Subalpine Warbler
Curruca cantillans
Visual Identification
Appearance
The Subalpine Warbler is a small, elegant bird with distinct sexual dimorphism. Males display a striking blue-grey upper body, contrasting white moustachial stripes, and rich chestnut-red underparts. Their eyes are accentuated by a prominent red eye ring.
Females are more subdued, with brown-grey upperparts and pale buff underparts. Both sexes have dark legs and a fine, pointed black bill. Juveniles resemble females but with duller plumage.
Size
Length
11cm to 12.5cm
Wingspan
15cm to 19cm
Weight
9g to 12g
Habitat and Distribution
Habitats
Woodland
Garden
Wetland
Coastal
Urban
Farmland
Grassland
Desert
Tundra
Rainforest
Mountain
Savanna
Distribution
Subalpine Warblers inhabit Mediterranean scrubland, maquis, and open woodland with dense undergrowth. Their breeding range extends across southern Europe, from Portugal to Greece, including parts of North Africa.
During winter, they migrate to sub-Saharan Africa. Occasional vagrants are spotted in the UK, particularly in spring, making them an exciting find for British birdwatchers.
Elevation Range
Up to 2,200 meters
Climate zones
Mediterranean, Temperate
Distribution Map
This map gives you a rough idea of where you might spot a Subalpine Warbler. The coloured areas show countries where these birds have been seen.
A few things to keep in mind:
- Birds might not be everywhere in the coloured areas, for example, they may be present around the coast of that country
- Where birds live can change with seasons and available food
- This map is quite simple - it doesn't show exact locations
We're working on making our maps even better! Soon, we hope to show you:
- More detailed maps for bigger countries, including state and region
- How birds move around during different seasons
Distribution by Region
Behaviour and Ecology
Bird Attributes
This feature is in beta. We'd love your feedback to improve it!
Share your thoughtsBird Attributes Explained
Our bird attributes system rates various aspects of a bird's capabilities on a scale of 0-100, based on data from field observations, scientific studies, and expert knowledge.
Attribute Categories:
- Agility: Manoeuvrability, speed, and grace in flight or movement.
- Strength: Physical power, often correlating with size and hunting abilities.
- Adaptability: Ability to thrive in various environments or changing conditions.
- Aggressiveness: Territorial behaviour and assertiveness, particularly during breeding seasons.
- Endurance: Stamina, often seen in migration patterns or foraging behaviours.
Understanding the Ratings:
- 0-20: Very Low
- 21-40: Low
- 41-60: Average
- 61-80: High
- 81-100: Very High
Remember, these attributes are relative to other bird species and don't necessarily indicate superiority.
Hover over the icon next to each attribute for more information.
Tap the icon next to each attribute for more information.
Agility
Reflects the bird's manoeuvrability, speed, and grace in flight or movement.
The Subalpine Warbler demonstrates high agility, constantly flitting through dense vegetation and even hovering briefly while foraging. This nimble behaviour is crucial for their insect-hunting lifestyle.
Strength
Indicates the bird's physical power, often correlating with size and hunting abilities.
As one of the smallest warblers in Europe, weighing only 9-12 grams, the Subalpine Warbler has limited physical strength. Their size is adapted for quick movements rather than power.
Adaptability
Represents the bird's ability to thrive in various environments or changing conditions.
These birds show good adaptability, inhabiting various environments from scrubland to open woodland, and adjusting their diet seasonally. Their ability to raise two broods in a season also indicates adaptability to favourable conditions.
Aggressiveness
Measures the bird's territorial behaviour and assertiveness, particularly during breeding seasons.
While not overly aggressive, male Subalpine Warblers become territorial during breeding season, performing display flights and singing persistently to defend their territory and attract mates.
Endurance
Reflects the bird's stamina, often seen in migration patterns or foraging behaviours.
The Subalpine Warbler's long-distance migration from southern Europe to sub-Saharan Africa demonstrates considerable endurance. Their ability to survive up to 7 years in the wild, despite their small size, also suggests good stamina.
Diet
The Subalpine Warbler primarily feeds on small insects and spiders, which it gleans from leaves and branches.
During autumn, they supplement their diet with small berries and fruits, especially before migration, to build up fat reserves.
Behaviour
Subalpine Warblers are active and agile, constantly flitting through dense vegetation in search of insects. They often hover briefly while foraging, a behaviour that distinguishes them from other warblers.
During the breeding season, males become territorial and perform display flights to attract mates.
Vocalisation
The Subalpine Warbler's song is a rapid, rattling trill, often described as 'trrrrrrt-trrrrrrt'. Their call is a soft 'tac' or 'tchac'.
Males sing persistently during the breeding season, often from exposed perches to defend territory and attract mates.
Nesting & Breeding
Breeding occurs from April to July, with males establishing territories through song and display flights. Pairs form monogamous bonds for the breeding season.
The female constructs a cup-shaped nest low in dense shrubs, using grasses, spider webs, and plant down. She typically lays 3-5 eggs, which are pale with brown speckles.
Incubation lasts about 12 days, primarily by the female. Both parents feed the chicks, which fledge after 11-12 days but remain dependent on adults for another two weeks.
Conservation and Status
Global Conservation Status
While currently listed as Least Concern, the Subalpine Warbler faces threats from habitat loss due to agricultural intensification and climate change.
Conservation efforts focus on preserving Mediterranean scrubland habitats and monitoring population trends across its range.
Population Data
Global Population Estimate
Not been quantified since the species was split
Birdwatching Tips
- Look for quick movements in low shrubs and bushes
- Listen for their distinctive rattling call
- Observe during spring migration in coastal areas
- Pay attention to the male's bright red eye ring for identification
Additional Information
Quick Facts
Predators
Did You Know?
- Subalpine Warblers can raise two broods in a single breeding season.
- They are one of the smallest warblers in Europe.
- Some individuals have been recorded living up to 7 years in the wild.
References
- 1
website: BirdLife International. 2019. Sylvia cantillans (amended version of 2018 assessment). The IUCN Red List of Threatened Species 2019: e.T103874024A155622649.
View source - 2
report, 2015: EBCC