Recurvirostra novaehollandiae Vieillot, 1816

Bill Morphology and Function

The red-necked avocet (Recurvirostra novaehollandiae Vieillot, 1816), like all avocet species, has a distinctive upcurved bill, which it uses to skim the surface of water to catch small invertebrates.

Adult Head and Neck Plumage

Adult red-necked avocets have a rich chestnut brown head and neck — the feature that gives the species its common name — along with a narrow white eye ring and a red-brown iris.

Body Plumage

Their secondary coverts and primary feathers are black, and the rest of their plumage is white.

Bill and Leg Color

The bill is black, and the legs are pale grey-blue.

Sexual and Seasonal Plumage Variation

Males and females are similar in both coloration and size, and there is no seasonal variation in appearance.

Juvenile Appearance

Juveniles resemble adults and are difficult to distinguish once post-juvenile moult begins; their heads are sometimes paler and browner than adults' heads.

Adult Size Measurements

On average, adult red-necked avocets measure 43–45 cm (17–17.5 in) from head to tail, have a total wingspan of approximately 75 cm (29.5 in), with a wing length of 22.4–23 cm, tail length of 7.9–8.8 cm, bill length of 8.2–9.5 cm, and a body weight of around 310 g.

Vocalization Description

The species' call has been described as yapping, and flocks in flight produce a sound similar to barking dogs.

Nomadic Movement Drivers

Like many Australian waterbirds, the red-necked avocet is highly nomadic, largely in response to highly variable rainfall across the continent, and moves around Australia to find suitable habitat.

Australian Distribution Range

It has a very wide range across Australia, but is comparatively rare on the northern and north-eastern coasts.

Preferred Habitat Types

It prefers salt or brackish water, and is generally found in shallow freshwater or saltwater wetlands, or on estuarine mudflats.

Occurrence Outside Mainland Australia

It is rare in Tasmania, and is an occasional vagrant to New Zealand.

Breeding Season Social Structure

During the breeding season, red-necked avocets are mainly found in loose colonies, and disperse into small flocks for the rest of the year.

Interspecific Social Behavior

They are social in all activities and during all seasons, and readily associate with stilts.

Courtship and Mating Behavior

Pre-mating courtship includes bill crossing and bowing dances; the female indicates readiness to mate by crouching low with spread wings, and this interaction usually takes place in shallow water.

Nesting Territory Defense

Each breeding pair defends its nesting territory through a range of displays and postures, and will swoop repeatedly at intruders.

Vocalization Similarity to Other Avocets

The red-necked avocet's vocalizations are similar to those of other avocets.

Specific Call Types and Functions

Common calls include a clear, fluty 'tuut' or 'kluut' that generally acts as a contact call, while shorter, sharper yelping notes are used as warning calls.

Sedentary and Movement Patterns

When conditions are suitable, the species can be fairly sedentary, but will quickly move to coastal areas during dry weather.

Breeding Colony Timing

Red-necked avocets nest in loose, rarely large, colonies, mainly between August and November.

Breeding Timing Drivers

Breeding timing is highly variable, and depends on rainfall and water availability.

Breeding Location Records

Breeding most often occurs in the south-western interior on swamps and mudflats after rain, though small breeding colonies have been recorded on Port Phillip Bay near Melbourne, Victoria.

Nest Construction

The nest is a shallow scrape lined with samphire or similar aquatic vegetation.

Egg Characteristics

Clutch size is 3–4 eggs, most often 4; the eggs are pyriform, pale brown with some speckled sepia markings, and measure 36 by 50 mm.

Egg Arrangement

The eggs are arranged in a circle, with their narrow acute ends pointing toward the center.