Razorbill Life Cycle: Nest Building To Fledging (and everything in between)
Razorbills, Razor-Billed Auks or Lesser Auks as they’re also known are medium sized seabirds which are black on top, white underneath with a short, thick black bill that has white lines across the end. During winter months, Razorbills have white faces.
Quite a large part of the Razorbill population breeds here in the UK and Ireland. This makes the UK an important part in the conservation of these birds.
In this article we’ll take a look at the life cycle of the Razorbill from nest building to fledging and much more besides. Keep reading to find out more.
Table of Contents
How Long Does A Razorbill Live?
The typical lifespan of the Razorbill is around 13 years and they generally reach sexual maturity at around the age of 4 years. There have been recorded cases of individual Razorbills living to far greater than the average lifespan.
According to ring data, one Razorbill survived for almost 42 years (41 years, 11 months and 23 days).
How Fast Can A Razorbill Fly?
Razorbills can reach a top speed of around 55 mph (88 km/h) or around 24.5 metres per second. Considering their relatively small size and small wings, these speeds are impressive.
They rely on their fast flight speed in order to catch fish and escape from predators. Razorbills are under threat of predation by polar bears, Great Black-Backed Gulls, Peregrine Falcons, Ravens, Jackdaws and Crows to name but a few.
Are Razorbills Aggressive?
Although not known for their aggression, Razorbills can become territorially aggressive during the breeding season. Often engaging in bill fencing displays with other males while calling loudly. They lunge, peck and eventually chase the intruder away.
Female Razorbills will also aggressively knock their mate off other females if they attempt to copulate. They then proceed to chase the offending female away.
They are generally more interested in foraging for food, and looking after their eggs and chicks. But will become aggressive if the need arises particularly around the nesting site.
What Is A Razorbill’s Habitat?
Razorbills live mainly in open seas and spend most of their lives out at sea. They can often be spotted on offshore shoals or ledges and they tend to feed in cold waters with a temperature of below 15 C (59 F).
They breed in colonies on rocky coastlines, cliffs and islands. Their natural habitat is distributed across sub-Arctic and boreal waters of the Atlantic Ocean. With Razorbill populations breeding in eastern North America, western Europe, North west Russia, northern France and the UK.
How Long Does It Take For A Razorbill To Build A Nest?
Razorbills don’t build nests in the traditional sense, they lay their single egg on bare rock or in small crevices on cliffs or narrow ledges. They select a site that offers some protection from bad weather and predatory attacks.
They will sometimes collect small stones, dried droppings, lichen or other plant materials and place them in the area where they will lay their egg.
Selecting the site to lay the egg will take up the most time and can take anywhere between 1 to 3 or 4 days. Once the site has been selected, the pair will often return to the same site every year to lay their egg.
Eggs
Once they are satisfied with the area for laying their egg, Razorbills move on to the next stage in their life cycle, which is laying an egg and rearing a new life.
When Do Razorbills Lay Eggs?
Razorbills typically arrive at their breeding colonies around the end of January and begin breeding in April. They generally lay their eggs from early May onwards.
However, if they are in a breeding colony which is further north and the temperatures are colder, they may not begin egg laying until later in June or even July.
How Many Eggs Does A Razorbill Lay?
The female Razorbill will lay one egg per season. Before laying their egg around 50% of breeding females will leave their mate and copulate with a different male.
They then come back and copulate with their partner. When the male is incubating the egg, the female will leave him again to copulate with different partners. Before returning to the nest to help in the incubation of their egg.
With only one egg to care for Razorbills increase their chances of bringing a new chick to the fledgling stage.
What Do Razorbill Eggs Look Like?
The egg is an ovoid-pyramidal shape, cream coloured with dark brown spots or speckles. It is around 75 x 48 mm in size and weighs around 90 grams.
This special pointed shape prevents it from rolling off the cliff face or ledge.
How Long Do Razorbill Eggs Take To Hatch?
The incubation period generally starts around 48 hours after the egg has been laid. Both partners take turns incubating the egg ensuring it is regularly turned to allow the embryo to develop correctly.
The incubation lasts for around 35 days before hatching occurs.
Chicks
Once the egg hatches, the next stage in the life cycle of the Razorbill is the development and growth of the chick.
How Many Chicks Does A Razorbill Have?
Razorbills will have one chick per season which corresponds to the number of eggs laid. However, around 30% of all eggs laid are lost each season due mainly to predation often by Herring Gulls.
When Do Razorbill Chicks Open Their Eyes?
Razorbill chicks hatch with their eyes open and covered in downy feathers. These precocial chicks can walk and often swim within hours of hatching. However, for the first 24 to 48 hours, Razorbill chicks spend most of their time under their parents’ wings.
During this time there is always at least one parent at the nest site whilst the other is out at sea collecting food for the chick.
When Do Razorbill Chicks Fledge?
Razorbill chicks typically fledge at some point between 15 to 25 days after hatching. They jump off the cliff face or ledge at around 10 to 15 days of age and their parents follow them into the sea to protect them and teach them how to find food. It’s around 5 to 10 days later that the chicks will take their first true flight.
SEE ALSO: Manx Shearwater Vs Guillemot: Key Differences Explained
Frequently Asked Questions
The average lifespan of a Razorbill is around 13 years but some individuals have survived for more than 41 years according to ring records.
Razorbill eggs are cream coloured with dark brown spots or speckles. They are ovoid-pyramidal shaped which helps prevent them from rolling off cliff edges. Each egg weighs around 90 grams.
Although there are some physical similarities, Razorbills are not related to Penguins. However, they are related to Guillemots and Puffins.
