Birda Logo
Species Guide

Slender-billed Thornbill

Acanthiza iredalei

The Slender-billed Thornbill, Acanthiza iredalei, is a diminutive avian species endemic to Australia. This bird is characterized by its modest size, measuring between 9 to 10 centimeters in length. It boasts an olive-grey to olive-brown back, with the base of its tail displaying an olive-yellow hue. The underbelly is a smooth cream, and it is distinguished by its dark bill and pale eyes.

Identification Tips

When attempting to identify the Slender-billed Thornbill, look for its small stature and the distinctive coloration of its plumage. The olive-yellow base of the tail is a key feature, as is the contrast between the bird's cream underbelly and its darker upper parts. The dark bill and pale eyes are also notable identifiers.


The Slender-billed Thornbill is typically found in shrublands and salt marshes, particularly those surrounding salt lakes or situated on low heath on sand plains.


This species includes three subspecies with distinct distributions. The A. i. iredalei subspecies inhabits six isolated populations in Western Australia and a significant population in the Carnarvon bioregion. The A. i. hedleyi subspecies is located in southeastern South Australia and western Victoria, while the A. i. rosinae subspecies is most commonly found in the Gulf St Vincent region of South Australia.


The Slender-billed Thornbill is a sociable bird, rarely observed alone. It is usually seen in flocks of around eight or in pairs. It prefers to feed at higher elevations in shrubs and trees, seldom descending to the ground.


Nests of the Slender-billed Thornbill are small and constructed within low shrubs. They are made from grass, bark, cobwebs, and other debris found in their shrubland habitat. Females lay up to three eggs during the breeding season, which spans from July to November.

Diet and Feeding

The diet of the Slender-billed Thornbill consists mostly of insects and spiders, which it captures in the shrubs of its habitat.

Conservation status

The conservation status of the Slender-billed Thornbill varies by subspecies. The A. i. rosinae is considered vulnerable, while the A. i. hedleyi is near threatened. The A. i. iredalei subspecies is also deemed vulnerable. Notably, the A. i. iredalei subspecies is extinct in northern Australia, marking it as the only indigenous species to have become extinct in that region since European settlement. In Victoria, the A. i. hedleyi is listed as threatened under the Victorian Flora and Fauna Guarantee Act 1988, though an Action Statement for its recovery has not been prepared.

App logo
Birda is a birdwatching app and community aimed at curious people who want to deepen their connection with nature.

More Australasian Warblers

A photo of a Inland Thornbill (Acanthiza apicalis)

Inland Thornbill

Acanthiza apicalis
Birda Logo

Your birdwatching journey like never before

Connect with nature in minutes
Take a walk, look out of the window and log the birds that you see. Feel good about those little connections to nature.
Discover the joy of birding
Find new birding spots, see more birds, share and celebrate with a like-minded community of nature lovers.
Play your part in saving nature
Logging your birding sightings and sessions turns into positive action for our planet. Every sighting counts.

Birda Blog

What Our Birders Say
Awesome App
I really enjoy using this app! It is such a friendly community of bird-lovers who are happy to help if I need ID advice. It’s been great motivation to get outdoors and go birding more! 10/10 😍😍
Gets me outdoors more
I'm still loving this app. I use it most days & gets me outdoors more. Enjoying watching others progress and photo's, it's improved my wellbeing.... I love this app! I can keep a record of sightings and see what others have seen too.
We've been waiting for an App like this
Excellent! We've been waiting for an app like this! Thank you! It would be nice if you could assign additional birds to sessions later!
Amylia S
Best app for any birding person!
I love this app!! I am so addicted to it when I saw it had 3 star review I was so sad! The app is awesome!! The best app for any birding person! ❤️
A mordern game changer
Birda is an awesome app, its updated the world of birding to the modern day with a fun and easy to use app. It’s engaging and allows positive interaction with fellow bird lovers!
Hip An
Really enjoying Birda where I live i have a lot of Red kites really hard to photograph but I can video are you planning some place on the app where us Birda can post vids🦉🦅
Great app for beginner twitchers
I’ve had a passion of photographing birds for a long time now but have only just gotten into proper birdwatching, and this app is brilliant for those just getting started. There is a great sense of community among users and the app is very easy to use and professional. Awesome app altogether
Great app for learning Birds
I’ve been using the app for a couple of months and love it....Someone said it’s like a real life Pokémon Go for birds. They’re not far off! It’s something that the family can do that gets you out and about. Well worth downloading no matter your age.
Alex J
Friendly and helps to identify birds
Great birding app, good for logging your sightings, also has nice species guide. I'm enjoying the social aspect more than I expected, everyone seems friendly and helps to identify unknown birds. Good mix of newbies and experienced users.
A Friendly Place
I love using the bird app, I have a pretty good knowledge of birds. But I do have some gaps in it, so it’s nice to have a safe space to check on a sighting to confirm the species. It’s really enjoyable and I love the badges you can collect. It’s like a real life Pokémon go.
As featured in
AboutPressAmbassadorsAffiliatesInfluencersCareersPrivacyTerms & Conditions
An app for birdwatchers
Giving back
Connect with us
Copyright © 2024 Chirp Birding. All rights reserved.