Corncrake Life Cycle: Nest Building To Fledging (and everything in between)
The Corncrake (Crex crex) is a bird of mystery for many due to its secretive nature and elusive behaviour. Known more for its distinctive “crex-crex” call than its appearance, this bird can be found in the UK during the summer, particularly in Scotland’s meadows and hayfields.
Despite being notoriously difficult to spot, Corncrakes have a fascinating life cycle, from building nests hidden in tall grasses to nurturing their chicks until they are ready to fledge.
In this article, we will have a closer look into their life cycle, exploring every stage from nest building to the moment their chicks take their first flight!
Table of Contents
How Long Does A Corncrake Live?
Corncrakes typically live for 2 to 3 years in the wild, though some individuals can survive up to 5 to 7 years under favourable conditions.
Their relatively short lifespan is influenced by various challenges they face, including predation and habitat loss. During their annual migration between the UK and sub-Saharan Africa, they face numerous hazards that can impact their survival rates.
Despite their relatively brief lives, Corncrakes are highly productive breeders, which helps maintain their populations when conditions are favourable. Their ability to produce multiple broods in a single season is crucial for their survival as a species.
How Fast Can A Corncrake Fly?
Corncrakes can fly at speeds of approximately 20 to 25 miles per hour (32-40 km/h). While they are capable flyers, they prefer to remain hidden in vegetation and typically only take to the air when absolutely necessary.
When they do fly, their flight appears rather weak and laboured, with their legs dangling. However, this seemingly awkward flight ability doesn’t prevent them from completing their impressive long-distance migrations between the UK and Africa.
These birds are actually much more proficient at running through dense vegetation, where they can move quickly and silently, making them extremely difficult to spot.
Are Corncrakes Aggressive?
Corncrakes are generally not aggressive birds. They are shy and secretive, preferring to remain hidden in tall grasses.
However, during the breeding season, male Corncrakes may display some territorial behaviour, particularly when it comes to competing for mates. The primary form of aggression is through their loud, repetitive call, used to ward off other males. Physical aggression between Corncrakes is rare, as they prefer to rely on their vocal prowess to maintain territory and attract a mate.
Outside of the breeding season, Corncrakes are solitary and non-confrontational birds. Their focus is primarily on feeding and staying out of sight. Interestingly, male Corncrakes sometimes move between territories in search of females, but even this is done with minimal aggression.
What Is A Corncrake’s Habitat?
Corncrakes prefer open, grassy habitats with plenty of tall vegetation for cover.
In the UK, they are typically found in meadows and hayfields, especially those managed through traditional agricultural practices that favour biodiversity. This preference for tall grasses makes them difficult to spot, but it also offers them protection from predators.
The ideal Corncrake habitat includes areas where vegetation grows tall enough to provide cover from predators while allowing easy movement at ground level. They show a particular preference for spots with mixed vegetation types and traditional farming practices.
How Long Does It Take For A Corncrake To Build A Nest?
A Corncrake typically takes 2 to 5 days to build its nest. The nest construction is relatively simple compared to many other bird species, reflecting their ground-nesting nature.
The female is responsible for nest building, creating a shallow scrape in the ground which she lines with dry grass and leaves. The nest is usually well-hidden in tall vegetation, providing protection from predators.
The quick nest-building process allows females to rapidly establish new nesting sites, which is particularly important as they often produce second clutches while their first brood is still dependent on them.
Eggs
The egg-laying phase is a crucial period in the Corncrake’s breeding cycle, with unique adaptations that help ensure successful reproduction.
When Do Corncrakes Lay Eggs?
Corncrakes typically lay eggs between May and July in the UK. This timing coincides with the growth of vegetation that provides essential cover for their nests.
The laying period may vary depending on when the birds arrive from their migration and local weather conditions. Some females may produce a second clutch as late as August, particularly if conditions are favourable.
How Many Eggs Does A Corncrake Lay?
A Corncrake typically lays between 8 to 12 eggs per clutch. They are one of the more productive members of the rail family in terms of clutch size.
Females may produce two clutches in a season, potentially laying up to 24 eggs in total. This high reproductive rate helps offset the various challenges these birds face, from predation to habitat loss.
The female will lay one egg per day until the clutch is complete, though incubation typically begins before all eggs are laid.
What Do Corncrake Eggs Look Like?
Corncrake eggs are oval-shaped and measure approximately 37mm x 26mm. They have a creamy-white or buff background colour with reddish-brown speckles and blotches.
The markings on the eggs can vary in intensity and distribution, but they typically provide good camouflage when nested among dead vegetation. The shell is smooth but not glossy, with a slightly thick texture that helps protect the developing chick.
Each egg weighs about 13 to 19 grams, which is relatively large for a bird of this size, providing the developing chicks with good reserves for their rapid early growth.
How Long Do Corncrake Eggs Take To Hatch?
Corncrake eggs typically take 16 to 19 days to hatch. The female alone incubates the eggs, taking short breaks to feed.
During incubation, the female sits tightly on the nest, relying on her camouflaged plumage to avoid detection. The eggs don’t all hatch simultaneously, but usually within a 24 to 48 hour period.
Chicks
Corncrake chicks develop rapidly, an adaptation that helps them survive in their vulnerable ground-dwelling environment.
How Many Chicks Does A Corncrake Have?
A Corncrake typically raises 8 to 12 chicks per brood, though not all eggs may hatch successfully. With the possibility of two broods per season, a single female might raise up to 20 chicks in a good year.
Survival rates vary significantly depending on factors such as weather conditions, predation pressure, and habitat quality. The ability to produce multiple large broods helps offset the various challenges these chicks face.
When Do Corncrake Chicks Open Their Eyes?
Corncrake chicks are precocial, meaning they hatch with their eyes open and are able to leave the nest within 24 hours of hatching.
This rapid development is crucial for their survival strategy. Being able to see and move immediately after hatching allows them to follow their mother and find food independently, though they still rely on her for protection and guidance.
When Do Corncrake Chicks Fledge?
Corncrake chicks become capable of short flights at around 34 to 38 days old. However, they are able to leave the nest and follow their mother within 24 hours of hatching.
The chicks develop quickly, becoming independent at about 2 to 3 weeks of age. This rapid development is essential for their survival, particularly in agricultural landscapes where hay cutting could disrupt their development.
The young birds continue to develop their flying abilities over several weeks, though like their parents, they prefer to run and hide rather than fly when disturbed.
SEE ALSO: Corncrake Diet and Size: Feeding Habits, Predators, and Measurements
Frequently Asked Questions
Corncrakes are omnivorous birds, primarily feeding on insects, worms, spiders, and seeds. Their diet varies depending on the availability of food in their habitat, with a greater emphasis on invertebrates during the breeding season.
Corncrakes can be found in the western and northern islands of Scotland during the summer months, particularly in areas with traditional hay meadows and dense grassy cover.
Yes, Corncrakes are migratory birds. They breed in the UK during the summer and migrate to Africa for the winter, undertaking long-distance flights to reach their wintering grounds.
