Editing Biscayne National Park (section)

===Keys===
[[File:Totten Key.jpg|thumb|alt=Aerial view of island and forest|Totten Key and reefs]]
[[File:Consolea corallicola.jpg|thumb|alt=Close-up of flowering cactus pads|The semaphore prickly-pear cactus is only found in and near Biscayne National Park and may be the rarest plant in the U.S.]]
Elliott Key is the largest island in the park, measuring {{convert|1650|acre|abbr=on}} and about {{convert|8.1|mi|0|abbr=on}} long by {{convert|0.62|mi|0|abbr=on}} wide. Next largest is Old Rhodes Key at {{convert|660|acre|abbr=on}}, then Sands Key {{convert|420|acre|abbr=on}}, Totten Key {{convert|380|acre|abbr=on}} and Little Totten Key at {{convert|200|acre|abbr=on}}, with 37 smaller islands arranged in a north–south line {{convert|5|to|8.7|mi|0|abbr=on}} east of the mainland shoreline.<ref name="npca21" /> The keys shift from barrier islands with rocky cores in the north to coral rock platforms in the south. All are fringed with mangroves, with subtropical vegetation and hardwood forests in the interiors, including [[gumbo limbo]], [[mahogany]], [[ironwood]], [[Amyris elemifera|torchwood]] and [[Chrysophyllum oliviforme|satinleaf]]. Insects include [[Schaus' swallowtail]], an endangered species, as well as dense clouds of mosquitoes in the wet season, preyed upon by dragonflies. [[Marsh rabbit]]s and [[raccoons]], together with mice and rats comprise the primary mammalian species. Reptiles include [[rattlesnake]]s and a variety of lizards, as well as an occasional crocodile.<ref name=npsbisc19>{{cite web|title=Florida Keys|url=http://www.nps.gov/bisc/naturescience/keys.htm|work=Biscayne National Park|publisher=National Park Service|access-date=22 November 2012}}</ref>

The keys are a transitional area capable of hosting unexpected birds, often Caribbean species that have strayed near the mainland. The interior of the keys are frequented by warblers and the hawks that prey on them. Coastal zones are habitat for [[ruddy turnstone]]s and [[least sandpiper]]s. Gulls and terns include [[royal tern]]s, [[laughing gull]]s and [[ring-billed gull]]s, with [[brown pelican]]s just offshore. [[Wilson's plover]]s nest on Boca Chita Key, where nesting zones are closed during breeding season.<ref name=npsbisc28/>

Sea turtles nest on island beaches in the park. Park staff actively assist turtle nesting by removing debris from beaches that might pose an obstacle to adults and hatchlings. [[Loggerhead turtle]]s are the most common sea turtle species and account for nearly all of the turtle nests in the park.<ref name=npsbisc37>{{cite web|title=Species Focus: Loggerhead Sea Turtles|url=http://www.nps.gov/bisc/naturescience/species-focus-loggerhead-sea-turtles.htm|work=Biscayne National Park|publisher=National Park Service|access-date=26 November 2012}}</ref> Nest sites are identified by daily morning beach patrols and are protected with mesh screen against the predation by abundant raccoon population. Nest protection efforts have reduced predation from 100% of nests disturbed per year to no disturbed nests in 2007, with a more usual average of more than 50% nest disturbance in most years.<ref name=npsbisc38>{{cite web|title=Sea Turtle Conservation Program|url=http://www.nps.gov/bisc/naturescience/sea-turtle-conservation-program.htm|work=Biscayne National Park|publisher=National Park Service|access-date=26 November 2012}}</ref> In 2012 one undisturbed nest was found and protected, five partially disturbed nests were protected, and one nest was destroyed by predators.<ref name=npsbisc36>{{cite web|title=Summary of 2012 sea turtle nesting season and habitat restoration activity|url=http://www.nps.gov/bisc/naturescience/2012-sea-turtle-conservation-efforts.htm|work=Biscayne National Park|publisher=National Park Service|access-date=26 November 2012}}</ref> The threatened [[eastern indigo snake]] is also present on the island.<ref name=npca22>NPCA, p. 22</ref>

Rare and endangered plant species on the islands include [[Pseudophoenix sargentii|Sargent's cherry palm]] and the semaphore prickly-pear cactus (''[[Consolea corallicola]]''). The cactus, which has been described as "near extinction",<ref name=fna1>{{cite book|title=Consolea corallicola, Flora of North America North of Mexico|url=http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242415229|publisher=Flora of North America Association|access-date=29 January 2013|volume=4: Magnoliophyta|page=150}}</ref> has been reduced to about 20 individuals. A [[Clonal colony|colonial]] population of 570 cacti were found on one island in Biscayne Bay in 2001,<ref name="npsbisc40 Plants">{{cite web|title=Plants|url=http://www.nps.gov/bisc/naturescience/plants.htm|work=Biscayne National Park|publisher=National Park Service|access-date=26 November 2012}}</ref> making it the largest known population of semaphore prickly-pear cactus in the world.<ref name=npsbisc41>{{cite web|title=Cacti / Desert Succulents|url=http://www.nps.gov/bisc/naturescience/cacti.htm|work=Biscayne National Park|publisher=National Park Service|access-date=26 November 2012}}</ref> The only natural population of Sargent's palm grows on Elliott Key. Fewer than 50 grew on the key in 1991. Despite efforts to propagate the plant, there are now 16 Sargent's palms on Elliott Key, with about 123 propagated on Long Key.<ref name="npsbisc40 Plants"/>

Two critically endangered butterflies, [[Papilio aristodemus|Schaus' swallowtail]] (''Papilio aristodemus'') and the [[Miami blue]], are found in the park, mostly on Elliott Key. In 2012 the [[U.S. Fish and Wildlife Service]] (USFWS) authorized a capture and captive breeding program for Schaus' swallowtail after only five of the butterflies were found by surveyors in the park, down from 35 in 2011, of a total surveyed Florida population of 41.<ref name=npsbisc202>{{cite web|title=Schaus Swallowtail Emergency|url=http://www.nps.gov/bisc/parknews/schaus-swallowtail-emergency.htm|work=Biscayne National Park|publisher=National Park Service|date=June 13, 2012|access-date=13 March 2013}}</ref>  The Miami blue was feared to be extinct after Hurricane Andrew in 1992, but a population was found in 1999 at [[Bahia Honda Key]]. Captive breeding produced 25,000 Miami blues, some of which have been released on Elliott Key with mixed results.<ref name=npsbisc201>{{cite web|title=Miami Blue Butterflies Reintroduced|url=http://www.nps.gov/bisc/parknews/miami-blue-butterflies-reintroduced.htm|work=Biscayne National Park|publisher=National Park Service|date=September 18, 2006|access-date=13 March 2013}}</ref>