.



  1. Black Guillemots are one of the few members of the auk family that can be found in both the Arctic and sub-Arctic regions, making them highly adaptable to a wide range of environmental conditions.
  2. Unlike most seabirds, Black Guillemots can take off from the water without needing a running start. They accomplish this by vigorously flapping their wings and "pattering" their feet on the water's surface.
  3. Black Guillemots have a unique method of catching fish – they use their wings to "fly" underwater, propelling themselves toward their prey with incredible speed and agility.
  4. In some areas, Black Guillemots have been observed using tools, such as small sticks or pebbles, to dislodge prey from crevices – a rare behavior among birds.
  5. The Black Guillemot is one of the few bird species in which both parents share equally in the incubation and chick-rearing duties, ensuring a strong bond between the pair and a higher chance of survival for their offspring.


Ecosystem Services

Black Guillemots play an essential role in their ecosystem by serving as both predator and prey. As predators, they help control fish and invertebrate populations, maintaining a balanced marine ecosystem. They are also a vital food source for larger predators, such as birds of prey, seals, and even polar bears.

Their nesting habits in rocky crevices and burrows help to aerate the soil and promote the growth of vegetation in coastal areas. Additionally, their guano (droppings) provides valuable nutrients to the soil, contributing to the overall health and productivity of their habitat.

As a seabird species dependent on healthy marine ecosystems, the Black Guillemot can also act as an indicator of environmental health. Changes in their population size or distribution may signal shifts in ocean conditions or the availability of their prey species.



The Black Guillemot is a remarkable seabird that showcases incredible adaptability and resilience in the face of harsh environments. Its striking color pattern, unique behaviors, and vital role in maintaining the balance of marine ecosystems make it a fascinating subject of study for bird enthusiasts and researchers alike. As we continue to learn more about this captivating bird, it's essential to conserve and protect its habitat to ensure the survival of the Black Guillemot for generations to come.