Cape Barren Goose

BirdAustralia

Feb 11

Cereopsis novaehollandiae

The Cape Barren goose is perhaps the least aquatic of all geese — it seldom enters water, except to save its chicks. An aggressively protective parent, it chases away larger animals, including humans, by battering them with the hard "wrist" bones on its wings and pecking with its knobby beak.

Imagine a goose. Now make it bigger and plumper, shorten its beak into a knobby yellow thing tipped with black, paint its legs pink, dip its feet in ink, and give its feathers a dusting of ash — and, if you'd like, add some black dots to its wings for decoration. You've got yourself a Cape Barren goose, or at least something approximating one. The real thing is found in southern Australia and is among the rarest geese in the world.¹

A Time of Peace

Cape Barren Island lies in the Bass Strait between southeast Australia and northeast Tasmania.² The geese aren't restricted to this one island — their range today extends across much of Victoria's and Western Australia's southern coasts, as well as several southern islands, including Tasmania — but Cape Barren was the first place they were spotted, and so the name has stuck.

The austral summer, between December and February, is "peacetime" for the Cape Barren geese (as peaceful as geese get, anyway). They are outside of their breeding season, living along the mainland coasts and on large islands like Flinders, and they spend most of their days grazing in gregarious flocks up to 70 strong. On their tall, red-black legs, the geese stride across pastures and fields of tussock grass, nipping at vegetation — no algae or pondweed for these geese, as they are poor swimmers that rarely enter the water. They are grazers, subsisting on purely terrestrial and vegetarian diets of grasses, herbs, succulents, barley, legumes, and clover.

The approach of austral winter in May stirs something in the geese; a drive to take to the wing, to fly — slowly and somewhat clumsily, given their bulk. The males in midflight trumpet excitedly (“ark ark-ark, ark-ark”). The females respond with deep, pig-like grunts — like a bully bestowing a nickname for some mildly embarrassing quirk, we have colloquially christened this bird as the "pig goose" for its in-flight grunts. And so, the time has come when pigs fly, and people must reckon with their proclamations of disbelief. The winged swine soar over choppy seas in search of ancestral isles where they will soon sire their descendants.

A Time of Violence

The Cape Barren goose's eponymous island is one of coastal dunes, wetlands, and low hills covered in grasses and scrubby bushes. Cape Barren — as well as smaller, uninhabited, predator-free islands of the Bass Strait — are ideal breeding and nesting grounds. Some geese fly even further afield, out to open sea to find isolated nurseries, surviving by their ability to drink salt water. Upon arriving on its chosen island, a goose reunites with its life-long partner and establishes a territory. During their courtship displays, the two lovers are each other's whole worlds, paying no attention to the other geese around them, and once a couple has copulated, the male often stretches his neck and unfurls his wings in a so-called “triumph ceremony".³ The male builds a ground nest among tussocks of grass and lines it with soft down, into which the female lays 3 to 6 creamy-white eggs. The female incubates, but once the eggs hatch into goslings — all fuzzy in down feathers, with little black masks and dumpy, ink-blotched bodies — both parents care for and protect them with unrivalled intensity.

The geese's breeding season (May to September) awakens in them a seafaring urge and a romantic passion, yes, but above all, it brings forth a great violence — a defensive violence, but a great violence nonetheless.

The Cape Barren goose is big and bellicose; among the most belligerent of an already feisty group of birds. It stands around 75 centimetres (2.5 ft) tall and weighs upwards of 5 kilograms (11 lbs), but it won't hesitate to come at intruders larger than itself, with humans no exception from its hit list. Wander into this goose's territory, come too close to its nest, and it'll nip you with its hooked beak, scratch you with its sharp claws, and beat you with its wings — which bear the bird equivalent of brass knuckles in the form of hard carpal, or wrist, knobs (so technically, "bone wrists," rather than brass knuckles). It is an aggressively protective and dedicated parent. For this uniquely terrestrial goose, a chick in danger is just about the only thing that might make it wade into deep water.

Misidentification & Exploitation

A Cape Barren goose on the bottom left, a barnacle goose (*Branta leucopsis*) on the top, and a juvenile black swan (Cygnus atratus) on the right — not much resemblance.

The Cape Barren goose's relationship with humanity — at least Western, colonial humanity — has been bumpy from the start. When it was first spotted on the scrubby hills of Cape Barren in 1798, George Bass (whom the strait is named after) and Matthew Flinders (whom the strait's largest island is named after) referred to it as a "Brent [Brant] or Barnacle Goose." Others mistook this goose for a juvenile of the native Australian black swan, which is also grey, but otherwise shares little resemblance with the goose. The Cape Barren goose was officially described in 1801, and what followed was 150 years of its exploitation.

Going by early written accounts, this ample goose had been driven to near extinction by settlers come the turn of the twentieth century. By the 1950s, Cape Barren goose populations were so low that biologists feared the bird would go extinct. No piggy grunts trumpeted through the skies. The hills and coasts of Cape Barren were barren of geese. But the goose didn't go extinct. Through the actions of various wildlife agencies and conservationists — and the adaptability of the goose itself, which turned to feeding on agricultural land — this pugnacious bird has rebounded and, as of the last assessment, is considered a species of 'least concern', sitting at a population of 11,000 to 12,000 mature individuals.

A Hawaiian goose or nēnē (*Branta sandvicensis*).

¹ Perhaps not the rarest of all geese.

That would be the nēnē, or Hawaiian goose. When Captain James Cook made landfall in Hawaii in 1778, there were estimated to be some 25,000 nenes across the archipelago. In 1951, the entire wild nēnē population was comprised of some 30 individuals. The species was brought low by hunting, habitat destruction/degradation, and invasive mammals such as rats, cats, dogs, and ferocious small Indian mongooses. It has since recovered from its dismal low of the 50s and its population (as of 2022) sits at 3,862 individuals across Hawaii.

Cape Barren Island in the Bass Strait between southeast Australia and northeast Tasmania.

² Cape Barren Island is part of the Furneaux Group, in the southeastern part of the Bass Strait. In this group, it is second in size only to Flinders Island — Cape Barren having an area of 478-square-kilometre (185 sq mi). The island has a population of around 70 people, with most being descended from a community of mixed European and Aboriginal people, who now live mostly in the north-western corner of Cape Barren.

³ The "triumph ceremony" is common among many species of geese. Is this macho boasting or just innocent ecstasy? Well, the display likely serves a social function in forming or cementing the bond between a couple, with older pairs relying less on such ritualistic displays than younger ones.

**Where Does It Live?**

⛰️ Mainland and offshore islands in areas of areas of pasture, tussock grass or low heathy scrub.
📍 Southern Australia and Tasmania.

‘Least Concern’ as of 09 August, 2018.

IUCN

Size // Medium
Wingspan // 160 – 185 cm (5.2 - 6 ft)
Length // 75 cm - 100 cm (2.5 - 3.3 ft)
Weight // 3.1 - 6.8 kg (7 - 15 lbs)
Activity: Diurnal ☀️
Lifestyle: Social / Pair 👥
Lifespan: 15 - 18 years
Diet: Herbivore
Favorite Food: Grasses 🌾
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Cereopsis
Species: C. novaehollandiae

The Cape Barren goose is not exclusive to Cape Barren — an island that lies between Australia and Tasmania. It ranges throughout southern Australia and across Tasmania, but Cape Barren Island was the first place this goose was spotted, and the name stuck.

This goose is staunchly anti-aquatic. It eats no algae or pondweed, subsisting instead on a terrestrial grazer's diet of grasses, herbs, legumes and clovers.

During the austral summer, these geese live in gregarious flocks up to 70 strong and are fairly peaceful. The austral winter — the start of breeding season — brings violence.

To breed, flocks of Cape Barren geese disperse to smaller offshore islands. They fly slowly and laboriously, the males trumpeting excitedly (“ark ark-ark, ark-ark”) in midflight, while the females respond with deep, pig-like grunts — giving this species the nickname of "pig goose".

The Cape Barren goose is an exceedingly protective parent — a chick in danger is one of the few things that would bring it to enter water.

This goose strikes an imposing figure, standing around 75 centimetres (2.5 ft) tall and weighing upwards of 5 kilograms (11 lbs).

If anything or anyone wanders too close to its nest, this goose will nip with its hooked beak, scratch with its sharp claws, and beat the intruder with its wings — which are armed with hard carpal, or wrist, knobs.

The Cape Barren goose is (or was) among the rarest geese in the world. Officially described in 1801, the species was nearing extinction by the 1950s. Fortunately, its population recovered and, as of its last assessment, it numbers between 11,000 and 12,000 mature individuals.