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
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 ...
found in
Australia, and is now considered to be a
subspecies.
Behaviour
![Red billed gull eating berries 02](https://upload.wikimedia.org/wikipedia/commons/4/41/Red_billed_gull_eating_berries_02.jpg)
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