Australian creepers

(Climacteridae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Climacteridae

Thumbnail description
Small to medium-sized, brown to blackish streaked birds with long toes and claws and curved bills that climb up tree trunks and branches

Size
5.7–6.9 in (14.5–17.5 cm); 0.75–1.15 oz (21–32 g)

Number of genera, species
2 genera; 7 species

Habitat
Forests, including rainforests, woodlands, and tall shrublands

Conservation status
Near Threatened: 1 subspecies of one species, and two subspecies of another species; remaining subspecies of both are of Least Concern

Distribution
Australia (except treeless regions), mountains of New Guinea, absent from
Tasmania

Evolution and systematics

Australian treecreepers resemble, in appearance and habits, the Northern Hemisphere creepers (Certhiidae) and a few other ecologically similar species elsewhere. However, this resemblance is the result of convergence due to occupying a similar niche. Details of their anatomy and behavior, and especially molecular studies, indicate that they are related to the large group of other Australian passerines. They do not seem to be closely related to any other family, but their nearest relatives are probably the lyrebirds and scrub-birds.

One genus, identified by Sibley and Monroe, consists of a superspecies including the polytypic white-throated tree-creeper (Cormobates leucophaea) and Papuan treecreeper (C. placens), the only species that occurs outside Australia. The other genus, Climacteris, is remarkably homogeneous.

Physical characteristics

Australian treecreepers are sparrow-sized or slightly larger, fairly robust, with a short neck and longish, decurved bills. Although their legs are short, all toes are long with very long and curved claws, which are presumably adaptations to tree climbing.

Their coloration ranges from rufous through brown to almost black. All species are streaked, sometimes boldly underneath, with white, black, and brown. Several have pale or white throats, and all have a pale stripe through the wing, which is prominent in flight. Sexual dimorphism is subdued, with females typically having orange patches on neck, throat, or breast.

Distribution

Treecreepers are found across Australia, but are absent from sandy and stony deserts and grasslands. These treeless areas often separate subspecies or populations of one species. For instance, the Great Sandy Desert in northwestern Australia lies between two subspecies of the black-tailed treecreeper (Climacteris melanura). The Nullarbor Plain lies between the southwestern and Eyre Peninsula populations of the rufous treecreeper (Climacteris rufa), though they maintain contact along a thin strip of wooded country on the edge of the Great Victoria Desert. Tasmania has no treecreepers despite having extensive rainforests, eucalypt forests, and woodlands, possibly because treecreepers are poor fliers and Tasmania had less forest when it became isolated from mainland Australia.

Despite its extensive forests, New Guinea only has tree-creepers in some of its mountains. The Papuan treecreeper has an inexplicable gap in distribution of about 250 mi (400 km) in central New Guinea.

Habitat

Only one species of treecreeper occurs in rainforest in Australia, with most of the other species in eucalypt forest and woodland. Brown (Climacteris picumnus) and rufous treecreepers are also found in mallee, which are low woodland with multi-stemmed eucalypts. However, they generally avoid areas with dense understory. Black-tailed and white-browed treecreepers (Climacteris affinis) are found in acacia woodland in semi-arid regions, with the latter also having a strong affinity with sheoke trees (Casuarina).

Behavior

Treecreepers are solitary or occur as pairs and family groups. Territorial defense may be strong at pair or group boundaries, involving much calling and chasing. They are strongly sedentary with no indication of migration, though young birds may disperse several miles (kilometers).

Most species have whistling or clicking calls. Displays include tail clicking and flicking.

Feeding ecology and diet

Most treecreepers forage by climbing up or along trunks and branches, typically of rough barked trees. Their strong claws allow them to cling upside-down, however, they rarely move down a trunk or branch. They capture insects by gleaning from the surface or probing into fissures in the bark or in peeling bark. Some species display a significant amount of ground foraging. Ants feature prominently in the diet, but

they take other insects, especially beetles, larvae, spiders, and nectar and seeds on rare occasions.

Reproductive biology

Although some species breed as pairs, most are cooperative breeders. Helpers consist of young males, rarely females, from earlier years. There is often a close relationship among neighboring groups, with males often only dispersing one or two territories from their homes, and helping may occur among groups. The breeding season ranges from August to January with repeated attempts, and sometimes two broods reared in a year. All species nest in tree hollows, at which females perform an unusual behavior of sweeping snakeskin, insect wings, or even plastic around the entrance. Clutches are usually two or three white to pinkish eggs with brown markings. Incubation takes from 14–24 days, and fledging from 25–27 days.

Conservation status

Clearance and degradation of woodland has led to the decline of several species, at least locally, with three subspecies being regarded as Near Threatened.

Significance to humans

None known.

Species accounts

List of Species

White-throated treecreeper

Cormobates leucophaeus

taxonomy

Certhia leucophaea Latham, 1802, Port Jackson, New South Wales, Australia.

other common names

English: Papuan treecreeper, little treecreeper; French: Échelet Leucophée; German: Weisskehl-Baumrutscher; Spanish: Sube Palo de Garganta Blanca.

physical characteristics

6 in (15 cm); 0.8 oz (22 g). Brownish gray upperparts with white throat and rufous patch at lower cheek; breast is buff streaked with white.

distribution

Eastern Australia from north Queensland to Adelaide region. Distinct subspecies in northeast Queensland, Clarke Range of central coastal Queensland, and Mount Lofty Ranges of South Australia.

habitat

Tropical, subtropical, and temperate rainforests, eucalypt forests, and woodlands.

behavior

Solitary or in pairs in strongly defended territories. Strident whistling and piping, and more subdued chattering calls, display by rapidly flicking tail open and closed with audible clicking sound.

feeding ecology and diet

Climbs up trunks and along branches of rough-barked eucalyptus and other trees, gleaning from the surface and probing into bark for ants and other arthropods.

reproductive biology

Breeds August–January, but mostly September/October, in hollows in the trunks or branches of living or dead trees, often eucalypts. Two or three eggs, incubated by female for 22–24 days. Nestlings fed by both parents, but only females brood chicks; fledging at 26 days.

conservation status

Secure, common and copes well with habitat fragmentation.

significance to humans

None known.

Red-browed treecreeper

Climacteris erythrops

taxonomy

Climacteris erythrops Gould, 1841, Liverpool Plains, New South Wales, Australia.

other common names

English: Red-eyebrowed treecreeper; French: Échelet à sourcils roux; German: Rostbrauen-Baumrutscher; Spanish: Sube Palo de Cejas Rojas.

physical characteristics

6.3 in (16 cm); 0.8 oz (23 g). Underparts brown streaked with white; gray head with rufous around eye, white throat, brown mantle, and grayish tail.

distribution

Southeastern Australia from Brisbane to Melbourne.

habitat

Eucalypt forests of the Great Dividing Range, less commonly in woodlands to the west of the range. Occasionally, temperate and subtropical rainforest. Especially associated with eucalypts that have peeling bark or that shed bark on their lower branches and trunks.

behavior

Lives in family groups in a large home range, but highly sedentary. Aggression and conflict between neighbors much less frequent than in the white-throated treecreeper. Rather soft, chattering calls.

feeding ecology and diet

Typically probe into bark of rough-barked trees, and especially into accumulations of peeling bark on gums and boxes (subgenus Symphyomyrtus) for insects such as spiders and especially ants.

reproductive biology

Breeds September–January in cooperative groups of three to four birds. Nests are placed in tree hollows, typically in a spout of a living tree. Clutch size is strictly two eggs, incubated by the breeding female for about 18 days. Young are fed by parents and helpers, and fledge at 25 days, with a high success rate (74% in New South Wales).

conservation status

Secure, but cope poorly with habitat fragmentation, and have contracted from the west of their range where woodland has been extensively cleared.

significance to humans

None known.

Rufous treecreeper

Climacteris rufa

taxonomy

Climacteris rufa Gould, 1841, Swan River, Western Australia.

other common names

English: Allied rufous treecreeper, wheelbarrow; French: Échelet roux; German: Rostbauch-Baumrutscher; Spanish: Sube Palo Rufo.

physical characteristics

6.7 in (17 cm); 1.1–1.2 oz (30–33 g). Rufous brow and cheek with black eye strip; underparts rufous streaked with white; gray-brown upperparts with rufous-brown tail.

distribution

Southwestern Australia, Eyre Peninsula of South Australia, with loose links between these populations.

habitat

Eucalypt woodland and forest; mallee.

behavior

Lives in family groups, consisting of a breeding pair and offspring from previous breeding seasons. Sedentary. Peeping calls, churring calls at predators.

feeding ecology and diet

Forages on trunks and lower branches of eucalypts and casuarinas, and also commonly on the ground, especially among fallen timber. Eats insects, especially ants, as well as centipedes and snails, small reptiles, and seeds.

reproductive biology

Breeds August–January in hollows in branches, stumps, and fallen logs. Female incubates one to three eggs for 17 days. Young are fed by parents and helpers, and fledge at 26 days, with high success (78% in one Western Australia study).

conservation status

Not threatened. Secure, but populations have declined or gone locally extinct in parts of the heavily cleared Wheatbelt of western Australia.

significance to humans

None known.

Resources

Books

Garnett, S.T., and G.M. Crowley. The Action Plan for Australian Birds 2000. Canberra: Environment Australia, 2000.

Higgins, P.J., J.M. Peter, and W.K. Steele, eds. Handbook of Australian, New Zealand and Antarctic Birds. Vol. 5, Tyrant-flycatchers to Chats. Melbourne: Oxford University Press, 2001.

Sibley, C.G. and J.E. Ahlquist. Phylogeny and Classification of Birds: A Study of Molecular Evolution. New Haven: Yale University Press, 1990.

Periodicals

Luck, G., A. Charmantier, and P. Ezanno. "Seasonal and Landscape Differences in the Foraging Behaviour of the Rufous Treecreeper Climacteris rufa." Pacific Conservation Biology 7 (2001): 9–20.

Noske, R. "Co-Existence of Three Species of Treecreepers in North-Eastern New South Wales." Emu 79 (1979): 120–128.

Noske, R.A. "Intersexual Niche Segregation among Three Bark-Foraging Birds of Eucalypt Forests." Australian Journal of Ecology 11 (1986): 255–267.

Noske, R.A. "A Demographic Comparison of Cooperatively Breeding and Non-Cooperative Treecreepers." Emu 93 (1993): 73–86.

Walters, J.R., H.A. Ford, and C.B. Cooper. "The Ecological Basis of Sensitivity of Brown Treecreepers to Habitat Fragmentation: A Preliminary Assessment." Biological Conservation 90 (1999): 13–20.

Hugh Alastair Ford, PhD