Stone-Curlew Diet and Size: Feeding Habits, Predators, and Measurements
Stone-curlews, also known as Eurasian thick-knees, are fascinating birds known for their distinctive calls and cryptic plumage.
These nocturnal birds are part of the Burhinidae family and can be found in dry, open habitats such as grasslands, heathlands, and sandy areas.
In this article, we will explore the diet and size of stone-curlews, delving into their feeding habits, predators, and measurements.
Table of Contents
The Dietary Habits Of The Stone-Curlew
The Stone-Curlew has a varied diet that reflects its adaptability to different habitats and food sources. Let’s take a closer look at what these birds eat and how they feed their young.
What Does A Stone-Curlew Eat?
Stone-Curlews primarily feed on insects and other invertebrates. Their diet consists mainly of beetles, earwigs, caterpillars, and worms. They are particularly fond of large insects like dor beetles and mole crickets.
In addition to insects, Stone-Curlews also consume small vertebrates such as lizards, frogs, and occasionally small rats.
These birds are primarily nocturnal feeders, using their large eyes to spot prey in low light conditions. They hunt by walking slowly and deliberately, pausing frequently to listen and look for potential food items. When prey is detected, the Stone-Curlew will quickly snatch it up with its strong beak.
During the day, Stone-Curlews often remain motionless, relying on their camouflage to blend in with their surroundings. This behaviour not only helps them avoid predators but also conserves energy for their nighttime foraging activities.
What To Feed A Baby Stone-Curlew?
Baby Stone-Curlews, known as chicks, are precocial, meaning they are relatively mature and mobile from the moment they hatch.
Chicks rely heavily on their parents for food during the first few weeks of life. Parents are observed to directly feed their chicks with food by mouth, which makes it easier for the chicks to consume and digest.
As they grow older, the chicks begin to forage alongside their parents, learning essential hunting and feeding skills.
Breeding Habits Of Stone-Curlews
Stone-Curlews have interesting breeding behaviours that are well-adapted to their open habitat preferences. They typically breed in areas with short, sparse vegetation and stony or sandy soils, which provide excellent camouflage for both adults and eggs.
In the UK, Stone-Curlews usually arrive at their breeding grounds in March or April. They create a simple nest, which is nothing more than a shallow scrape in the ground. The female typically lays two eggs, which are incubated by both parents for about 24 to 26 days.
Do Stone-Curlews Mate For Life?
Stone-curlews do not necessarily mate for life, but they often form strong pair bonds during the breeding season. These bonds may last for several seasons, with pairs returning to the same breeding sites year after year.
Both parents are involved in incubating the eggs and caring for the chicks, which enhances the survival rate of their offspring.
During courtship, males perform elaborate displays that include calling, spreading their wings, and bowing to attract females.
The Size & Weight Of Stone-Curlews
Stone-curlews are medium-sized birds with distinctive physical characteristics that aid in their survival and adaptability in various habitats. Understanding their size and weight helps in identifying and studying these birds in the wild.
How Much Does A Stone-Curlew Weigh?
Adult stone-curlews typically weigh between 430 to 500 grams. This weight range allows them to be agile on the ground and efficient in their hunting techniques.
The weight of Stone-Curlews can fluctuate throughout the year, with birds often being heavier before migration as they build up fat reserves for their long journeys.
During the breeding season, weights may be slightly lower as the birds expend energy on territory defence, egg-laying, and caring for chicks.
How Big Is A Stone-Curlew?
Stone-Curlews are medium-sized birds, with a body length ranging from 40 to 44 centimetres. They have a wingspan of approximately 77 to 85 centimetres, which allows for efficient flight during migration and when evading predators.
One of the most distinctive features of the Stone-Curlew is its large, yellow eyes, which are adapted for nocturnal vision. These eyes, combined with their cryptic plumage and habit of remaining still during the day, make them well-suited for their ground-dwelling lifestyle in open habitats.
Are Stone-Curlews Under Threat?
Stone-Curlews have faced significant challenges in recent decades, particularly in the UK. While not globally threatened, they are considered an Amber List species, and are a Least Concern in the IUCN Red List of Threatened Species.
What Eats A Stone-Curlew?
Stone-Curlews face various predators throughout their life cycle. As ground-nesting birds, their eggs and chicks are particularly vulnerable. Common predators of Stone-Curlew eggs and young include foxes, badgers, and corvids such as crows and magpies.
Adult Stone-Curlews are less vulnerable due to their cryptic coloration and vigilant behaviour. However, they can fall prey to larger birds of prey such as eagles and owls, especially during migration when they may be more exposed.
Human activities, while not direct predation, can also pose significant threats to Stone-Curlews. Disturbance at breeding sites, habitat loss, and collisions with vehicles are all potential dangers that these birds face in modern landscapes.
Where Can I See Stone-Curlews In The UK?
In the UK, Stone-Curlews are primarily found in two main areas: the Breckland region of Norfolk and Suffolk, and the chalk downlands of southern England, particularly in Wiltshire, Hampshire, and Dorset.
One of the best places to try and spot Stone-Curlews includes the Salisbury Plain in Wiltshire, where a significant population breeds.
SEE ALSO: Stone-Curlew Life Cycle: Nest Building To Fledging (and everything in between)
Frequently Asked Questions
The alternative name ‘Thick-knee’ refers to the bird’s prominent knee joints, which appear swollen or thick. This feature is actually an adaptation that allows for better shock absorption when running, which is important for a ground-dwelling bird.
Yes, Stone-Curlews are migratory birds. In the UK, they are summer visitors, arriving in March or April and departing for warmer climates in August or September.
Stone-Curlews can live up to 10 years in the wild, although the average lifespan is typically shorter due to various environmental factors and predation risks.
Stone-curlews are known for their loud, eerie calls, which they use to communicate with each other, especially during the breeding season. These calls can be heard at night and are often described as haunting and melodious.
