Editing Juan Fernández Islands (section)

==Biota and ecology==
The Juan Fernández islands are home to a high percentage of rare and [[endemic (ecology)|endemic]] plants and animals, and are recognized as a distinct [[ecoregion]]. The volcanic origin and remote location of the islands meant that the islands' flora and fauna had to reach the [[archipelago]] from far across the sea; as a result, the island is home to relatively few plant species and very few animal species. The closest relatives of the [[archipelago]]'s plants and animals are found in the [[Temperate broadleaf and mixed forests]] ecoregions of southern South America, including the [[Valdivian temperate rain forests]], [[Magellanic subpolar forests]], and [[Desventuradas Islands]].<ref>{{Cite web |title=Archipiélago de Juan Fernández {{!}} The Endemic Plants of Chile |url=https://chileanendemics.rbge.org.uk/regions/jf |access-date=2025-03-30 |website=chileanendemics.rbge.org.uk}}</ref>

===Flora===
The '''Juan Fernández Islands''' are renowned for their unique and diverse flora, characterized by a high degree of [[endemism]]. The archipelago comprises approximately 361 species of vascular plants, including 53 ferns, 65 monocots, and 243 dicots, spanning 73 families and 219 genera. Notably, there is one endemic family ([[Lactoris|Lactoridaceae]]), 12 endemic genera, and 126 endemic species, resulting in an endemism rate of 11% at the generic level and 60% at the species level.<ref>{{Cite journal |last=Stuessy |first=Tod |last2=Marticorena |first2=Clodomiro |last3=R |first3=Roberto Rodriguez |last4=Crawford |first4=Daniel |last5=O |first5=Mario Silva |date=1992-01-01 |title=Endemism in the Vascular Flora of the Juan Fernandez Islands |url=https://scholarship.claremont.edu/aliso/vol13/iss2/3/ |journal=Aliso: A Journal of Systematic and Floristic Botany |volume=13 |issue=2 |pages=297–307 |doi=10.5642/aliso.19921302.03 |issn=0065-6275|doi-access=free }}</ref>

Vegetation zones on the islands generally correspond to elevation. Grassy slopes with native and introduced species cover much of the lower altitudes of [[Robinson Crusoe Island]] (Isla Más a Tierra) and [[Alejandro Selkirk Island]] (Isla Más Afuera), as well as nearly all of [[Santa Clara Island]]. Tall lowland forests are dominated by the largest trees in the archipelago, including [[Drimys confertifolia]], [[Nothomyrcia|Myrceugenia fernandeziana]] (on Robinson Crusoe Island), and [[Myrceugenia schulzei]] (on Alejandro Selkirk Island). All three of these species are endemic to the [[ecoregion]] and considered vulnerable.<ref>{{Cite web |date=2022-07-29 |title=Juan Fernández Islands Temperate Forests |url=https://www.oneearth.org/ecoregions/juan-fernandez-islands-temperate-forests/ |access-date=2025-03-30 |website=One Earth |language=en}}</ref><ref>{{Cite web |last=Griemler |first=Josef |date=1 July 2002 |title=The Vegetation of Robinson Crusoe Island |url=https://scholarspace.manoa.hawaii.edu/server/api/core/bitstreams/605a34e5-0de7-48be-8ba2-15d69e1fffda/content |access-date=30 March 2025 |website=Scholar Space}}</ref>

In the [[Montane ecosystem|montane]] forests of Robinson Crusoe Island, the understory is notably composed of tree ferns such as [[Thyrsopteris|Thyrsopteris elegans]], which form dense forests at elevations around 700 to 750 meters. These forests also include species like [[Blechnaceae|Dicksonia berteroana]] and various [[Blechnum]] species. The dominant tree species in these montane forests include [[Genus|endemic genera]] such as [[Cuminia]], [[Zanthoxylum|Fagara]], and [[Rhaphithamnus]].<ref name=":1">{{Cite web |title=Rescuing and restoring the native flora of Robinson Crusoe Island |url=https://www.cabi.org/projects/rescuing-and-restoring-the-native-flora-of-robinson-crusoe-island/ |access-date=2025-03-30 |website=CABI.org |language=en-GB}}</ref>

The flora of the '''Juan Fernández Islands''' has been significantly impacted by invasive plant species. On Robinson Crusoe Island, invasive species such as wild blackberry (''[[Rubus ulmifolius]]'') and maqui (''[[Aristotelia chilensis]]'') have colonized 80–90% of the native forest, exerting tremendous pressure on the remaining tracts of forest and the animals that depend on it.<ref name=":1" />

{{see also|List of endemic plants of the Juan Fernández Islands}}

<gallery align="center" caption="Maps and satellite images of the islands">
File:Rob-cru.png|Map of Robinson Crusoe Island (including Santa Clara Island)
File:Isla mas Afuera Juan Fernandez (Chili).jpg|Map of Alejandro Selkirk Island
File:Juan fernandez 1927.jpg|Map of both islands
File:Robinson Crusoe.JPG|Satellite images of Juan Fernández Islands (Alejandro Selkirk Island, inset left)
File:CL Pacific islands.PNG|overview map
</gallery>

===Fauna===
The Juan Fernández Islands have a very limited fauna, with no native land [[mammal]]s, [[reptile]]s, or [[amphibia]]ns. Seventeen land and sea-bird species breed on the islands. The island has three endemic bird species, and three endemic subspecies. Introduced fauna by humans include [[rat]]s and [[goat]]s. [[Robinson Crusoe Island]] is home to an endemic and endangered [[hummingbird]], the [[Juan Fernández firecrown]] (''Sephanoides fernandensis''). This large [[hummingbird]], about {{convert|11|cm|0|abbr=on}} long, is thought to number only about 500 individuals. The other endemic bird species are the [[Juan Fernández tit-tyrant]] (''[[Anairetes]] fernandezianus'') of Robinson Crusoe Island, and the [[Masafuera rayadito]] (''Aphrastura masafuerae'') of Alejandro Selkirk Island.<ref>{{Cite web|url=http://tropicalconservationscience.mongabay.com/content/v7/TCS-2014-Vol7(4)_677-689_Gonzalez.pdf|title=Gonzalez J. (2014). Phylogenetic position of the most endangered Chilean bird: the Masafuera Rayadito (''Aphrastura masafuerae''; Furnariidae). ''Tropical Conservation Science''. 7:677–689.}}</ref> The islands support the entire known breeding populations of two petrel species, [http://www.birdlife.org/datazone/speciesfactsheet.php?id=3892 Stejneger's Petrel] ''Pterodroma longirostris'' ([http://www.redlist.org IUCN] status VU) and the [http://www.birdlife.org/datazone/speciesfactsheet.php?id=3899 Juan Fernandez Petrel] ''Pterodroma externa'' ([http://www.redlist.org IUCN] status VU). In addition, the Juan Fernandez Islands may still support a third breeding petrel species, [http://www.birdlife.org/datazone/speciesfactsheet.php?id=3891 De Filippi's Petrel] ''Pterodroma defilippiana'' ([http://www.redlist.org IUCN] status VU), whose only other known breeding grounds are on the [[Desventuradas Islands]]. The [[Magellanic penguin]] breeds on Robinson Crusoe Island within the [[archipelago]].<ref>Hogan, C. Michael (2008) [http://globaltwitcher.auderis.se/artspec_information.asp?thingid=232 "Magellanic Penguin"]. Global Twitcher. Retrieved 5 March 2010.</ref> All three islands of the Juan Fernandez archipelago have been recognised as [[Important Bird Area]]s (IBAs) by [[BirdLife International]].<ref name=bli>{{cite web |url=http://datazone.birdlife.org/site/factsheet/parque-nacional-archipiélago-de-juan-fernández:-islas-robinson-crusoe-and-santa-clara-iba-chile|title= Islas Robinson Crusoe and Santa Clara|author=<!--Not stated--> |date=2021|website= BirdLife Data Zone|publisher= BirdLife International|access-date= 22 January 2021}}</ref>

The endemic Juan-Fernandez spiny lobster (without claws) lives in the marine waters (''[[Jasus frontalis]]''). The [[Juan Fernández fur seal]] (''Arctophoca philippii'') also lives on the islands. This species was nearly exterminated in the sixteenth to nineteenth century, but it was rediscovered in 1965. A census in 1970 found about 750 [[fur seal]]s living there. Only two were sighted on the [[Desventuradas Islands]], located some {{convert|780|km|mi|0|abbr=on}} to the north. The actual population of the Desventuradas may be higher, because the species tends to hide in sea caves. There seems to be a yearly population increase of 16–17 percent.