Red-Throated Diver Life Cycle: Nest Building To Fledging (and everything in between)

The Red-Throated Diver or Red-Throated Loon as it is known in North America is the smallest species of diver found breeding in the UK. They typically only breed in the far north of Scotland but can often be seen offshore all around the UK coasts during winter.

In Scotland the Red-Throated Diver has the nickname of the “Rain Goose” because it is believed that it can predict the weather. Apparently if the Red-Throated Diver makes short cries it indicates fine weather and long, plaintive cries indicate bad weather is approaching.

Red-Throated Divers are easily recognised during summer by their grey and brown plumage, up tilted black bill, white underparts, narrow black and white stripes on the back of the neck and characteristic red throat. The plumage of both sexes are the same with males being slightly larger in size than females.

During the non-breeding season Red-Throated Divers have a white face, chin and foreneck, a grey top of the head and back of the neck and dark speckling on their dark mantle. Another striking feature of the Red-Throated Diver is its red eyes.

In this article we’ll be looking at the life cycle of the Red-Throated Diver from nest building to fledging and much more in between. Keep reading to find out more about these fascinating birds.

How Long Does A Red-Throated Diver Live?

In the wild the average age of a Red-Throated Diver is around 5 to 9 years. However, if conditions are right, there’s ample food availability and the birds are fortunate, they can live much longer.

There are records of one individual surviving for almost 36 years according to ring data.

How Fast Can A Red-Throated Diver Fly?

The Red-Throated Diver is a strong flyer and has been recorded flying at speeds of up to 47 to 48 mph (75 to 78 km/h). However, like all members of the Loon family, the Red-Throated Diver goes through a wing moult which makes it lose all of its flight feathers.

This renders the Red-Throated Diver flightless for around 3 to 4 weeks. Most members of the Loon family go through the moult in late winter, but the Red-Throated Diver loses its flight ability during late summer or early autumn.

Are Red-Throated Divers Aggressive?

Like many birds, the Red-Throated Diver can become aggressive during the breeding season. They display aggressive posturing during their courtship rituals and maintain this aggressive stance all through the breeding cycle.

If aggressive displays don’t deter their opponent, Red-Throated Divers will dive and poke their opponent in the belly area with their sharp, pointed bills.

Once the breeding season is over, Red-Throated Divers are often found in large flocks at feeding areas. There might be the odd aggressive behaviour but it’s never as serious as it is during the breeding season.

What Is A Red-Throated Diver’s Habitat?

The Red-Throated Diver has different habitats depending on the time of year. During the breeding season, they are typically found in freshwater habitats, including small lakes, ponds, and bogs, often in tundra and taiga regions. These bodies of water are usually shallow and may be close to the coast.

Red-Throated Divers breed in northern parts of North America. Europe and Asia. In the UK they only breed in the far north of Scotland.

In winter, they migrate to coastal regions further south and will be found in marine environments, typically sheltered coastal waters like bays, estuaries and inlets. They can also be spotted in deeper offshore waters.

How Long Does It Take For A Red-Throated Diver To Build A Nest?

Red-Throated Divers make simple scrape nests on the ground close to water. Due to the simple design of the nest it typically takes no longer than a few days at most to construct it.

They typically make their nests close to the water’s edge, often on small islands, in marshy areas or even on floating mats of vegetation. The nest is a simple depression and can be lined with localised vegetation, mud or other localised materials or, in some cases, the eggs are laid directly on the ground.

Red-Throated Divers tend to make functional nests rather than elaborate ones.

Eggs

Once the pair are happy with their nest construction, the female will lay her eggs and we move onto the next stage in the life cycle of the Red-Throated Diver, egg rearing.

When Do Red-Throated Divers Lay Eggs?

They typically lay their eggs from late May to early June although they are often in the breeding areas way before this time. Red-Throated Divers typically arrive in northern Scotland’s coastal areas from around mid February and start to visit breeding lakes from around mid March.

How Many Eggs Does A Red-Throated Diver Lay?

Red-Throated Divers can lay anywhere between 1 to 3 eggs but a typical clutch contains 2 eggs. They only lay one brood per breeding season which ensures that the chicks have a high survival rate.

What Do Red-Throated Diver Eggs Look Like?

Red-Throated Diver eggs are olive-brown in colour and are covered in dark brown or black spots. These markings on the eggs act as a camouflage to protect them from any would-be predators.

Each egg is around 74 x 46 mm in size and weighs around 83 grams with 8% of that weight being the weight of the shell.

How Long Do Red-Throated Diver Eggs Take To Hatch?

The female is responsible for the incubation of the eggs which typically takes anywhere between 26 to 29 days and begins as soon as the first egg has been laid. The male will be close by but doesn’t take much interest in the actual incubating process.

Having said that, he will take over from time to time to relieve the female but she does the majority of caring for the eggs. The eggs hatch asynchronously which means that the first egg laid will hatch before the following egg and so on.

Chicks

Once the eggs hatch, we move onto the next important stage in the life cycle of the Red-Throated Diver, the chick rearing stage.

How Many Chicks Does A Red-Throated Diver Have?

The number of chicks usually corresponds to the number of eggs laid. The parents typically have 2 chicks from the same number of eggs laid.

However, adverse weather conditions and a lack of attention from the female can lead to less than perfect results. Having said that, in most cases each nest produces 1 or 2 chicks.

When Do Red-Throated Diver Chicks Open Their Eyes?

Red-Throated Diver chicks hatch with their eyes open. These precocial chicks are covered in downy feathers and able to walk as soon as they hatch. Their parents will feed them small aquatic invertebrates at first and then small fish for around 38 to 48 days.

When Do Red-Throated Diver Chicks Fledge?

The young chicks develop as they grow and feed on their protein rich diet. They typically take their first flight or fledge around 47 to 54 days after hatching.

Shortly after fledging, it is time for Red-Throated Divers to migrate to warmer southern areas to overwinter.

SEE ALSO: Pochard Life Cycle: Nest Building To Fledging (and everything in between)

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