Editing Galápagos Islands (section)

===Environmental threats===
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Introduced plants and animals, such as feral goats, cats, and cattle, brought accidentally or willingly to the islands by humans, represent the main threat to Galápagos.<ref>{{Cite news|title=The islands that once inspired Charles Darwin struggle to adapt to the coronavirus|url=https://www.latimes.com/world-nation/story/2020-05-11/pandemic-upends-life-on-isolated-idyllic-galapagos-islands|date=11 May 2020|via=[[Los Angeles Times]]|agency=[[Associated Press]]|language=en-US|access-date=29 May 2020}}</ref> Quick to reproduce and with no natural predators, these alien species decimated the habitats of native species. The native animals, lacking natural predators on the islands, are defenseless to introduced predators.

There are over 700 introduced plant species today. There are only 500 native and endemic species. This difference is creating a major problem for the islands and the natural species that inhabit them. These plants have invaded large areas and eliminated endemic species in the humid zones of San Cristobal, Floreana, Isabela and Santa Cruz. Some of the most harmful introduced plants are the guayaba or [[guava]] (''Psidium guajava''), [[avocado]] (''Persea americana''), [[cascarilla]] (''Cinchona pubescens''), [[balsa]] (''Ochroma pyramidale''), [[hill raspberry]] (''Rubus niveus''), various [[citrus]] (orange, [[grapefruit]], lemon), [[floripondio]], higuerilla (''[[Ricinus communis]]'') trees and the elephant grass, ''[[Pennisetum purpureum]]''.

Many species were introduced to the Galápagos by [[pirate]]s. [[Thor Heyerdahl]] quoted documents that mention the [[Viceroy of Peru]], knowing that British pirates ate the goats that they themselves had released in the islands, ordered dogs to be freed there to eliminate the goats.<ref name=Heyerdahl>Heyerdahl, Thor; & Skjolsvold, Arne (1956). "Archaeological Evidence of Pre-Spanish Visits to the Galápagos Islands", Memoirs 12, Society for American Archaeology.</ref> Also, when colonization of Floreana by José de Villamil failed, he ordered the goats, donkeys, cattle and other animals from the farms in Floreana be transferred to other islands for the purpose of later colonization.

The [[black rat]] ({{lang|la|Rattus rattus}}) attacks small Galápagos tortoises when they leave the nest, so in Pinzón they stopped the reproduction for a period of more than 50&nbsp;years; only adults were found on that island.<ref>{{cite journal|author=Nicholls, Henry |title=Invasive species: The 18-km<sup>2</sup> rat trap |journal=Nature |volume=497 |issue=7449 |pages=306–308 |date=15 May 2013 |doi=10.1038/497306a |pmid=23676736 |bibcode=2013Natur.497..306N |doi-access=free }}</ref> Also, where the black rat is found, the endemic rat has disappeared. Cattle and donkeys eat all the available vegetation and compete with native species for scarce water. In 1959, fishermen introduced one male and two female goats to Pinta island; by 1973, the National Park service estimated the population of goats to be over 30,000 individuals. Goats were also introduced to Marchena in 1967 and to Rabida in 1971. A goat eradication program, however, cleared the goats from Pinta and Santiago and most of the goat population from Isabela,<ref>{{Cite web|url=http://www.galapagos.org/conservation/conservation/conservationchallenges/invasive-species/|title=Invasive Species|website=Galapagos Conservancy|access-date=1 June 2016|archive-date=7 June 2016|archive-url=https://web.archive.org/web/20160607143022/http://www.galapagos.org/conservation/conservation/conservationchallenges/invasive-species/|url-status=dead}}</ref> and, by 2006, all [[Feral animal|feral]] pigs, donkeys and [[Judas goat#Goats tracking feral goats|non-sterile goats]] had been eliminated from Santiago and Isabela, the largest islands with the worst problems due to non-native mammals.<ref name="Isabela1">{{cite web | title = Project Isabela | publisher = [[Galapagos Conservancy]] | url = http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/project-isabela/ | access-date = 21 December 2016 }}</ref><ref name="Isabela2">{{cite web | author = John | title =Project Isabela: When Slaughtering 250,000 Goats Meant Saving A Species | publisher = All That Is Interesting   | date = 5 March 2015 | url = http://all-that-is-interesting.com/project-isabela  | access-date = 21 December 2016 }}</ref>

Six species of small non-native vertebrates have established self-sufficient populations in Galápagos and may become invasive: Fowler's snouted tree frog ''[[Scinax quinquefasciatus]]'', common house gecko ''[[Common house gecko|Hemidactylus frenatus]]'', mourning gecko ''[[Lepidodactylus lugubris]]'', dwarf gecko ''[[Gonatodes caudiscutatus]]'', Peters' leaf-toed gecko ''[[Phyllodactylus reissii]]'', and smooth-billed ani ''[[Smooth-billed ani|Crotophaga ani]]''. Domestic fowl ''[[Chicken|Gallus gallus]]'' holds feral populations, which may have self-sufficient populations, but evidence is unclear.<ref>{{Cite journal|last=Cisneros-Heredia|first=Diego F|date=22 February 2018|title=Non-native small terrestrial vertebrates in the Galapagos|journal=PeerJ Preprints|language=en|doi=10.7287/peerj.preprints.26563v1|issn=2167-9843|doi-access=free}}</ref><ref>{{Cite book|title=Understanding Invasive Species in the Galapagos Islands|last=Cisneros-Heredia|first=Diego F.|date=2018|publisher=Springer, Cham|isbn=9783319671765|series=Social and Ecological Interactions in the Galapagos Islands|pages=95–139|language=en|doi=10.1007/978-3-319-67177-2_7|chapter = The Hitchhiker Wave: Non-native Small Terrestrial Vertebrates in the Galapagos}}</ref>

The fast-growing poultry industry on the inhabited islands has been cause for concern from local conservationists, who fear domestic birds could introduce disease into the endemic wild bird populations.

The Galápagos marine sanctuary is under threat from a host of [[illegal fishing]] activities, in addition to other problems of development.<ref name=Carr2013>{{cite journal |author1=Carr, Lindsey A |author2=Stier, Adrian C |author3=Fietz, Katharina |author4=Montero, Ignacio |author5=Gallagher, Austin J |author5-link=Austin Gallagher |author6=Bruno, John F |year=2013 |title=Illegal shark fishing in the Galápagos Marine Reserve |journal=[[Marine Policy]] |volume=39 |pages=317–321 |url=https://blog1.miami.edu/sharklab/wp-content/uploads/sites/28/2018/08/Carr-et-al-2013.pdf |access-date=12 March 2013 |doi=10.1016/j.marpol.2012.12.005 |archive-url=https://web.archive.org/web/20130409152642/http://rjd.miami.edu/assets/pdfs/pubs/Carr%20et%20al%202013.pdf |archive-date=9 April 2013 |url-status=live}}{{cbignore}}</ref> The most pressing threat to the Marine Reserve comes from local, mainland and foreign fishing targeting marine life illegally within the Reserve,<ref>{{Cite web|last=Urbina|first=Ian|date=1 November 2020|title=China's Outlaw Fishermen. Le Monde Diplomatique|url=https://mondediplo.com/2020/11/05fishing|access-date=|website=}}</ref> such as sharks (hammerheads and other species) for their fins,<ref name=Carr2013/> and the harvest of sea cucumbers out of season. Development threatens both land and sea species. The growth of both the tourism industry and local populations fuelled by high birth rates and illegal immigration threaten the wildlife of the Archipelago. The grounding of the oil tanker ''[[Jessica (tanker)|Jessica]]'' in 2001 and the subsequent oil spill brought this threat to world attention.

In 2007, [[UNESCO]] put the Galápagos Islands on their [[List of World Heritage in Danger]] because of threats posed by invasive species, unbridled tourism and overfishing.<ref>{{cite web
|url=https://whc.unesco.org/en/danger/
|title=World Heritage in Danger List
|publisher=UNESCO World Heritage
|access-date=8 August 2007
}}</ref>
On 29 July 2010, the [[World Heritage Committee]] decided to remove the Galápagos Islands from the list because the Committee found significant progress had been made by Ecuador in addressing these problems.<ref>{{cite web
|url=https://whc.unesco.org/en/news/636
|title=World Heritage Committee inscribes the Tombs of Buganda Kings (Uganda) and removes Galápagos Islands (Ecuador)
|publisher=UNESCO World Heritage
|access-date=30 July 2010
}}</ref>

On 28 January 2008, [[Galápagos National Park]] official Victor Carrion announced 53 sea lions (13 [[Pinniped|pups]], 25 youngsters, 9 males and 6 females) were killed at the Galápagos Islands nature reserve on [[Pinta Island|Pinta]], with their heads caved in. In 2001, [[Poaching|poachers]] killed 35 male sea lions.<ref>{{cite news|url=http://news.bbc.co.uk/2/hi/americas/7214860.stm |title=BBC NEWS, Sea lions massacred in Galápagos |work=BBC News |date=29 January 2008 |access-date=23 May 2012}}</ref>

The Galápagos Islands were short-listed as a candidate to be one of the [[New7Wonders of Nature]] by the New7Wonders of Nature Foundation. As of February 2009, the archipelago was ranked first in Group B, the category for islands.<ref>{{Cite web|url=http://www.new7wonders.com/nature/en/liveranking/|archiveurl=https://web.archive.org/web/20090705105855/http://www.new7wonders.com/nature/en/liveranking/|url-status=dead|title=New 7 Wonders of the World: Live Ranking|archivedate=5 July 2009}}</ref>

The islands' biodiversity is under threat from several sources. The human population is growing at a rate of 8% per year (1995). Introduced species have caused damage, and in 1996 a US$5 million, five-year eradication plan commenced in an attempt to rid the islands of introduced species such as goats, rats, deer, and donkeys. Except for the rats, the project was essentially completed in 2006.<ref name="Isabela1" /><ref name="Isabela2" /> Rats have only been eliminated from the smaller Galápagos Islands of [[Rábida Island|Rábida]] and [[Pinzón Island|Pinzón]].<ref name="Isabela3">{{cite web | title = Post-Rat Eradication and Monitoring on Pinzón | publisher = [[Galapagos Conservancy]] | url = http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/rat-eradication/ | access-date = 21 December 2016 | archive-date = 18 December 2016 | archive-url = https://web.archive.org/web/20161218183822/http://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/rat-eradication/ | url-status = dead }}</ref>

[[El Niño]] has adversely affected the marine ecosystem. In January 2001, an oil slick from a stranded tanker threatened the islands, but winds and shifting ocean currents helped disperse the oil before much damage was done. The devastating El Niño of 1982–83 saw almost six times as much rain as normal in the Galapagos and created a wildlife catastrophe.<ref name="Galpagos-Islands">{{cite web | title = Galapagos: El Niño and La Niña | url = https://www.galapagos-islands.com/2018/05/galapagos-el-nino-and-la-nina.html | access-date = 9 November 2018 | archive-date = 9 November 2018 | archive-url = https://web.archive.org/web/20181109070745/https://www.galapagos-islands.com/2018/05/galapagos-el-nino-and-la-nina.html | url-status = dead }}</ref> The 1997–98 El Niño adversely affected wildlife in the waters surrounding the islands, as the waters were {{convert|5|C-change|0}} warmer than normal. Corals and barnacles suffered, hammerhead sharks were driven away, and most of the island's seabirds failed to breed in 1997–98. The mortality rate of marine iguanas rose as the green algae they feed on was replaced by inedible red algae. During the 1982–83 El Niño, 70% of the marine iguanas starved to death because of this.<ref name="Galápagos Islands 2010">"Galápagos Islands" in ''The Hutchinson Unabridged Encyclopedia with Atlas and Weather guide'' (2010). Abington: Helicon.</ref>