The tomtit (''Petroica macrocephala'') is a small

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by th ...

bird in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Petroicidae, the Australasian robins. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to the islands of

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the ...

, ranging across the main islands as well as several of the outlying islands. In

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

, the North Island Tomtit is known as miromiro and the South Island Tomtit is known as ngirungiru. This bird has several other

and

English English usually refers to: * English language * English people English may also refer to: Peoples, culture, and language * ''English'', an adjective for something of, from, or related to England ** English national id ...

names as well. There are several subspecies showing considerable variation in

plumage Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...

and size. The species is not threatened and has adapted to the changes made to New Zealand's

biodiversity Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic ('' genetic variability''), species ('' species diversity''), and ecosystem ('' ecosystem diversity' ...

Etymology

The term ''tomtit'' was originally a shortened form of ''tom titmouse''. Either form has been used to describe a number of small birds, but in England ''tomtit'' was most commonly used as an alternate name of the

blue tit The Eurasian blue tit (''Cyanistes caeruleus'') is a small passerine bird in the tit family, Paridae. It is easily recognisable by its blue and yellow plumage and small size. Eurasian blue tits, usually resident and non-migratory birds, ...

. The word tit is today used for a number of small birds, especially of the family

Paridae The tits, chickadees, and titmice constitute the Paridae, a large family of small passerine birds which occur mainly in the Northern Hemisphere and Africa. Most were formerly classified in the genus ''Parus''. Members of this family are comm ...

. Originally, it was used for any small animal or object.

Taxonomy and evolution

The tomtit is one of four species of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

Petroica ''Petroica'' is a genus of Australasian robins, named for their red and pink markings. They are not closely related to the European robins nor the American robins. The genus was introduced by the English naturalist, William John Swainson, in 1 ...

'' found in New Zealand, the ancestors of which colonised from Australia. The species was once thought to have been descended from the

scarlet robin The scarlet robin (''Petroica boodang'') is a common red-breasted Australasian robin in the passerine bird genus ''Petroica''. The species is found on continental Australia and its offshore islands, including Tasmania. The species was original ...

, although more recent research has questioned this. It seems likely that there were two colonisation events, with the North Island robin and the South Island robin descended from one event, and the

black robin The black robin or Chatham Island robin ( Moriori: ''karure'', mi, kakaruia; ''Petroica traversi'') is an endangered bird from the Chatham Islands off the east coast of New Zealand. It is closely related to the South Island robin (''P. austral ...

and tomtit from another.Miller, Hilary C. & Lambert, David M. (2006): A molecular phylogeny of New Zealand’s Petroica (Aves: Petroicidae) species based on mitochondrial DNA sequences. ''Molecular Phylogenetics and Evolution'' 40(3): 844-855. There are five subspecies of the tomtit, with each subspecies being restricted to one of the following islands or island groups: North Island, South Island, the Snares Islands, the Chatham Islands, and the Auckland Islands. Four of these five subspecies have been elevated to full species in the past (the Chatham subspecies was retained with the South Island tomtit),R.N. Holdaway, T.H. Worthy and A.J.D. Tennyson,(2001) "A working list of breeding bird species of the New Zealand region at first human contact/" ''NZ J. Zool.'' 28: pp. 119–187 but genetic studies have shown that these subspecies diverged relatively recently. *North Island tomtit ''P. m. toitoi'' *South Island tomtit ''P. m. macrocephala'' * Chatham tomtit ''P. m. chathamensis'' *Auckland tomtit ''P. m. marrineri'' *Snares tomtit ''P. m. dannefaerdi''

Description

The tomtit is a small (13 cm, 11 g) bird with a large head and a short bill. The male

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-larges ...

subspecies has black head, back, wings (with a white wing-bar), and a white belly. The subspecies from

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasma ...

, the

Chatham Islands The Chatham Islands ( ) ( Moriori: ''Rēkohu'', 'Misty Sun'; mi, Wharekauri) are an archipelago in the Pacific Ocean about east of New Zealand's South Island. They are administered as part of New Zealand. The archipelago consists of about t ...

, and

Auckland Islands The Auckland Islands ( Māori: ''Motu Maha'' "Many islands" or ''Maungahuka'' "Snowy mountains") are an archipelago of New Zealand, lying south of the South Island. The main Auckland Island, occupying , is surrounded by smaller Adams Islan ...

are similar, but have a yellow band across the breast between the black head and white belly. The females are brown instead of black. The Snares Island subspecies is entirely black, and is known as the black tit.Heather, B & Robertson, H. (1996) ''The Field Guide to the Birds of New Zealand'' Auckland:Viking The island subspecies of tomtits show a striking variation in body size, being considerably larger than their mainland relatives, a tendency known as the Foster's rule or the island effect. Birds from the main islands weigh around 11g, compared with birds from Snares Island, which weigh in at 20 g.

Behaviour

Nests of South-Island Tomtit (Myiomoira macrocephala)

The tomtit is mostly an

insectivore A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...

, feeding on small invertebrates, such as

beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

s, caterpillars,

spider Spiders (order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species d ...

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of ...

wētā Wētā (also spelt weta) is the common name for a group of about 100 insect species in the families Anostostomatidae and Rhaphidophoridae endemic to New Zealand. They are giant flightless crickets, and some are among the heaviest insects in th ...

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. ...

s, and flies. Fruit is taken during the winter and autumn. Most subspecies feed in vegetation, waiting on a perch and watching for

prey Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

Insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs ...

s are also gleaned from branches and leaves. The Snares subspecies feeds on the ground as well, in a similar fashion to the

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''no ...

or South Island robins.

References

External links