Editing Kiritimati (section)

== Ecology ==
The [[flora (plants)|flora]] and the [[fauna (animals)|fauna]] consist of [[taxa]] adapted to drought. [[Terrestrial animal|Terrestrial]] fauna is scant; there are no truly native land [[mammal]]s and only one native land bird<ref>In the strict sense, i.e. excluding the [[wikt:Special:Search/amphibious|amphibious]] [[eastern reef egret]]</ref> – Kiribati's [[endemism|endemic]] [[Acrocephalus (bird)|reed-warbler]], the [[bokikokiko]] (''Acrocephalus aequinoctialis''). The 1957 attempt to introduce the [[Endangered species|endangered]] [[Rimitara lorikeet]] (''Vini kuhlii'') has largely failed; a few birds seem to linger on, but the lack of abundant [[coconut palm]] forest, on which this tiny parrot depends, makes Kiritimati a suboptimal habitat for this [[species]].

[[File:Scaevola taccada flowers.JPG|thumb|left|Flowers of beach naupaka (''[[Scaevola taccada]]''), Kiritimati's most typical woody plant.]]

=== Flora ===
The natural vegetation on Kiritimati consists mostly of low [[shrubland]] and [[grassland]]. What little woodland exists is mainly open [[coconut|coconut palm]] (''Cocos nucifera'') plantation. There are three small woods of catchbird trees (''[[Pisonia grandis]]''), at Southeast Point, Northwest Point, and on Motu Tabu. The latter was planted there in recent times. About 50 [[Introduced species|introduced]] plant [[species]] are found on Kiritimati; as most are plentiful around settlements, former military sites and roads, it seems that these only became established in the 20th century.<ref name = teebaki1993 />

[[File:Starr 010520-0073 Tournefortia argentea.jpg|thumb|right|Tree heliotrope (''[[Heliotropium foertherianum]]'') in typical habitat on a [[Hawaiian Islands|Hawaiian island]].]]
Beach naupaka (''[[Scaevola taccada]]'') is the most common [[shrub]] on Kiritimati; beach naupaka scrub dominates the vegetation on much of the island, either as pure stands or interspersed with tree heliotrope (''[[Heliotropium foertherianum]]'') and bay cedar (''[[Suriana|Suriana maritima]]''). The latter species is dominant on the drier parts of the lagoon flats where it grows up to {{convert|2|m|ft|abbr=on}} tall. Tree heliotrope is most commonly found a short distance from the sea- or lagoon-shore. In some places near the seashore, a low vegetation dominated by Polynesian heliotrope (''[[Heliotropium anomalum]]''), yellow purslane (''[[Portulaca lutea]]'') and common purslane (''[[Portulaca oleracea|P. oleracea]]'') is found. In the south and on the sandier parts, ''[[Sida fallax]]'', also growing up to 2 m tall, is abundant. On the southeastern peninsula, ''S. fallax'' grows more stunted, and Polynesian heliotrope, yellow and common purslane as well as the [[Boerhavia|spiderling]] ''[[Boerhavia repens]]'', the [[Parasitic plant|parasitic]] [[vine]] ''[[Cassytha filiformis]]'', and Pacific Island thintail (''[[Lepturus repens]]'') supplement it. The last species dominates in the coastal grasslands. The wetter parts of the lagoon shore are often covered by abundant growth of shoreline purslane (''[[Sesuvium portulacastrum]]'').<ref name = teebaki1993 />

Perhaps the most destructive of the recently introduced plants is sweetscent (''[[Pluchea odorata]]''), a [[Pluchea|camphorweed]], which is considered an [[Invasive species|invasive weed]] as it overgrows and displaces herbs and grasses. The introduced creeper ''[[Tribulus cistoides]]'', despite having also spread conspicuously, is considered to be more beneficial than harmful to the [[ecosystem]], as it provides good nesting sites for some [[seabird]]s.<ref name = teebaki1993 />

===Birds===
[[File:Sterna fuscata flight.JPG|thumb|upright|Despite massive declines in recent decades, more [[sooty tern]]s continue to nest on Kiritimati than anywhere else in the world.]]
[[File:Xmas shearwaters roosting.jpg|thumb|right|The [[Christmas shearwater]] was named after Kiritimati.]]
[[File:Red-footed Boobies.jpg|thumb|right|White-[[polymorphism (biology)|morph]] [[red-footed booby|red-footed boobies]]. Those on Kiritimati will reuse nests for several years, unlike in most other colonies.]]

:''See also "Extinction" [[#Extinction|below]].''

More than 35&nbsp;bird [[species]] have been recorded from Kiritimati. As noted above, only the [[bokikokiko]] (''Acrocephalus aequinoctialis''), perhaps a few [[Rimitara lorikeet]]s (''Vini kuhlii'') – if any remain at all – and the occasional [[eastern reef egret]] (''Egretta sacra'') make up the entire landbird fauna. About 1,000&nbsp;adult bokikokikos are to be found at any date, but mainly in mixed grass/shrubland away from the settlements.<ref name=teebaki1993/>

On the other hand, [[seabird]]s are plentiful on Kiritimati, and make up the bulk of the breeding bird population. There are 18&nbsp;species of seabirds breeding on the island, and Kiritimati is one of the most important breeding grounds anywhere in the world for several of these:<ref name=teebaki1993/>

[[Phaethontiformes]]
* Eastern [[red-tailed tropicbird]] (''Phaethon rubricauda melanorhynchus''{{efn|name=doubtful-ssp|Validity of subspecies disputed.}}) – important breeding colony; 8,000&nbsp;birds before the 1982–1983 decline, fewer than 3,000 in 1984

[[Charadriiformes]]
* Micronesian [[black noddy]] (''Anous minutus marcusi'') – 20,000&nbsp;birds before the 1982–1983 decline
* [[Little white tern]] (''Gygis microrhyncha''{{efn|Usually described as a sub-species ''[[Gygis alba]] microrhyncha''}}) – 8,000&nbsp;birds before the 1982–1983 decline
* Central Pacific [[sooty tern]] (''Onychoprion fuscatus oahuensis''{{efn|name=doubtful-ssp}}) – largest breeding colony in the world; around 7,000,000&nbsp;birds before the 1982–1983 decline
* [[Spectacled tern]] (''Onychoprion lunatus'') – important breeding colony; 6,000&nbsp;birds before the 1982–1983 decline
* Central [[blue-grey noddy]] (''Procelsterna cerulea cerulea'') – important breeding colony, possibly the largest worldwide of this subspecies; 4,000&nbsp;birds before the 1982–1983 decline

[[Procellariiformes]]
* [[Polynesian storm petrel]] (''Nesofregetta fuliginosa'') – important breeding colony; 1,000&nbsp;birds before the 1982–1983 decline
* [[Phoenix petrel]] (''Pterodroma alba'') – largest breeding colony in the world; 24,000&nbsp;birds before the 1982–1983 decline
* [[Christmas shearwater]] (''Puffinus nativitatis'') – largest [[subpopulation]] worldwide on Motu&nbsp;Upua; 12,000&nbsp;birds before the 1982–1983 decline
* [[Wedge-tailed shearwater]] (''Puffinus pacificus''<ref name=Penhallurick/>) – among the very largest breeding colonies in the world; about 1,000,000&nbsp;birds before the 1982–1983 decline

[[Pelecaniformes]]
* Indopacific [[lesser frigatebird]] (''Fregata ariel ariel'') – important breeding colony; 9,000&nbsp;birds before the 1982–1983 decline
* Central Pacific [[great frigatebird]] (''Fregata minor palmerstoni''{{efn|name=doubtful-ssp}}) – important breeding colony; 12,000&nbsp;birds before the 1982–1983 decline, 6,500 afterwards
* Austropacific [[masked booby]] (''Sula dactylatra personata'') – important breeding colony; 3,000&nbsp;birds before the 1982–1983 decline
* Indopacific [[red-footed booby]] (''Sula sula rubripes''{{efn|name=doubtful-ssp}}) – 12,000&nbsp;birds before the 1982–1983 decline

Kiritimati's lagoon and the saltflats are a prime location for [[migratory bird]]s to stop over or even stay all winter. The most commonly seen migrants are [[ruddy turnstone]] (''Arenaria interpres''), [[Pacific golden plover]] (''Pluvialis fulva''), [[bristle-thighed curlew]] (''Numenius tahitiensis''), and [[wandering tattler]] (''Tringa incana''); other [[seabird]]s, [[wader]]s, and even [[dabbling duck]]s can be encountered every now and then.<ref name=teebaki1993/> Around 7&nbsp;October (±5&nbsp;days), some 20&nbsp;million sooty shearwaters pass through here en route from the North Pacific feeding grounds to breeding sites around [[New Zealand]].<ref>
{{cite journal
 |last1=Shaffer |first1=Scott A.
 |title=Migratory shearwaters integrate oceanic resources across the Pacific Ocean in an endless summer
 |journal=[[Proceedings of the National Academy of Sciences]]
 |date=2006
 |volume=103 |issue=34 |pages=12799–12802
 |doi=10.1073/pnas.0603715103
 |pmid=16908846
 |pmc=1568927
 |bibcode=2006PNAS..10312799S
 |url=https://cloudfront.escholarship.org/dist/prd/content/qt71h247bh/qt71h247bh.pdf
|doi-access=free
 }}
</ref>

===Other fauna===
The only mammals native to the region are the common [[Polynesian rat]] (''Rattus exulans'') and the goats. The rat seems to have been introduced by seafarers many centuries before Cook arrived in 1777 (he mentioned them already being present); goats have been extinct since 14&nbsp;January 2004. [[Black rat]]s (''Rattus rattus'') were present at some time, perhaps introduced by 19th-century sailors or during the nuclear tests. They were not able to gain a foothold between [[predation]] by cats and [[competitive exclusion]] by Polynesian rats, and no black rat population is found on Kiritimati today.<ref name=teebaki1993/>

Up to 2,000&nbsp;[[feral cat]]s can in some years be found on the island; the population became established in the 19th&nbsp;century. Their depredations seriously harm the birdlife. Since the late 19th&nbsp;century,<ref name=streets1877/> they have driven about 60% of the seabird species from the mainland completely, and during particular dry spells they will cross the mudflats and feast upon the birds on the ''motu''s. [[Spectacled tern]] chicks seem to be a favourite food of the local cat population. There are some measures being taken to ensure the cat population does not grow. That lowering the cat population by some amount would much benefit Christmas and its inhabitants is generally accepted, but the situation is too complex to simply go and eradicate them outright. A limited population of [[feral pigs]] exists. They were once plentiful and wreaked havoc especially on the ''[[Onychoprion]]'' and [[Anous|noddies]]. [[Boar hunting|Pig hunting]] by locals has been encouraged, and was highly successful at limiting the pig population to a sustainable level, while providing a source of cheap protein for the islanders.<ref name=teebaki1993/>

[[File:Lepidodactylus lugubris.jpg|thumb|left|[[Mourning gecko]], a common sight all over the tropical Pacific]]
[[File:Coenobita perlatus.jpg|thumb|right|A [[strawberry land hermit crab]] in its shell]]
There are some [[supertramp (ecology)|"supertramp"]] [[lizard]]s which have reached the island by their own means. Commonly seen are the [[mourning gecko]] (''Lepidodactylus lugubris'') and the [[skink]] ''[[Cryptoblepharus boutonii]]''; the [[four-clawed gecko]] (''Gehyra mutilata'') is seen less often.<ref name=teebaki1993/>

There are some [[crustacean]]s of note to be found on Kiritimati and in the waters immediately adjacent. The [[wikt:Special:Search/amphibious|amphibious]] [[coconut crab]] (''Birgus latro'') is not as common as on [[Teraina]]. [[Ghost crab]]s ([[genus]] ''Ocypode''), ''[[Cardisoma carnifex]]'' and ''[[Geograpsus grayi]]'' [[land crab]]s, the [[strawberry land hermit crab]] (''Coenobita perlatus'') are also notable.<ref name=teebaki1993/> Introduced brine shrimp ''[[Artemia salina]]'' populate the island's saline ponds.<ref name=teebaki1993/>