Rock-jumper
Encyclopedia
The Rock-jumpers are medium-sized insectivorous or omnivorous bird
s in the genus Chaetops, which constitutes the entire family Chaetopidae. The two species, the Rufous Rock-jumper
, Chaetops frenatus, and the Drakensberg Rockjumper, Chaetops aurantius, are endemic residents of southern Africa
. The Rufous Rock-jumper (or Cape Rock-jumper) is a resident of the West Cape and SW East Cape, and the Orange-breasted (or Drakensberg) Rock-jumper is distributed in the Lesotho
highlands and areas surrounding this in South Africa
. The two rock-jumpers have been treated as separate species but differ in size and plumage
. The ranges do not overlap, but come close to doing so.
Originally, these birds were placed in the thrushes, and they have also been placed with the Old World warblers
and the babblers, but recent DNA studies indicate these birds are actually primitive passerine
s most closely related to the rockfowl (Picatharthidae), a family in which they are sometimes placed.
These are small birds with mostly brown and red plumage
. Both species have long, white tipped black tails, black throats, broad white submoustachial lines, rufous or orange bellies and rumps and grey and black patterned backs and wings. The iris is red and the bills and legs are black. Their wings are very small and they do not fly very often. They spend most of their lives running and jumping among rocks and grasses while hunting insects. A range of insects are taken, including caterpillars, moths, grasshoppers, beetles and flies. In addition to insects other prey include lizards and geckos, amphibians, scorpions, annelid worms and spiders.
They are monogamous
and pairs establish territories
which are defended year round. In the Rufous Rock-jumper the territories vary in size from 4–11 ha (9.9–27.2 acre). Both species employ helpers, usually the young of previous broods, to aid the breeding pair in raising the young. Nests are built out of grass on the ground (in contrast to rockfowl, which build mud nests in colonies). The clutch size is two eggs for the Rufous and two to three eggs for the Orange-breasted. Both sexes incubate
the clutch for 19–21 days. The chicks are fed by the parents and helpers for thirty days, but they leave the nest sooner than that.
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s in the genus Chaetops, which constitutes the entire family Chaetopidae. The two species, the Rufous Rock-jumper
Rufous Rock-jumper
The Rufous Rock-jumper or Cape Rock-jumper, Chaetops frenatus is a medium-sized insectivorous passerine bird endemic to the mountain fynbos of southernmost South Africa....
, Chaetops frenatus, and the Drakensberg Rockjumper, Chaetops aurantius, are endemic residents of southern Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. The Rufous Rock-jumper (or Cape Rock-jumper) is a resident of the West Cape and SW East Cape, and the Orange-breasted (or Drakensberg) Rock-jumper is distributed in the Lesotho
Lesotho
Lesotho , officially the Kingdom of Lesotho, is a landlocked country and enclave, surrounded by the Republic of South Africa. It is just over in size with a population of approximately 2,067,000. Its capital and largest city is Maseru. Lesotho is a member of the Commonwealth of Nations. The name...
highlands and areas surrounding this in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
. The two rock-jumpers have been treated as separate species but differ in size and plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
. The ranges do not overlap, but come close to doing so.
Originally, these birds were placed in the thrushes, and they have also been placed with the Old World warblers
Sylviidae
Sylviidae is a family of passerine birds that was part of an assemblage known as the Old World warblers. The family was formerly a wastebin taxon with over 400 species of bird in over 70 genera. The family was poorly defined with many characteristics shared with other families...
and the babblers, but recent DNA studies indicate these birds are actually primitive passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
s most closely related to the rockfowl (Picatharthidae), a family in which they are sometimes placed.
These are small birds with mostly brown and red plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
. Both species have long, white tipped black tails, black throats, broad white submoustachial lines, rufous or orange bellies and rumps and grey and black patterned backs and wings. The iris is red and the bills and legs are black. Their wings are very small and they do not fly very often. They spend most of their lives running and jumping among rocks and grasses while hunting insects. A range of insects are taken, including caterpillars, moths, grasshoppers, beetles and flies. In addition to insects other prey include lizards and geckos, amphibians, scorpions, annelid worms and spiders.
They are monogamous
Monogamy
Monogamy /Gr. μονός+γάμος - one+marriage/ a form of marriage in which an individual has only one spouse at any one time. In current usage monogamy often refers to having one sexual partner irrespective of marriage or reproduction...
and pairs establish territories
Territory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
which are defended year round. In the Rufous Rock-jumper the territories vary in size from 4–11 ha (9.9–27.2 acre). Both species employ helpers, usually the young of previous broods, to aid the breeding pair in raising the young. Nests are built out of grass on the ground (in contrast to rockfowl, which build mud nests in colonies). The clutch size is two eggs for the Rufous and two to three eggs for the Orange-breasted. Both sexes incubate
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
the clutch for 19–21 days. The chicks are fed by the parents and helpers for thirty days, but they leave the nest sooner than that.