The motorbike frog (''Ranoidea moorei'') is a ground-dwelling

tree frog A tree frog (or treefrog) is any species of frog that spends a major portion of its lifespan in trees, known as an arboreal state. Several lineages of frogs among the Neobatrachia have given rise to treefrogs, although they are not closely relat ...

of the subfamily

Pelodryadinae Pelodryadinae, also known as Australian treefrogs (although not all members are arboreal), is a subfamily of frogs found in the region of Australia and New Guinea, and have also been introduced to New Caledonia, Guam, New Zealand, and Vanuatu. ...

found in

Southwest Australia Southwest Australia is a biogeographic region in Western Australia. It includes the Mediterranean-climate area of southwestern Australia, which is home to a diverse and distinctive flora and fauna. The region is also known as the Southwest Aus ...

. Its common name is derived from the male frog's

mating call A mating call is the auditory signal used by animals to attract mates. It can occur in males or females, but literature is abundantly favored toward researching mating calls in females. In addition, mating calls are often the subject of mate choic ...

, which sounds similar to a motorbike changing up through gears; it is also known as Moore's frog, the western bell frog, western green and golden bell frog, and western green tree frog.

Taxonomy

''R. moorei'' is a member of the ''

Ranoidea aurea The green and golden bell frog (''Ranoidea aurea''), also named the green bell frog, green and golden swamp frog and green frog, is a species of ground-dwelling tree frog native to eastern Australia. Despite its classification and climbing abi ...

'' complex (''

'', '' R. raniformis'' and ''

"Litoria" castanea "''Litoria''" ''castanea'', also known as the yellow-spotted tree frog, New England swamp frog, tablelands bell frog, or yellow-spotted bell frog, is a species of frog in the subfamily Pelodryadinae. It is a critically endangered species of fr ...

'').

Description

''R. moorei'' is able to camouflage itself well, and ranges in colour from dark brown, through green, to gold. The underside is noticeably lighter, and usually ranges from very pale green to light brown. The light green of the groin and thigh distinguishes this species from its cogenor, '' Ranoidea cyclorhynchus'', which is darker and spotted with yellow there. Typical of tree frogs, its toe pads enable it to climb smooth vertical surfaces. Its hind legs are powerful, and the toes are webbed. In mating season, the males develop black

nuptial pad A nuptial pad (also known as thumb pad, or nuptial excrescence) is a secondary sex characteristic present on some mature male frogs and salamanders. Triggered by androgen hormones, this breeding gland (a type of mucous gland) appears as a spiked ...

s that enable them to cling to the females' backs during

amplexus Amplexus (Latin "embrace") is a type of mating behavior exhibited by some externally fertilizing species (chiefly amphibians and horseshoe crabs) in which a male grasps a female with his front legs as part of the mating process, and at the same ...

. ''R. moorei'' can be up to 7.5 cm in length. The

tadpole A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found i ...

's body is a uniform dark brown above with a silvery sheen below; initially minute in size, they grow to a very large 80 mm in length. The tadpoles usually hide amongst vegetation, but are easily encouraged out of hiding when food is presented. For most of their time as tadpoles, they crowd together in schools.

Distribution and habitat

South-west corner of Western Australia, from as far north as the

Geraldton Sandplains Geraldton (Wajarri: ''Jambinu'', Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West region of the Australian state of Western Australia, north of the state capital, Perth. At June 2018, Geraldton had an urban population of 37,648. ...

, to the

Esperance Plains Esperance Plains, also known as Eyre Botanical District, is a biogeographic region in southern Western Australia on the south coast between the Avon Wheatbelt and Hampton bioregions, and bordered to the north by the Mallee region. It is a pl ...

on the south coast of WA. A population exists on

Rottnest Island Rottnest Island ( nys, Wadjemup), often colloquially referred to as "Rotto", is a island off the coast of Western Australia, located west of Fremantle. A sandy, low-lying island formed on a base of aeolianite limestone, Rottnest is an A-class ...

, and the species is one of the most well known frogs found in urban

Perth Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth is ...

areas. The estimated altitudinal range of the species is from 0–600 m asl. A wide and populous distribution through lakes and swamps has readily incorporated garden ponds and farm dams, where they are often found sunbathing on the upper leaves of plants.

Ecology and behaviour

Breeding season is from early spring through to late summer. The male's mating call sounds like a motorbike changing gears. The males usually find a suitable clump of reeds or other water plants from which to call. When a female joins the male in the water, the male grips onto the female's back, using his nuptial pads, that appear during breeding season. Large clumps of eggs, encased in a transparent jelly, are attached to floating vegetation and debris. Despite being a tree frog, ''R. moorei'' seldom climbs higher than 1–2 m, on plants, shrubs, brick walls, or windows. Their diets consist mainly of arthropods, but also include smaller frogs, including juveniles of the same species. The tadpole's main diet is algae, but they also eat animal matter when available. Tadpoles, like adult frogs, sunbathe for one or two hours each day for healthy growth. They can live without water for extended periods of time.

Threats

Unlike the eastern members of the species complex, the motorbike frog has not suffered from dramatic declines, despite

chytrid fungus Chytridiomycota are a division of zoosporic organisms in the kingdom Fungi, informally known as chytrids. The name is derived from the Ancient Greek ('), meaning "little pot", describing the structure containing unreleased zoöspores. Chytrids ...

being present in areas which they inhabit.

References

External links

* * {{Taxonbar, from=Q1949965 Litoria Amphibians of Western Australia Articles containing video clips Amphibians described in 1957 Frogs of Australia Taxobox binomials not recognized by IUCN