Photo: Rick elis.simpson / CC BY-SA 3.0 (Wikimedia Commons)
Marsh Antwren
Formicivora acutirostris
Marsh Antwren (Formicivora acutirostris) — Songbirds & Perching Birds of South America.
Found across 2 guides in our atlas — open any for the full checklist, photos and what's around right now.
The Marsh Antwren (Formicivora acutirostris) is a member of the Thamnophilidae family found in South America. Adults weigh 10 g. The IUCN Red List lists it as Near Threatened.
Conservation status
IUCN Red List (opens in a new tab)Close to qualifying for a threatened category in the near future.
Where it fits
- Class Aves
- Order Passeriformes
- Family Thamnophilidae Antbirds
- Genus Formicivora
- Species acutirostris
Quick facts
- Weight
- 10 g
- Diet
- Invertebrate-eaters
- Family
- Thamnophilidae
- Order
- Passeriformes
- Habitat
- Wetland, lake & coast
How to identify
Similar birds
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Biology & behaviour
Diet
The Marsh Antwren is a invertivore — it feeds mainly on invertebrates such as insects and other small prey.
Behaviour
A bird of wetlands, it spends much of its time perched in trees and shrubs.
Migration
The Marsh Antwren is largely sedentary, staying within its range year-round rather than making regular long-distance migrations.
The Marsh Antwren (Formicivora acutirostris) belongs to the Thamnophilidae family of the order Passeriformes. It occurs naturally across South America. Its distribution covers SA se Brazil.
It is a very small bird. Adults weighs around 10 g, with a wing length of about 5.1 cm and a tail of around 6.1 cm.
The IUCN Red List lists it as Near Threatened. That means it is close to qualifying as threatened and is worth keeping a careful eye on.
The species has a mapped global range of roughly 881 km² — a relatively restricted global range.
Songs & calls
Frequently asked questions
How big is the Marsh Antwren?
The Marsh Antwren is a very small bird that weighs around 10 g.
Where does the Marsh Antwren live?
The Marsh Antwren is found across South America with a range covering SA se Brazil, where it is associated with wetlands, lakes and other open water.
What family does the Marsh Antwren belong to?
The Marsh Antwren (Formicivora acutirostris) belongs to the Thamnophilidae family, in the order Passeriformes.
What does the Marsh Antwren eat?
The Marsh Antwren is a invertivore — it feeds mainly on invertebrates such as insects and other small prey.
Does the Marsh Antwren migrate?
The Marsh Antwren is largely sedentary, staying within its range year-round rather than making regular long-distance migrations.
Is the Marsh Antwren endangered?
The IUCN Red List lists it as Near Threatened That means it is close to qualifying as threatened and is worth keeping a careful eye on.
What sound does the Marsh Antwren make?
1 real field recording of the Marsh Antwren — including its call — can be played in the Songs & calls section on this page, credited to the recordist who captured it.
How large is the Marsh Antwren's range?
The Marsh Antwren has a mapped global range of about 881 km².
Conservation
Every bird benefits from bird-safe windows, native plants, and keeping cats indoors. Small changes at home add up to real protection.
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Guides for this bird
Best Bird Feeders for Garden Songbirds
How to choose a bird feeder for garden songbirds — the feeder styles compared, the seed they prefer, where to hang it, and how to keep birds safe. A decision framework grounded in real data, with no mystery picks.
Meet the Thamnophilidae
A field guide to the Thamnophilidae family — 240 species in the Birbs encyclopedia, with the best-known members to start with.