The red-billed gull (''Chroicocephalus novaehollandiae scopulinus''), also known as tarāpunga and once also known as the mackerel gull, is a native 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 smaller islands. It is the sixth-largest island count ...

, being found throughout the country and on outlying islands including 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 te ...

and

subantarctic The sub-Antarctic zone is a region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region includes many islands ...

islands. It was formerly considered a separate species but is now usually treated as a subspecies of the

silver gull The silver gull (''Chroicocephalus novaehollandiae'') is the most common gull of Australia. It has been found throughout the continent, but particularly at or near coastal areas. It is smaller than the Pacific gull (''Larus pacificus''), which ...

(''Chroicocephalus novaehollandiae''). The

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 C ...

name of this species is tarāpunga or akiaki. Its vernacular name is sometimes also used for the

dolphin gull The dolphin gull (''Leucophaeus scoresbii''), sometimes erroneously called the red-billed gull (a somewhat similar but unrelated species from New Zealand), is a gull native to southern Chile and Argentina, and the Falkland Islands. It is a coasta ...

, a somewhat similar-looking but unrelated species that is found in coastal

southern Chile Southern Chile is an informal geographic term for any place south of the capital city, Santiago, or south of Biobío River, the mouth of which is Concepción, about {{convert, 200, mi, km, sigfig=1, order=flip south of Santiago. Generally cities ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

and the

Falkland Islands The Falkland Islands (; es, Islas Malvinas, link=no ) is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and about from Cape Dubouze ...

. As is the case with many gulls, the red-billed gull has traditionally been placed in 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 nom ...

Larus ''Larus'' is a large genus of gulls with worldwide distribution (by far the greatest species diversity is in the Northern Hemisphere). Many of its species are abundant and well-known birds in their ranges. Until about 2005–2007, most gulls ...

''. A national survey of breeding red-billed gulls carried out in 2014–2016 recorded 27,831 pairs nesting in New Zealand. The authors of the study based on the survey and published in 2018 said that the accuracy of previous estimates was questionable, but that the species nevertheless appeared to have declined nationally since the mid-1960s. The study also discussed the possible reasons for the decline and made a proposal for future monitoring.

Description

The red-billed gull is a fairly small

gull Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century ...

with an all-red bill, red eye ring, red legs and feet, pale grey wings with black wingtips. The rest of the body and tail are white. There is virtually no visual difference between the male and female birds. Juvenile gulls have a dark brown bill with only hints of red, making them difficult to distinguish from the

black-billed gull The black-billed gull (''Chroicocephalus bulleri''), Buller's gull, or tarāpuka ( Māori) is a Near Threatened species of gull in the family Laridae. This gull is found only in New Zealand, its ancestors having arrived from Australia around 25 ...

. The legs are also brown and there are brown spots on the grey wings.

Distribution

It is the smallest gull commonly seen in New Zealand. The population is estimated at 500,000. It was formerly considered a distinctive species, but looks similar to the

found in Australia, and is now considered to be a subspecies.

Behaviour

Behaviourally, the red-billed gull is a typical gull. It is an aggressive scavenger and

kleptoparasite Kleptoparasitism (etymologically, parasitism by theft) is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, which can mean when foo ...

. Since European settlement its numbers have increased, especially around coastal towns and cities where it can scavenge from urban waste. It normally feeds on small fish, shell fish and worms (from pastures), and sometimes berries, lizards and insects.

Life cycle

They nest from October to December in colonies on the coast, either on islands or rocky headlands, cliffs and beaches. The birds form

pair bond In biology, a pair bond is the strong affinity that develops in some species between a mating pair, often leading to the production and rearing of offspring and potentially a lifelong bond. Pair-bonding is a term coined in the 1940s that is freque ...

s which endure across seasons, but there is a certain amount of

extra-pair copulation Extra-pair copulation (EPC) is a mating behaviour in monogamous species. Monogamy is the practice of having only one sexual partner at any one time, forming a long-term bond and combining efforts to raise offspring together; mating outside this pai ...

. Courtship feeding is an important part of the preparation for mating. Nests are well formed and may be constructed of seaweed, grasses, leaves and ice plants. Generally two to three eggs are laid, their colour ranges from brown to grey with light and dark brown spots all over. The bird generally lives up to 12 years, although individuals have also been found living up to 30 years.

Gallery

File:Red-billed gull portrait, New Brighton, New Zealand 03.jpg, Upper body File:Chroicocephalus scopulinus LC0381.jpg, Adult with chick File:Red-billed Gull in flight.jpg, Red-billed gull in flight File:A balletic Looking Red Billed Gull.jpg, Landing File:Red billed gull-07.jpg, Crouching File:NeuseelandSeagulls.jpg, Second-winter, first-winter, and adult birds (first three, from front) File:Red-billed gull (J).jpg, Juvenile bathing,

Picton, New Zealand Picton ( mi, Waitohi) is a town in the Marlborough Region of New Zealand's South Island. The town is located near the head of the Queen Charlotte Sound / Tōtaranui, north of Blenheim and west of Wellington. Waikawa lies just north-east o ...

File:Red-Billed Gull-Nueva Zelanda2.jpg, Eggs File:Red billed gull-12.jpg, Comparison of adult (left) and immature (right) red-billed gulls in flight File:Red-billed gull colony, Kaikōura, New Zealand 08.jpg, Sea gull colony in Kaikōura File:Red billed gull 2.jpg, alt=2021 photo, 2021 photo

Notes

References

*Mills, J. A. (1994). Extra-pair copulations in the Red-Billed Gull: Females with high-quality, attentive males resist. ''Behaviour, 128'', 41–64. * Pons J.M., Hassanin, A., and Crochet P.A.(2005). ''Phylogenetic relationships within the Laridae (Charadriiformes: Aves) inferred from mitochondrial markers.'' Molecular Phylogenetics and Evolution 37(3):686-699 *Tasker, C. R., & Mills, J. A. (1981). A functional analysis of courtship feeding in the Red-billed Gull, ''Larus Novaehollandiae scopulinus''. ''Behaviour, 77'', 222ff

External links

Red-billed Gull, New Zealand Birds Online
{{Taxonbar, from1=Q76472, from2=Q27608860 red-billed gull Endemic birds of New Zealand red-billed gull Taxa named by Johann Reinhold Forster Subspecies