View source for Manatee

{{short description|Genus of mammals}}
{{About|the aquatic mammal}}
{{pp|small=yes}}
{{Automatic taxobox
| fossil_range = [[Pleistocene|Early Pleistocene]] – [[Holocene|Recent]]<br/>{{fossil range|2.5|0|ref=<ref>{{cite web |publisher=Fossilworks.org |title=''Trichechus'' Linnaeus 1758 (manatee) |url=https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=36903 |access-date=2021-12-17 |archive-date=2023-06-05 |archive-url=https://web.archive.org/web/20230605233924/http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=36903 |url-status=live }}</ref>}}
| name = Manatees
| image = Trichechus Diversity.jpg
| image_caption = Clockwise from upper left: [[West Indian manatee]], [[Amazonian manatee]], [[African manatee]]
| parent_authority =
| taxon = Trichechus
| authority = [[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]]
| type_species = ''[[Trichechus manatus]]''
| type_species_authority = [[Carl Linnaeus|Linnaeus]], 1758
| subdivision_ranks = [[Species]]
| subdivision = * ''[[Trichechus hesperamazonicus]]''&nbsp;[[extinct|†]]
* ''[[Amazonian manatee|Trichechus inunguis]]''
* ''[[West Indian manatee|Trichechus manatus]]''
* ''[[African manatee|Trichechus senegalensis]]''
* ''[[Dwarf manatee|Trichechus "pygmaeus"]]'' (validity questionable)
| synonyms = * ''Halipaedisca'' {{small|Gistel 1848}}
* ''Manatus'' {{small|Brunnich 1772}}
* ''Neodermus'' {{small|Rafinesque 1815}}
* ''Oxystomus'' {{small|Fischer von Waldheim 1803}}
}}
'''Manatees''' ({{IPAc-en|ˈ|m|ae|n|@|t|i:|z}}, [[family (biology)|family]] [[Trichechidae]], [[genus]] '''''Trichechus''''') are large, fully aquatic, mostly [[herbivory|herbivorous]] [[marine mammal]]s sometimes known as '''sea cows'''. There are three accepted living species of Trichechidae, representing three of the four living species in the order [[Sirenia]]: the [[Amazonian manatee]] (''Trichechus inunguis''), the [[West Indian manatee]] (''Trichechus manatus''), and the [[West African manatee]] (''Trichechus senegalensis''). They measure up to {{convert|4.0|m|ftin}} long, weigh as much as {{convert|590|kg}},<ref>[http://kids.nationalgeographic.com/kids/animals/creaturefeature/west-indian-manatee/ West Indian Manatee Facts and Pictures – National Geographic Kids] {{Webarchive|url=https://web.archive.org/web/20110626181256/http://kids.nationalgeographic.com/kids/animals/creaturefeature/west-indian-manatee/ |date=2011-06-26 }}. Kids.nationalgeographic.com. Retrieved on 2011-12-03.</ref> and have paddle-like tails.
Manatees are [[Herbivory|herbivores]] and eat over 60 different freshwater and saltwater plants. Manatees inhabit the shallow, [[marsh]]y coastal areas and rivers of the [[Caribbean Sea]], the [[Gulf of Mexico]], the [[Amazon basin]], and [[West Africa]].
The main causes of death for manatees are human-related issues, such as [[habitat destruction]] and human objects. Their slow-moving, curious nature has led to violent collisions with propeller-driven boats and ships. Some manatees have been found with over 50 scars on them from propeller blades. Natural causes of death include adverse temperatures, predation by crocodiles on young, and disease.
== Etymology ==
The etymology of the name is unclear, with connections having been made to [[Latin language|Latin]] {{lang|la|manus}} "hand" and to [[Carib language|Carib]] ''[[wikt:manaty|manaty]]'' "breast".<ref>{{cite web|last1=Winger|first1=Jennifer|title=What's in a name? Manatees and Dugongs|url=http://nationalzoo.si.edu/Animals/Whats_in_a_name/default.cfm?id=37|department=[[National Zoological Park (United States)|National Zoological Park]]|publisher=Friends of the National Zoo|access-date=19 June 2015|archive-url=https://web.archive.org/web/20051230020729/http://nationalzoo.si.edu/Animals/Whats_in_a_name/default.cfm?id=37|archive-date=30 December 2005|date=2000}}</ref> The term ''sea cow'' is a reference to the species' slow, peaceful, herbivorous nature, reminiscent of that of [[bovine]]s.<ref>{{Cite book|title=Encyclopedia of Animals|last1=Walters|first1=Martin|last2=Johnson|first2=Jinny|publisher=Marks and Spencer |year=2003|isbn=1-84273-964-6|page=229}}</ref>
==Taxonomy==
Manatees are three of the four living species in the order [[Sirenia]]. The fourth is the [[Eastern Hemisphere]]'s [[dugong]]. The Sirenia are thought to have evolved from four-legged land mammals more than 60 million years ago, with the closest living relatives being the [[Proboscidea]] ([[elephant]]s) and Hyracoidea ([[hyrax]]es).<ref>Domning, D.P., 1994, "Paleontology and evolution of sirenians: Status of knowledge and research needs", in ''Proceedings of the 1st International Manatee and Dugong Research Conference'', Gainesville, Florida, 1–5</ref>
==Description==
[[File:Manatee skeleton with calf.jpg|thumb|left|A skeleton of a manatee and calf, the [[Museum of Osteology]], [[Oklahoma City]]]]
[[File:West Indian Manatee Skull.jpg|thumb|left|Skull of a West Indian manatee, the Museum of Osteology, Oklahoma City]]
Manatees weigh {{convert|400|to|550|kg|lb|abbr=on}}, and average {{convert|2.8|to|3.0|m|ftin|abbr=on}} in length, sometimes growing to {{convert|4.6|m|ftin|abbr=on}} and {{convert|1775|kg|lb|abbr=on}} and females tend to be larger and heavier than males. At birth, baby manatees weigh about {{convert|30|kg|lb|abbr=on}} each. The female manatee has two teats, one under each flipper,<ref>{{cite web|url=http://www.amyhremleyfoundation.org/php/education/impacts/Manatee.php|title=The Florida Manatee (''Trichechus manatus latirostrus'')|publisher=The Amy H Remley Foundation|access-date=August 15, 2013|archive-url=https://web.archive.org/web/20140222212950/http://www.amyhremleyfoundation.org/php/education/impacts/Manatee.php|archive-date=February 22, 2014|url-status=dead}}</ref> a characteristic that was used to make early links between the manatee and elephants.
The lids of manatees' small, widely spaced eyes close in a circular manner. The manatee has a large, flexible, [[prehensility|prehensile]] upper lip, used to gather food and eat and for social interaction and communication. Manatees have shorter snouts than their fellow [[sirenia]]ns, the [[dugong]]s.
{{Anchor|Teeth}}
Manatee adults have no [[incisor]] or [[canine tooth|canine]] teeth, just a set of cheek teeth, which are not clearly differentiated into [[Molar (tooth)|molars]] and [[premolar]]s. These teeth are [[polyphyodont|repeatedly replaced throughout life]], with new teeth growing at the rear as older teeth fall out from farther forward in the mouth, somewhat as [[elephant]]s' teeth do.<ref>{{Cite book|editor=Shoshani, J.|year=2000|title=Elephants: Majestic Creatures of the Wild|publisher=Checkmark Books|isbn=0-87596-143-6}}</ref><ref name="EoM"/> At any time, a manatee typically has no more than six teeth in each jaw of its mouth.<ref name=EoM/>
The manatee's tail is paddle-shaped, and is the clearest visible difference between manatees and dugongs; a dugong tail is fluked, similar in shape to that of a whale.
The manatee is unusual among [[mammals]] in having just six [[cervical vertebrae]],<ref>{{cite journal|last1=Hautier|first1=Lionel|journal=PNAS|year=2010|volume=107|issue=44|pages=18903–18908|pmid=20956304|last2=Weisbecker|first2=V|last3=Sánchez-Villagra|first3=M. R.|last4=Goswami|first4=A|last5=Asher|first5=R. J.|title=Skeletal development in sloths and the evolution of mammalian vertebral patterning|doi=10.1073/pnas.1010335107|pmc=2973901|bibcode=2010PNAS..10718903H|doi-access=free}}</ref> a number that may be due to mutations in the [[homeotic genes]].<ref>{{cite web|title=Sticking Their Necks out for Evolution: Why Sloths and Manatees Have Unusually Long (or Short) Necks|url=https://www.sciencedaily.com/releases/2011/05/110505212314.htm|work=May 6th 2011|publisher=Science Daily|access-date=25 July 2013|archive-date=26 April 2019|archive-url=https://web.archive.org/web/20190426223708/https://www.sciencedaily.com/releases/2011/05/110505212314.htm|url-status=live}}</ref> All other mammals have seven cervical vertebrae,<ref>{{cite journal |pmid=10327647 |author=Frietson Galis |year=1999 |title=Why do almost all mammals have seven cervical vertebrae? Developmental constraints, Hox genes and Cancer |journal=Journal of Experimental Zoology |url=http://wwworm.biology.uh.edu/evodevo/lecture11/galis99.pdf |archive-url=https://web.archive.org/web/20041110200159/http://wwworm.biology.uh.edu/evodevo/lecture11/galis99.pdf |url-status=dead |archive-date=2004-11-10 |volume=285 |issue=1 |pages=19–26 |doi=10.1002/(SICI)1097-010X(19990415)285:1<19::AID-JEZ3>3.0.CO;2-Z |bibcode=1999JEZ...285...19G }}</ref> other than the [[two-toed sloth|two-toed]] and [[three-toed sloth]]s.
Like the [[horse]], the manatee has a simple stomach, but a large [[cecum]], in which it can digest tough plant matter. Generally, the intestines are about 45 meters, unusually long for an animal of the manatee's size.<ref>{{Cite web|title=Manatee Anatomy Facts|url=http://manatipr.org/wp-content/uploads/2014/08/SMC-ManateeAnatomyFacts.pdf|access-date=2021-12-24|archive-date=2021-12-26|archive-url=https://web.archive.org/web/20211226175025/http://manatipr.org/wp-content/uploads/2014/08/SMC-ManateeAnatomyFacts.pdf|url-status=live}}</ref>
=== Evolution ===
Fossil remains of manatee ancestors - also known as [[sirenia]]ns - date back to the [[Eocene|Early Eocene]].<ref name=":0">{{Cite book|title=Ecology and Conservation of the Sirenia : Dugongs and Manatees.|last=Marsh, Helene.|date=2011|publisher=Cambridge University Press|others=O'Shea, Thomas J., Reynolds III, John E.|isbn=978-1-139-15887-9|location=Cambridge|oclc=782876868}}</ref><ref>{{Cite journal|last1=de Souza|first1=Érica Martinha Silva|last2=Freitas|first2=Lucas|last3=da Silva Ramos|first3=Elisa Karen|last4=Selleghin-Veiga|first4=Giovanna|last5=Rachid-Ribeiro|first5=Michelle Carneiro|last6=Silva|first6=Felipe André|last7=Marmontel|first7=Miriam|last8=dos Santos|first8=Fabrício Rodrigues|last9=Laudisoit|first9=Anne|last10=Verheyen|first10=Erik|last11=Domning|first11=Daryl P.|date=2021-02-11|title=The evolutionary history of manatees told by their mitogenomes|journal=Scientific Reports|language=en|volume=11|issue=1|pages=3564|doi=10.1038/s41598-021-82390-2|pmid=33574363|issn=2045-2322|pmc=7878490|bibcode=2021NatSR..11.3564D}}</ref> It is thought that they reached the isolated area of the South American continent and became known as [[Trichechidae]]. In the [[Late Miocene]], [[Trichechidae|trichechids]] were likely restricted in South American coastal rivers and they fed on many freshwater plants. [[Dugong]]s inhabited the West Atlantic and Caribbean waters and fed on [[seagrass meadow]]s instead. As the sea grasses began to grow, manatees adapted to the changing environment by growing supernumerary molars. Sea levels lowered and increased erosion and silt runoff was caused by [[glaciation]]. This increased the tooth wear of the bottom-feeding manatees.<ref>{{Cite journal|title=Evolution of Manatees: A Speculative History|url=https://www.jstor.org/stable/1304394|journal=Journal of Paleontology|jstor = 1304394|last1 = Domning|first1 = Daryl P.|year = 1982|volume = 56|issue = 3|pages = 599–619}}</ref>
==Behavior==
[[File:Endangered Florida manatee (Trichechus manatus) (7636816484).jpg|thumb|Endangered Florida manatee (''Trichechus manatus'')]]
Apart from mothers with their young, or males following a receptive female, manatees are generally solitary animals.<ref name=EoM>{{cite book|editor= Macdonald, D.|author= Best, Robin|year= 1984|title= The Encyclopedia of Mammals|publisher= Facts on File|location= New York|pages= [https://archive.org/details/encyclopediaofma00mals_0/page/292 292–298]|isbn= 0-87196-871-1|url-access= registration|url= https://archive.org/details/encyclopediaofma00mals_0/page/292}}</ref> Manatees spend approximately 50% of the day sleeping submerged, surfacing for air regularly at intervals of less than 20 minutes. The remainder of the time is mostly spent grazing in shallow waters at depths of {{convert|1|-|2|m|ftin|abbr=on}}. The [[Florida]] subspecies (''T. m. latirostris'') has been known to live up to 60 years.
===Locomotion===
Generally, manatees swim at about {{convert|5|to|8|km/h|mph|sigfig=1|abbr=on}}. However, they have been known to swim at up to {{convert|30|km/h|mph|sigfig=1|abbr=on}} in short bursts.<ref>{{Cite web|url=http://www.savethemanatee.org/faqbehavior.htm|title=Manatee FAQ: Behavior|website=www.savethemanatee.org|access-date=2016-09-15|archive-date=2016-09-19|archive-url=https://web.archive.org/web/20160919033414/http://www.savethemanatee.org/faqbehavior.htm|url-status=dead}}</ref>
===Intelligence and learning===
[[File:Manatee attitudes.jpg|thumb|right|Manatee postures in captivity]]
Manatees are capable of understanding discrimination tasks and show signs of complex [[Learning#Associative learning|associative learning]]. They also have good [[long-term memory]].<ref>{{cite journal|last1 = Gerstein|first1 = E. R.|year = 1994|title = The manatee mind: Discrimination training for sensory perception testing of West Indian manatees (''Trichechus manatus'')| journal = Marine Mammals|volume = 1|pages = 10–21}}</ref> They demonstrate discrimination and task-learning abilities similar to [[dolphin]]s and [[pinniped]]s in [[Acoustics|acoustic]] and visual studies.<ref name=GulDie>(Marine Mammal Medicine, 2001, Leslie Dierauf & Frances Gulland, CRC Press)</ref> Social interactions between manatees are highly complex and intricate, which may indicate higher intelligence than previously thought, although they remain poorly understood by science.<ref name="HenautCharlesDelfour2022">{{cite journal |last1=Henaut |first1=Yann |last2=Charles |first2=Aviva |last3=Delfour |first3=Fabienne |date=24 August 2022 |title=Cognition of the manatee: past research and future developments |url=https://link.springer.com/article/10.1007/s10071-022-01676-8 |journal=[[Animal Cognition]] |volume=25 |issue=5 |pages=1049–1058 |doi=10.1007/s10071-022-01676-8 |pmid=36002602 |s2cid=251808935 |access-date=29 October 2022 |archive-date=30 October 2022 |archive-url=https://web.archive.org/web/20221030025414/https://link.springer.com/article/10.1007/s10071-022-01676-8 |url-status=live }}</ref>
===Reproduction===
Manatees typically breed once every two years; generally only a single calf is born. [[Gestation]] lasts about 12 months and to [[weaning|wean]] the calf takes a further 12 to 18 months,<ref name=EoM /> although females may have more than one [[estrous cycle]] per year.<ref name="Ripple">{{cite book|author=Jeff Ripple|title=Manatees and Dugongs of the World|year=1999|url=https://archive.org/details/manateesdugongso0000ripp|url-access=registration|quote=estrous.|publisher=Voyageur Press|isbn=978-1-61060-443-7}}</ref>
===Communication===
Manatees emit a wide range of sounds used in communication, especially between cows and their calves.<ref>{{Cite journal|last1=O'Shea|first1=Thomas J.|last2=Lynn B. Poché|first2=Jr.|date=2006|title=Aspects of Underwater Sound Communication in Florida Manatees (Trichechus manatus latirostris)|journal=Journal of Mammalogy|volume=87|issue=6|pages=1061–1071|doi=10.1644/06-MAMM-A-066R1.1|jstor=4126883|s2cid=42302073|issn=0022-2372|doi-access=free}}</ref> Their ears are large internally but the external openings are small, and they are located four inches behind each eye.<ref>{{cite web|url=https://www.birdsunderwater.com/manatees-hearing/|title=Manatee Ears Cause for Alarm? {{!}} Bird's Underwater|date=2017-08-01|website=Birds Underwater|access-date=2017-10-06|language=en-US|archive-date=2017-10-07|archive-url=https://web.archive.org/web/20171007022420/https://www.birdsunderwater.com/manatees-hearing/|url-status=dead}}</ref> Adults communicate to maintain contact and during sexual and play behaviors. Taste and smell, in addition to sight, sound, and touch, may also be forms of communication.<ref>{{cite web|url=https://seaworld.org/en/animal-info/animal-infobooks/manatee/communication|title=Animal Info Book: Manatee|website=Seaworld Parks & Entertainment|access-date=2016-08-07|archive-date=2017-10-07|archive-url=https://web.archive.org/web/20171007021906/https://seaworld.org/en/animal-info/animal-infobooks/manatee/communication|url-status=dead}}</ref>
===Diet===
Manatees are [[herbivory|herbivores]] and eat over 60 different freshwater (e.g., floating hyacinth, [[Pontederia|pickerel weed]], [[Alternanthera philoxeroides|alligator weed]], [[Pistia|water lettuce]], [[hydrilla]], water celery, [[Chara (alga)|musk grass]], [[mangrove]] leaves) and saltwater plants (e.g., sea grasses, [[Halodule wrightii|shoal grass]], [[Syringodium filiforme|manatee grass]], [[seagrass|turtle grass]], [[Ruppia|widgeon grass]], sea clover, and marine algae).<ref>{{Cite journal|last1=Lefebvre|first1=Lynn W.|last2=Provancha|first2=Jane A.|last3=Slone|first3=Daniel H.|last4=Kenworthy|first4=W. Judson|date=2017|title=Manatee grazing impacts on a mixed species seagrass bed|url=https://www.jstor.org/stable/24898254|journal=Marine Ecology Progress Series|volume=564|pages=29–45|doi=10.3354/meps11986|jstor=24898254|bibcode=2017MEPS..564...29L|issn=0171-8630|access-date=2021-06-16|archive-date=2024-01-27|archive-url=https://web.archive.org/web/20240127183711/https://www.jstor.org/stable/24898254|url-status=live}}</ref><ref>{{Cite journal|last=Domning|first=Daryl P.|date=1981|title=Sea Cows and Sea Grasses|url=https://www.jstor.org/stable/2400692|journal=Paleobiology|volume=7|issue=4|pages=417–420|doi=10.1017/S009483730002546X|jstor=2400692|bibcode=1981Pbio....7..417D|s2cid=88809167|issn=0094-8373|access-date=2021-06-16|archive-date=2024-01-27|archive-url=https://web.archive.org/web/20240127183710/https://www.jstor.org/stable/2400692|url-status=live}}</ref> Using their divided upper lip, an adult manatee will commonly eat up to 10%–15% of their body weight (about 50&nbsp;kg) per day. Consuming such an amount requires the manatee to graze for up to seven hours a day.<ref name="Journey North">{{cite web|url=http://www.learner.org/jnorth/tm/manatee/AdaptationsMouth.html|title=Manatee|publisher=Journey North|year=2003|access-date=April 29, 2014|archive-url=https://web.archive.org/web/20140429180435/http://www.learner.org/jnorth/tm/manatee/AdaptationsMouth.html|archive-date=April 29, 2014|url-status=dead}}</ref> To be able to cope with the high levels of cellulose in their plant based diet, manatees utilize hindgut fermentation to help with the digestion process.<ref>{{Cite book|title=Marine Mammal Physiology|last=Castellini and Mellish|first=Michael and Jo-Ann|publisher=CRC Press|year=2016|isbn=978-1-4822-4267-6|location=Boca Raton, Florida|pages=101}}</ref> Manatees have been known to eat small numbers of fish from nets.<ref name="powell">{{cite journal| last = Powell| first = James| title = Evidence for carnivory in manatee (''Trichechus manatus'')| journal =Journal of Mammalogy| volume = 59| issue = 2|page = 442|year = 1978| doi = 10.2307/1379938| jstor = 1379938}}</ref>
===Feeding behavior===
[[File:Manatee plate.jpg|thumbnail|Manatee plate]]
Manatees use their flippers to "walk" along the bottom whilst they dig for plants and roots in the substrate. When plants are detected, the flippers are used to scoop the vegetation toward the manatee's lips. The manatee has [[Prehensility|prehensile]] lips; the upper lip pad is split into left and right sides which can move independently. The lips use seven muscles to manipulate and tear at plants. Manatees use their lips and front flippers to move the plants into the mouth. The manatee does not have front teeth, however, behind the lips, on the roof of the mouth, there are dense, ridged pads. These horny ridges, and the manatee's lower jaw, tear through ingested plant material.<ref name="Journey North" />
===Dentition===
Manatees have four rows of teeth. There are 6 to 8 high-crowned, open-rooted molars located along each side of the upper and lower jaw giving a total of 24 to 32 flat, rough-textured teeth. Eating gritty vegetation abrades the teeth, particularly the enamel crown; however, research indicates that the enamel structure in manatee molars is weak. To compensate for this, manatee teeth are continually replaced. When anterior molars wear down, they are shed. Posterior molars erupt at the back of the row and slowly move forward to replace these like enamel crowns on a conveyor belt, similarly to [[elephant]]s. This process continues throughout the manatee's lifetime. The rate at which the teeth migrate forward depends on how quickly the anterior teeth abrade. Some studies indicate that the rate is about 1&nbsp;cm/month although other studies indicate 0.1&nbsp;cm/month.<ref name="Journey North" />
==Ecology==
===Range and habitat===
[[File:mapa distribuicao Trichechus.png|right|thumb|Approximate distribution of ''Trichechus''; ''T. manatus'' in green; ''T. inunguis'' in red; ''T. senegalensis'' in orange|alt=Map drawing showing range of three manatee populations]]
[[File:Manatee.jpg|thumb|Three manatees|alt=Underwater photo of three manatees swimming along bottom]]
[[File:Mother manatee and calf.jpg|thumb|Mother manatee and calf]]
Manatees inhabit the shallow, [[marsh]]y coastal areas and rivers of the [[Caribbean Sea]] and the [[Gulf of Mexico]] (''T. manatus'', [[West Indian manatee]]), the [[Amazon basin]] (''T. inunguis'', [[Amazonian manatee]]), and [[West Africa]] (''T. senegalensis'', [[West African manatee]]).<ref>[http://arquivo.pt/wayback/20091014093223/http://www.smithsonianmag.com/science-nature/roosmalen-200802.html ''Trials of a Primatologist.''] – smithsonianmag.com. Accessed March 15, 2008.</ref>
West Indian manatees prefer warmer temperatures and are known to congregate in shallow waters. They frequently migrate through [[brackish water]] [[estuary|estuaries]] to [[freshwater]] [[Spring (hydrosphere)|springs]]. They cannot survive below 15&nbsp;°C (60&nbsp;°F). Their natural source for warmth during winter is warm, spring-fed rivers.
====West Indian====
The coast of the state of [[Georgia (U.S. state)|Georgia]] is usually the northernmost range of the West Indian manatees because their low [[metabolic rate]] does not protect them in cold water. Prolonged exposure to water below 20&nbsp;°C (68&nbsp;°F)&nbsp;can cause "cold stress syndrome" and death.<ref>{{Cite news|first=Rebecca |last=Basu |title=Winter is culprit in manatee death toll |url=http://www.floridatoday.com/article/20100301/NEWS01/3010320/Winter-is-culprit-in-manatee-death-toll |publisher=Florida Today |location=Melbourne, Florida |page=1A |date=1 March 2010 |url-status=dead |archive-url=https://web.archive.org/web/20140222142328/http://www.floridatoday.com/article/20100301/NEWS01/3010320/Winter-is-culprit-in-manatee-death-toll |archive-date=February 22, 2014 }}</ref>
West Indian manatees can move freely between fresh water and salt water. However, studies suggest that they are susceptible to dehydration if freshwater is not available for an extended period of time.<ref>{{cite journal |last1=Ortiz |first1=RM |last2=Worthy |first2=GA |last3=MacKenzie |first3=DS |title=Osmoregulation in wild and captive West Indian manatees (Trichechus manatus). |journal=Physiological Zoology |date=July 1998 |volume=71 |issue=4 |pages=449–57 |doi=10.1086/515427 |pmid=9678505 |hdl=1969.1/182579 |s2cid=40972754 |url=https://faculty.ucmerced.edu/rortiz/pdf/PZ1.pdf |access-date=11 February 2024 |archive-date=15 August 2022 |archive-url=https://web.archive.org/web/20220815034652/http://faculty.ucmerced.edu/rortiz/pdf/PZ1.pdf |url-status=live }}</ref>
Manatees can travel hundreds of miles annually,<ref>{{Cite web |title=Manatee (Trichechus manatus) {{!}} U.S. Fish & Wildlife Service |url=https://www.fws.gov/species/manatee-trichechus-manatus |access-date=2023-09-12 |website=FWS.gov |language=en |archive-date=2023-09-13 |archive-url=https://web.archive.org/web/20230913083541/https://www.fws.gov/species/manatee-trichechus-manatus |url-status=live }}</ref> and have been seen as far north as [[Cape Cod]], and in 1995<ref>{{cite news|url=http://www.deseretnews.com/article/435097/TRAVELIN-MANATEE-FAR-FROM-HOME-AGAIN.html?pg=all|title=TRAVELIN' MANATEE FAR FROM HOME AGAIN|work=Deseret News|date=23 August 1995|access-date=1 January 2016|archive-date=1 January 2016|archive-url=https://web.archive.org/web/20160101134746/http://www.deseretnews.com/article/435097/TRAVELIN-MANATEE-FAR-FROM-HOME-AGAIN.html?pg=all|url-status=dead}}</ref> and again in 2006, one was seen in New York City<ref>{{cite news|url=https://www.nytimes.com/2006/08/07/nyregion/07manatee.html|title=Massive Manatee Is Spotted in Hudson River|date=7 August 2006|access-date=1 January 2016|author=Lee, Jennifer 8|work=[[The New York Times]]|archive-date=9 November 2020|archive-url=https://web.archive.org/web/20201109042741/http://www.nytimes.com/2006/08/07/nyregion/07manatee.html|url-status=live}}</ref> and [[Rhode Island]]'s [[Narragansett Bay]]. A manatee was spotted in the [[Wolf River (Tennessee)|Wolf River]] harbor near the [[Mississippi River]] in downtown Memphis in 2006, and was later found dead {{convert|10|mi|km|order=flip|abbr=on}} downriver in McKellar Lake.<ref>{{cite news|url=https://www.nbcnews.com/id/wbna16160935|title=Manatee found dead in Tenn. lake|agency=Associated Press|date=11 December 2006|access-date=1 January 2016|archive-date=24 September 2016|archive-url=https://web.archive.org/web/20160924124042/http://www.nbcnews.com/id/16160935/ns/us_news-environment/t/manatee-found-dead-tenn-lake/|url-status=live}}</ref> Another manatee was found dead on a New Jersey beach in February 2020, considered especially unusual given the time of year.<ref>{{Cite web|url=https://abc7ny.com/5921110/|title=Dead manatee found along Jersey Shore|date=2020-02-11|website=ABC7 New York|language=en|access-date=2020-02-14|archive-url=https://web.archive.org/web/20200213060149/https://abc7ny.com/5921110/|archive-date=2020-02-13|url-status=dead}}</ref> At the time of the manatee's discovery, the water temperature in the area was below 6.5&nbsp;°C (43.7&nbsp;°F).<ref>{{Cite web|url=http://www.seatemperature.org/north-america/united-states/atlantic-city.htm|title=Atlantic City (NJ) Water Temperature {{!}} United States {{!}} Sea Temperatures|last=Ltd|first=Copyright Global Sea Temperatures-A.-Connect|website=World Sea Temperatures|language=en|access-date=2020-02-14|archive-date=2020-11-27|archive-url=https://web.archive.org/web/20201127092802/https://www.seatemperature.org/north-america/united-states/atlantic-city.htm|url-status=live}}</ref>
The West Indian manatee migrates into Florida rivers—such as the [[Crystal River (Florida)|Crystal]], the [[Homosassa River|Homosassa]], and the [[Chassahowitzka River|Chassahowitzka]] rivers, whose headsprings are 22&nbsp;°C (72&nbsp;°F) all year. Between November and March each year, about 600 West Indian manatees gather in the rivers in [[Citrus County, Florida]] such as the [[Crystal River National Wildlife Refuge]].<ref>{{Cite web|url=https://www.fws.gov/refuge/Crystal_River/about.html|title=About the Refuge|last=US Fish and Wildlife Service|date=November 14, 2017|website=Crystal River National Wildlife Refuge, Florida|access-date=January 28, 2020|archive-date=October 30, 2020|archive-url=https://web.archive.org/web/20201030142613/https://www.fws.gov/refuge/Crystal_River/about.html|url-status=dead}}</ref>
In winter, manatees often gather near the warm-water outflows of power plants along the Florida coast, instead of migrating south as they once did. Some conservationists are concerned that these manatees have become too reliant on these artificially warmed areas.<ref>{{cite news
|url = http://www2.tbo.com/weather/news/2011/jan/07/can-manatees-survive-without-warm-waters-from-powe-ar-16293/
|title =Can manatees survive without warm waters from power plants?
|author = Keith Morelli
|newspaper = The Tampa Tribune
|date = January 7, 2011
|access-date = 2012-05-04}}</ref>
Accurate population estimates of the West Indian manatee in Florida are difficult. They have been called scientifically weak<ref>U.S. Marine Mammal Commission 1999</ref> because they vary widely from year to year, with most areas showing decreases, and little strong evidence of increases except in two areas. Manatee counts are highly variable without an accurate way to estimate numbers. In Florida in 1996, a winter survey found 2,639 manatees; in 1997, a January survey found 2,229, and a February survey found 1,706.<ref name=GulDie/> A statewide synoptic survey in January 2010 found 5,067 manatees living in Florida, the highest number recorded to that time.<ref>{{cite press release|title=Exceptional weather conditions lead to record high manatee count|publisher=Florida Fish and Wildlife Conservation Commission|date=January 20, 2010|url=http://myfwc.com/NEWSROOM/10/statewide/News_10_X_ManateeSynoptic2010.htm|archive-url=https://web.archive.org/web/20110214220230/http://myfwc.com/NEWSROOM/10/statewide/News_10_X_ManateeSynoptic2010.htm|url-status=dead|archive-date=February 14, 2011|access-date=3 February 2017}}</ref>
As of January 2016, the USFWS estimates the range-wide West Indian manatee population to be at least 13,000; as of January 2018, at least 6,100 are estimated to be in Florida.<ref name="fws.gov">{{cite press release |last1=Service |first1=U. S. Fish and Wildlife |title=U.S. Fish and Wildlife Service to Reclassify West Indian Manatee from Endangered to Threatened |url=https://www.fws.gov/news/ShowNews.cfm?_ID=35428 |website=www.fws.gov |language=en |access-date=2021-03-25 |archive-date=2021-05-08 |archive-url=https://web.archive.org/web/20210508103004/https://www.fws.gov/news/ShowNews.cfm?_ID=35428 |url-status=live }}</ref><ref>{{cite web |url=http://myfwc.com/research/manatee/research/population-monitoring/synoptic-surveys/ |title=Manatee Synoptic Surveys |publisher=Florida Fish and Wildlife Conservation Commission |date=2018 |access-date=21 July 2018 |archive-date=6 September 2015 |archive-url=https://web.archive.org/web/20150906135944/http://myfwc.com/research/manatee/research/population-monitoring/synoptic-surveys/ |url-status=dead }}</ref>
[[Population viability analysis|Population viability]] studies conducted in 1997 found that decreasing adult survival and eventual extinction were probable future outcomes for Florida manatees unless they received more protection.<ref>(Marmontel, Humphrey, O'Shea 1997, "Population Variability Analysis of the Florida Manatee, 1976–1992", ''Conserv. biol''., 11: 467–481)</ref> The U.S. Fish and Wildlife Service proposed downgrading the manatee's status from endangered to threatened in January 2016 after more than 40 years.<ref>{{cite web| url=http://news.discovery.com/animals/record-6250-manatees-spotted-in-florida-waters-160226.htm| title=Record 6,250 Manatees Spotted in Florida Waters| date=February 26, 2016| publisher=Discovery| access-date=February 26, 2016| archive-date=February 28, 2016| archive-url=https://web.archive.org/web/20160228001022/http://news.discovery.com/animals/record-6250-manatees-spotted-in-florida-waters-160226.htm| url-status=dead}}</ref>
There is a small population of the subspecies [[West Indian manatee|Antillean manatee]] (''T. m. manatus'') found in Mexico's Caribbean coastal area. The best estimate for this population is 200-250.<ref>{{Cite journal |last1=Robles Herrejón |first1=Juan Carlos |last2=Morales-Vela |first2=Benjamín |last3=Ortega-Argueta |first3=Alejandro |last4=Pozo |first4=Carmen |last5=Olivera-Gómez |first5=León David |date=June 2020 |title=Management effectiveness in marine protected areas for conservation of Antillean manatees on the eastern coast of the Yucatan Peninsula, Mexico |url=https://onlinelibrary.wiley.com/doi/10.1002/aqc.3323 |journal=Aquatic Conservation: Marine and Freshwater Ecosystems |language=en |volume=30 |issue=6 |pages=1182–1193 |doi=10.1002/aqc.3323 |bibcode=2020ACMFE..30.1182R |issn=1052-7613 |access-date=2024-03-05 |archive-date=2022-11-21 |archive-url=https://web.archive.org/web/20221121174902/https://onlinelibrary.wiley.com/doi/10.1002/aqc.3323 |url-status=live }}</ref> As of 2022, a new manatee habitat was discovered by [[Klaus Thymann]] within the cenotes of [[Sian Kaʼan Biosphere Reserve|Sian Ka'an Biosphere Reserve]] on the [[Yucatán Peninsula]]. The explorer and his team documented the discovery with a 12-minute film that is available on the interactive streaming platform WaterBear.<ref>{{Cite web |title=WaterBear |url=https://www.waterbear.com/ |access-date=2024-03-05 |website=www.waterbear.com |language=en}}</ref> The discovery got picked up by the [[New Scientist]] in 2024, who featured in a 10-minute short film.<ref>{{Cite web |last=Stock |first=David |title=Manatees discovered in pristine but threatened underwater cave habitat |url=https://www.newscientist.com/video/2413243-manatees-discovered-in-pristine-but-threatened-underwater-cave-habitat/ |access-date=2024-03-05 |website=New Scientist |language=en-US |archive-date=2024-02-26 |archive-url=https://web.archive.org/web/20240226060553/https://www.newscientist.com/video/2413243-manatees-discovered-in-pristine-but-threatened-underwater-cave-habitat/ |url-status=live }}</ref>
====Amazonian====
The freshwater Amazonian manatee (''T. inunguis'') inhabits the Central Amazon Basin in [[Brazil]], eastern [[Peru|Perú]], southeastern [[Colombia]], but not [[Ecuador]]. It is the only exclusively freshwater manatee, and is also the smallest. Since they are unable to reduce peripheral heat loss, it is found primarily in tropical waters.<ref>{{Cite web|title=Amazonian Manatee - Facts, Information & Habitat|url=https://animalcorner.org/animals/amazonian-manatee/|access-date=2021-12-24|language=en-US|archive-date=2021-12-24|archive-url=https://web.archive.org/web/20211224060223/https://animalcorner.org/animals/amazonian-manatee/|url-status=live}}</ref>
====West African====
They are found in coastal marine and estuarine habitats, and in freshwater river systems along the west coast of Africa from the [[Senegal River]] south to the [[Cuanza River]] in [[Angola]]. They live as far upriver on the [[Niger River]] as [[Koulikoro]] in [[Mali]], {{convert|2000|km|abbr=on}} from the coast.<ref name=iucnWA>{{cite iucn | author = Keith Diagne, L. | title = '' Trichechus senegalensis'' | volume = 2016 | page = e.T22104A97168578 | year = 2016 }}{{Dead link|date=August 2019 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>
===Predation===
In relation to the threat posed by humans, [[predation]] does not present a significant threat to manatees.<ref name=":0" /> When threatened, the manatee's response is to dive as deeply as it can, suggesting that threats have most frequently come from land dwellers such as humans rather than from other water-dwelling creatures such as [[Caiman|caimans]] or sharks.<ref name=":0" />
==Relation to humans==
{{Main|Manatee conservation}}
===Threats===
[[File:Manatee - Blue Spring State Park.JPG|thumb|alt=Photo of manatee next to kayak|Young manatees can be curious; this individual is inspecting a [[kayak]].]]
The main causes of death for manatees are human-related issues, such as habitat destruction and human objects. Natural causes of death include adverse temperatures, predation by crocodiles on young, and disease.<ref name="auto1">{{cite journal|last1=Luiselli|first1=L.|last2=Akani|first2=G.C.|last3=Ebere|first3=N.|last4=Angelici|first4=F. M.|last5=Amori|first5=G.|last6=Politano|first6=E.|date=2012|title=Macro-habitat preferences by the African manatee and crocodiles – ecological and conservation implications|journal=Web Ecology|volume=12|issue=1|pages=39–48|doi=10.5194/we-12-39-2012|doi-access=free}}</ref>
====Ship strikes====
Their slow-moving, curious nature, coupled with dense coastal development, has led to many violent collisions with propeller-driven boats and ships, leading frequently to maiming, disfigurement, and even death. As a result, a large proportion of manatees exhibit spiral cutting propeller scars on their backs, usually caused by larger vessels that do not have [[skeg]]s in front of the propellers like the smaller outboard and inboard-outboard recreational boats have. They are now even identified by humans based on their scar patterns. Many manatees have been cut in two by large vessels like ships and tug boats, even in the highly populated lower St. Johns River's narrow channels. Some are concerned that the current situation is inhumane, with upwards of 50 scars and disfigurements from vessel strikes on a single manatee.<ref>[https://web.archive.org/web/20081007102448/http://www.cdnn.info/news/eco/e060111.html Florida boaters killing endangered manatees]. Cyber Diver News Network. 11 January 2006</ref> Often, the lacerations lead to infections, which can prove fatal. Internal injuries stemming from being trapped between hulls and docks and impacts have also been fatal. Recent testing{{citation needed|date=November 2014}} shows that manatees may be able to hear speed boats and other watercraft approaching, due to the frequency the boat makes. However, a manatee may not be able to hear the approaching boats when they are performing day-to-day activities or distractions. The manatee has a tested frequency range of 8 to 32 kilohertz.<ref>{{Cite journal|url = https://journals.biologists.com/jeb/article/215/9/1442/11311/Audiogram-and-auditory-critical-ratios-of-two|doi = 10.1242/jeb.065649|title = Audiogram and auditory critical ratios of two Florida manatees (Trichechus manatus latirostris)|year = 2012|last1 = Gaspard|first1 = Joseph C.|last2 = Bauer|first2 = Gordon B.|last3 = Reep|first3 = Roger L.|last4 = Dziuk|first4 = Kimberly|last5 = Cardwell|first5 = Adrienne|last6 = Read|first6 = Latoshia|last7 = Mann|first7 = David A.|journal = Journal of Experimental Biology|volume = 215|issue = 9|pages = 1442–1447|pmid = 22496279|s2cid = 11725126|doi-access = free|access-date = 2021-12-24|archive-date = 2021-12-24|archive-url = https://web.archive.org/web/20211224150105/https://journals.biologists.com/jeb/article/215/9/1442/11311/Audiogram-and-auditory-critical-ratios-of-two|url-status = live}}</ref>
Manatees hear on a higher frequency than would be expected for such large marine mammals. Many large boats emit very low frequencies, which confuse the manatee and explain their lack of awareness around boats. The [[Lloyd's mirror#Underwater acoustics|Lloyd's mirror]] effect results in low frequency propeller sounds not being discernible near the surface, where most accidents occur. Research indicates that when a boat has a higher frequency the manatees rapidly swim away from danger.<ref>[http://www.scienceagogo.com/news/19990629210228data_trunc_sys.shtml Manatees hard of hearing] {{Webarchive|url=https://web.archive.org/web/20110928150106/http://www.scienceagogo.com/news/19990629210228data_trunc_sys.shtml |date=2011-09-28 }}. Scienceagogo.com (1999-07-30). Retrieved on 2011-12-03.</ref>
In 2003, a population model was released by the [[United States Geological Survey]] that predicted an extremely grave situation confronting the manatee in both the Southwest and Atlantic regions where the vast majority of manatees are found. It states,
{{blockquote|In the absence of any new management action, that is, if boat mortality rates continue to increase at the rates observed since 1992, the situation in the Atlantic and Southwest regions is dire, with no chance of meeting recovery criteria within 100 years.<ref>[http://www.savethemanatee.org/newsprpopulationmodel.htm Long Term Prospects for Manatee Recovery Look Grim, According To New Data Released By Federal Government] {{Webarchive|url=https://web.archive.org/web/20070712180614/http://www.savethemanatee.org/newsprpopulationmodel.htm |date=2007-07-12 }}. Savethemanatee.org (2003-04-29). Retrieved on 2011-12-03.</ref> "Hurricanes, cold stress, red tide poisoning and a variety of other maladies threaten manatees, but by far their greatest danger is from watercraft strikes, which account for about a quarter of Florida manatee deaths," said study curator John Jett.<ref name=uf>[http://news.ufl.edu/2007/07/03/manatee-3/ ufl.edu] {{webarchive|url=https://web.archive.org/web/20100612180925/http://news.ufl.edu/2007/07/03/manatee-3/ |date=2010-06-12 }}. News.ufl.edu (2007-07-03). Retrieved on 2011-12-03.</ref>|author=|title=|source=}}
[[File:Manatee bearing scars on back from boat propeller.jpg|thumb|Manatee bearing scars on its back from a boat propeller.]]
According to marine mammal [[veterinarian]]s:
{{Blockquote|The severity of mutilations for some of these individuals can be astounding – including long term survivors with completely severed tails, major tail mutilations, and multiple disfiguring dorsal lacerations. These injuries not only cause gruesome wounds, but may also impact population processes by reducing calf production (and survival) in wounded females – observations also speak to the likely pain and suffering endured.<ref name=GulDie/> In an example, they cited one case study of a small calf "with a severe dorsal mutilation trailing a decomposing piece of dermis and muscle as it continued to accompany and nurse from its mother&nbsp;... by age 2 its dorsum was grossly deformed and included a large protruding rib fragment visible."<ref name=GulDie/>}}
These veterinarians go on to state:
{{blockquote|[T]he overwhelming documentation of gruesome wounding of manatees leaves no room for denial. Minimization of this injury is ''explicit'' in the Recovery Plan, several state statutes, and federal laws, and ''implicit'' in our society's ethical and moral standards.<ref name=GulDie/>}}
One quarter of annual manatee deaths in Florida are caused by boat collisions with manatees.<ref>{{Cite journal|title = Conserving Manatees: Knowledge, Attitudes, and Intentions of Boaters in Tampa Bay, Florida|url = https://conbio.onlinelibrary.wiley.com/doi/abs/10.1046/j.1523-1739.2003.01452.x|journal = Conservation Biology|year = 2003|doi = 10.1046/j.1523-1739.2003.01452.x|last1 = Aipanjiguly|first1 = Sampreethi|last2 = Jacobson|first2 = Susan K.|last3 = Flamm|first3 = Richard|volume = 17|issue = 4|pages = 1098–1105| bibcode=2003ConBi..17.1098A |s2cid = 86770081|access-date = 2021-11-26|archive-date = 2021-11-26|archive-url = https://web.archive.org/web/20211126224246/https://conbio.onlinelibrary.wiley.com/doi/abs/10.1046/j.1523-1739.2003.01452.x|url-status = dead}}</ref> In 2009, of the 429 Florida manatees recorded dead, 97 were killed by commercial and recreational vessels, which broke the earlier record number of 95 set in 2002.<ref>{{cite web|url=http://myfwc.com/research/manatee/rescue-mortality-response/mortality-statistics/|title=Manatee Mortality Statistics|publisher=Fish and Wildlife Research Institute|access-date=1 December 2010|archive-date=1 April 2011|archive-url=https://web.archive.org/web/20110401085515/http://myfwc.com/research/manatee/rescue-mortality-response/mortality-statistics|url-status=dead}}</ref><ref>{{cite web
|title        = Manatee Deaths From Boat Strikes Approach Record: Club Asks For Boaters' Urgent Help
|publisher    = Save the Manatee Club
|access-date   = 1 May 2010
|url          = http://www.savethemanatee.org/news_oped_mortality_12-09.html
|archive-url  = https://web.archive.org/web/20110208183450/http://savethemanatee.org/news_oped_mortality_12-09.html
|archive-date = 2011-02-08
|url-status     = dead
}}</ref>
====Red tide====
Another cause of manatee deaths are [[red tide]]s, a term used for the proliferation, or "blooms", of the microscopic marine algae ''[[Karenia brevis]]''. This [[dinoflagellate]] produces [[brevetoxin]]s that can have toxic effects on the [[central nervous system]] of animals.<ref>{{cite journal
|title = Brevetoxicosis: Red tides and marine mammal mortalities
|journal = Nature|issue = 7043| pages = 755–756
|date = 9 June 2005
|doi=10.1038/nature435755a
|pmid = 15944690
|last1 = Flewelling
|first1 = LJ
|last2 = Naar
|first2 = JP
|last3 = Abbott
|first3 = JP
|last4 = Baden
|first4 = DG
|last5 = Barros
|first5 = NB
|last6 = Bossart
|first6 = GD
|last7 = Bottein
|first7 = MY
|last8 = Hammond
|first8 = DG
|last9 = Haubold
|first9 = EM
| display-authors = 8
|volume = 435
|pmc = 2659475
|bibcode = 2005Natur.435..755F}}</ref>
In 1996, a red tide was responsible for 151 manatee deaths in Florida.<ref>{{cite news
| url = https://www.reuters.com/article/us-usa-florida-manatees-idUSBRE9BJ1BQ20131220
| title = Manatee death toll hits record in Florida, 'Red Tide' blamed
| work = Reuters
| access-date = 1 February 2016
| archive-date = 24 September 2018
| archive-url = https://web.archive.org/web/20180924113313/https://www.reuters.com/article/us-usa-florida-manatees-idUSBRE9BJ1BQ20131220
| url-status = live
}}</ref> The bloom was present from early March to the end of April and killed approximately 15% of the known population of manatees along South Florida's western coast.<ref>{{cite news
|title = Scientists Say Toxin in Red Tide Killed Scores of Manatees
|newspaper = New York Times
|date = July 5, 1996
|access-date = 1 May 2010
|url = https://www.nytimes.com/1996/07/05/us/scientists-say-toxin-in-red-tide-killed-scores-of-manatees.html?pagewanted=1
|archive-date = 11 May 2013
|archive-url = https://web.archive.org/web/20130511152402/http://www.nytimes.com/1996/07/05/us/scientists-say-toxin-in-red-tide-killed-scores-of-manatees.html?pagewanted=1
|url-status = live
}}</ref> Other blooms in 1982 and 2005 resulted in 37 and 44 deaths respectively,<ref>{{cite news
|title = Mystery epidemic killing manatees
|page = 38
|publisher = Local & State
|date = April 9, 1996
|access-date = 1 May 2010
|url = https://news.google.com/newspapers?nid=1356&dat=19960409&id=0B8VAAAAIBAJ&sjid=dgcEAAAAIBAJ&pg=5443,3325057
|archive-date = 27 August 2021
|archive-url = https://web.archive.org/web/20210827152057/https://news.google.com/newspapers?nid=1356&dat=19960409&id=0B8VAAAAIBAJ&sjid=dgcEAAAAIBAJ&pg=5443%2C3325057
|url-status = live
}}</ref> and a red tide killed 123 manatees between November 2022 and June 2023.<ref>{{Cite web |title=2023 Bloom |url=https://myfwc.com/research/manatee/rescue-mortality-response/statistics/mortality/2023-bloom/ |access-date=2024-04-09 |website=Florida Fish And Wildlife Conservation Commission |language=en |archive-date=2024-04-04 |archive-url=https://web.archive.org/web/20240404153407/https://myfwc.com/research/manatee/rescue-mortality-response/statistics/mortality/2023-bloom/ |url-status=live }}</ref>
====Starvation====
In 2021 a massive die-off of [[seagrass]] along the [[Atlantic Ocean|Atlantic]] coast of [[Florida]] left manatees without enough food to eat. As a result of this [[ecological disaster]] Florida's manatees began dying at an alarming rate, largely from [[starvation]].<ref>{{cite web |title=Manatees are starving in Florida. Wildlife agencies are scrambling to save them |date=2 Dec 2021 |accessdate=24 Feb 2022 |author=Greg Allen |website=NPR |url=https://www.npr.org/2021/12/02/1060439776/manatees-starving-seagrass-dying-florida |archive-date=24 February 2022 |archive-url=https://web.archive.org/web/20220224130511/https://www.npr.org/2021/12/02/1060439776/manatees-starving-seagrass-dying-florida |url-status=live }}</ref> In early 2022 the [[U.S. Fish and Wildlife Service]] began a feeding program to address the situation by distributing 3,000 pounds (1,361&nbsp;kg) of [[lettuce]] per day to save the malnourished animals.<ref>{{cite web |title=Florida wildlife officials are distributing 3,000 pounds of lettuce a day to save starving manatees |date=17 Feb 2022 |author=Amanda Jackson |website=CNN |url=https://www.cnn.com/2022/02/16/us/florida-starving-manatee-feeding-program-trnd-scn/?hpt=ob_blogfooterold |access-date=24 February 2022 |archive-date=24 February 2022 |archive-url=https://web.archive.org/web/20220224183926/https://www.cnn.com/2022/02/16/us/florida-starving-manatee-feeding-program-trnd-scn/?hpt=ob_blogfooterold |url-status=live }}</ref>
====Additional threats====
Manatees can also be crushed and isolated in water control structures ([[Navigation lock|navigation locks]], [[floodgate]]s, etc.) and are occasionally killed by entanglement in fishing gear, such as [[crab pot]] float lines, box traps, and shark nets.<ref name=iucnWA/>
While humans are allowed to swim with manatees in one area of Florida,<ref>[http://www.savethemanatee.org/ta_harassment.htm Help End Manatee Harassment in Citrus County, Florida!] {{Webarchive|url=https://web.archive.org/web/20070430191437/http://www.savethemanatee.org/ta_harassment.htm |date=2007-04-30 }}. Savethemanatee.org. Retrieved on 2011-12-03.</ref> there have been numerous charges of people harassing and disturbing the manatees.<ref>[http://www.sptimes.com/2007/02/11/Citrus/Manatee_abuse_caught_.shtml St. Petersburg Times – Manatee Abuse Caught on Tape] {{Webarchive|url=https://web.archive.org/web/20090601161308/http://www.sptimes.com/2007/02/11/Citrus/Manatee_abuse_caught_.shtml |date=2009-06-01 }}. Sptimes.com. Retrieved on 2011-12-03.</ref> According to the United States Fish and Wildlife Service, approximately 99 manatee deaths each year are related to human activities.<ref>{{Cite web
| url = http://www.chicagotribune.com/news/nationworld/ct-monarch-butterflies-manatees-populations-20160229-story.html
| title = Monarch butterfly, manatee populations are on a big rebound
| last = Tribune
| first = Chicago
| website = chicagotribune.com
| date = 29 February 2016
| access-date = 2016-03-01
}}</ref> In January 2016, there were 43 manatee deaths in Florida alone.<ref>{{Cite web
| url = http://myfwc.com/media/3401133/January.pdf
| title = January 2016 Preliminary Manatee Mortality Table by County
| date = January 2016
| access-date = February 20, 2016
| archive-date = March 6, 2016
| archive-url = https://web.archive.org/web/20160306043012/http://myfwc.com/media/3401133/January.pdf
| url-status = dead
}}</ref>
===Conservation===
All three species of manatee are listed by the [[International Union for Conservation of Nature|World Conservation Union]] as vulnerable to extinction. However, The [[United States Fish and Wildlife Service|U.S. Fish and Wildlife Service (FWS)]] does not consider the West Indian manatee to be "endangered" anymore, having downgraded its status to "threatened" as of March 2017. They cite improvements to habitat conditions, population growth and reductions of threats as reasoning for the change. The reclassification was met with controversy, with Florida congressman [[Vern Buchanan]] and groups such as the Save the Manatee Club and the [[Center for Biological Diversity]] expressing concerns that the change would have a detrimental effect on conservation efforts.<ref>{{cite news |last1=Wang |first1=Amy B. |title=Manatees are no longer listed as endangered. Should we celebrate or fret? |url=https://www.washingtonpost.com/news/animalia/wp/2017/03/31/manatees-are-no-longer-listed-as-endangered-should-we-celebrate-or-fret/ |date=March 31, 2017 |newspaper=[[The Washington Post]] |access-date=April 7, 2020 |archive-date=April 7, 2020 |archive-url=https://web.archive.org/web/20200407031900/https://www.washingtonpost.com/news/animalia/wp/2017/03/31/manatees-are-no-longer-listed-as-endangered-should-we-celebrate-or-fret/ |url-status=live }}</ref> The new classification will not affect current federal protections.<ref name="fws.gov" /> West Indian manatees were originally classified as endangered with the 1967 class of endangered species.<ref>{{Cite web|url=https://www.fws.gov/endangered/class-of-1967/index.html|title=Endangered Species {{!}} Class of 1967|website=www.fws.gov|access-date=2020-01-30|archive-date=2020-05-24|archive-url=https://web.archive.org/web/20200524172900/https://www.fws.gov/endangered/class-of-1967/index.html|url-status=dead}}</ref>
Manatee deaths in the state of Florida nearly doubled in 2021 from 637 (2020) to 1100.<ref>{{Cite web |title=FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION MARINE MAMMAL PATHOBIOLOGY LABORATORY Preliminary 2022 Manatee Mortality Table by County |url=https://myfwc.com/media/28361/preliminary.pdf |access-date=2023-03-24 |archive-date=2023-03-24 |archive-url=https://web.archive.org/web/20230324235638/https://myfwc.com/media/28361/preliminary.pdf |url-status=live }}</ref> Although this number decreased to 800 in 2022, it is likely that current rate of development in Florida, climate change, and decreasing water quality, habitat range, and genetic diversity among this population may lead to reconsideration of the West Indian Manatee as an endangered species.<ref>{{Cite web |last=Jones Jr. |first=Robert C. |date=February 2, 2022 |title=NO LONGER ENDANGERED, MANATEES NOW FACE ANOTHER CRISIS |url=https://news.miami.edu/stories/2022/02/no-longer-endangered,-manatees-now-face-another-crisis.html |access-date=March 24, 2023 |archive-date=March 24, 2023 |archive-url=https://web.archive.org/web/20230324235643/https://news.miami.edu/stories/2022/02/no-longer-endangered,-manatees-now-face-another-crisis.html |url-status=live }}</ref> Manatee population in the United States reached a low in the 1970s, during which only a few hundred individuals lived in the nation.<ref>{{cite web |title=Manatee reclassified from endangered to threatened as habitat improves and population expands - existing federal protections remain in place |url=https://www.fws.gov/southeast/news/2017/03/manatee-reclassified-from-endangered-to-threatened-as-habitat-improves-and-population-expands-existing-federal-protections-remain-in-place/ |website=Southeast Region of the U.S. Fish and Wildlife Service |access-date=2020-04-07 |archive-date=2020-05-29 |archive-url=https://web.archive.org/web/20200529193212/https://www.fws.gov/southeast/news/2017/03/manatee-reclassified-from-endangered-to-threatened-as-habitat-improves-and-population-expands-existing-federal-protections-remain-in-place/ |url-status=dead }}</ref> As of February 2016, 6,250 manatees were reported swimming in Florida's springs.<ref>{{Cite web|url=http://home.tampabay.com/news/environment/wildlife/record-breaking-number-of-manatees-counted-during-annual-winter-survey/2266821|title=Record-breaking number of manatees counted during annual winter survey|website=Tampa Bay Times|url-status=dead|archive-url=https://web.archive.org/web/20160305181336/http://home.tampabay.com/news/environment/wildlife/record-breaking-number-of-manatees-counted-during-annual-winter-survey/2266821|archive-date=2016-03-05|access-date=2016-03-01}}</ref> It is illegal under federal and Florida law to injure or harm a manatee.
There are many conservation programs that have been created to help manatees. [[Save the Manatee Club]] is a non-profit group and membership organization that works to protect manatees and their aquatic ecosystems.  Founded by [[Bob Graham]], former Florida governor, and singer/songwriter [[Jimmy Buffett]], this is today's leading manatee conservation club.<ref>{{Cite web|title=Save The Manatees|url=https://www.savethemanatee.org/|website=Save The Manatees|access-date=2021-11-23|archive-date=2021-11-23|archive-url=https://web.archive.org/web/20211123234552/https://www.savethemanatee.org/|url-status=live}}</ref>{{self-published inline|date=March 2022}}
The [[MV Freedom Star|MV ''Freedom Star'']] and [[MV Liberty Star|MV ''Liberty Star'']], ships used by [[NASA]] to tow [[Space Shuttle Solid Rocket Booster]]s back to [[Kennedy Space Center]], were propelled only by water jets to protect the endangered manatee population that inhabits regions of the [[Banana River]] where the ships are based.
Brazil outlawed hunting in 1973 in an effort to preserve the species. Deaths by boat strikes are still common.<ref name="auto">{{Cite web|last=Fairclough|first=Caty|title=From Mermaids to Manatees: the Myth and the Reality {{!}} Smithsonian Ocean|url=http://ocean.si.edu/ocean-life/marine-mammals/mermaids-manatees-myth-and-reality|access-date=2021-12-24|website=ocean.si.edu|language=en}}</ref><ref>{{Cite web|title=New Study Shows Impact of Watercraft on Manatees|url=https://myfwc.com/research/manatee/rescue-mortality-response/publication/|access-date=2021-12-24|website=Florida Fish And Wildlife Conservation Commission|language=en|archive-date=2021-12-24|archive-url=https://web.archive.org/web/20211224060223/https://myfwc.com/research/manatee/rescue-mortality-response/publication/|url-status=live}}</ref> Although countries are protecting Amazonian manatees in the locations where they are endangered, as of 1994 there were no enforced laws, and the manatees were still being captured throughout their range.<ref>{{cite journal |last1= Weber Rosas |first1= F.C. |date= June 1994 |title= Biology, conservation, and status of the Amazonian Manatee ''Trichechus inunguis'' |journal= Mammal Review |volume= 24 |issue= 2 |pages= 49–59 |doi= 10.1111/j.1365-2907.1994.tb00134.x}}</ref>
===Captivity===
[[File:Manatee at Sea World Orlando Mar 10.JPG|thumb|A manatee at SeaWorld, Florida|alt=Underwater photo of manatee]]
There are a number of manatee rehabilitation centers in the United States. These include three government-run critical care facilities in Florida at [[Lowry Park Zoo]], [[Miami Seaquarium]], and [[SeaWorld Orlando]]. After initial treatment at these facilities, the manatees are transferred to rehabilitation facilities before release. These include the [[Cincinnati Zoo and Botanical Garden]], [[Columbus Zoo and Aquarium]], [[Epcot]]'s The Seas, [[South Florida Museum]], and [[Homosassa Springs Wildlife State Park]].<ref>{{cite web | url=https://www.fws.gov/northflorida/Manatee/Rescue-Rehab/manatee-rescue-rehab.htm | title=Manatee Rescue, Rehabilitation and Release Program | access-date=2016-12-31 | archive-date=2017-01-01 | archive-url=https://web.archive.org/web/20170101161314/https://www.fws.gov/northflorida/Manatee/Rescue-Rehab/manatee-rescue-rehab.htm | url-status=dead }}</ref>
The Columbus Zoo was a founding member of the Manatee Rehabilitation Partnership in 2001. Since 1999, the zoo's Manatee Bay facility has helped rehabilitate 20 manatees.<ref>{{cite web | url=https://globalimpact.columbuszoo.org/projects/project/manatee-rehab-in-the-united-states | title=Global Impact - Project | access-date=2016-12-31 | archive-date=2015-09-05 | archive-url=https://web.archive.org/web/20150905202334/https://globalimpact.columbuszoo.org/projects/project/manatee-rehab-in-the-united-states | url-status=dead }}</ref> The Cincinnati Zoo has rehabilitated and released more than a dozen manatees since 1999.<ref>{{cite web | url=http://cincinnatizoo.org/rescue-rehabilitation-and-release-of-florida-manatees/ | title=Rescue, Rehabilitation and Release of Florida Manatees | access-date=2016-12-31 | archive-date=2017-01-01 | archive-url=https://web.archive.org/web/20170101093235/http://cincinnatizoo.org/rescue-rehabilitation-and-release-of-florida-manatees/ | url-status=live }}</ref>
Manatees can also be viewed in a number of European zoos, such as the [[Tierpark Berlin]] and the [[Nuremberg Zoo]] in Germany, in [[ZooParc de Beauval]] in France, the [[Aquarium of Genoa]] in Italy and the [[Royal Burgers' Zoo]] in Arnhem, the Netherlands, where manatees have parented offspring.<ref>{{cite news|title= Adventure in the mangrove forest|url= https://www.burgerszoo.com/eco-display/mangrove|access-date= 2021-06-11|archive-date= 2021-06-11|archive-url= https://web.archive.org/web/20210611145658/https://www.burgerszoo.com/eco-display/mangrove|url-status= live}}</ref> The [[River Safari]] at [[Singapore]] features seven of them.<ref>{{cite news |url= http://www.straitstimes.com/breaking-news/singapore/story/manatees-move-worlds-largest-freshwater-aquarium-river-safari-20130313 |title= Manatees move into world's largest freshwater aquarium at River Safari |newspaper= The Straits Times |date= 13 March 2013 |access-date= 2013-07-24 |last1= Tan |first1= Sue-Ann |archive-date= 2013-05-19 |archive-url= https://web.archive.org/web/20130519124453/http://www.straitstimes.com/breaking-news/singapore/story/manatees-move-worlds-largest-freshwater-aquarium-river-safari-20130313 |url-status= live }}</ref>
The oldest manatee in captivity was [[Snooty]],<ref>{{cite web|last1=Aronson|first1=Claire|title=Guinness World Records names Snooty of Bradenton as 'Oldest Manatee in Captivity'|url=http://www.bradenton.com/2015/06/26/5867910/guinness-world-records-names-snooty.html|website=bradenton.com|publisher=Bradenton Herald|access-date=26 June 2015|archive-url=https://web.archive.org/web/20150628231038/http://www.bradenton.com/2015/06/26/5867910/guinness-world-records-names-snooty.html|archive-date=28 June 2015|url-status=dead}}</ref> at the [[South Florida Museum]]'s Parker Manatee Aquarium in [[Bradenton, Florida]]. Born at the Miami Aquarium and Tackle Company on July 21, 1948, Snooty was one of the first recorded captive manatee births. Raised entirely in captivity, Snooty was never to be released into the wild. As such he was the only manatee at the aquarium, and one of only a few captive manatees in the United States that was allowed to interact with human handlers. That made him uniquely suitable for manatee research and education.<ref>{{cite book |author=<!--Staff writer(s); no by-line.--> |title= Snooty the Manatee|publisher= South Florida Museum |isbn= 978-1-56944-441-2}}</ref>
Snooty died suddenly two days after his 69th birthday, July 23, 2017, when he was found in an underwater area only used to access plumbing for the exhibit life support system. The South Florida Museum's initial press release stated, “Early indications are that an access panel door that is normally bolted shut had somehow been knocked loose and that Snooty was able to swim in.”<ref>{{cite web | url = http://www.southfloridamuseum.org/south-florida-museum-mourns-death-snooty-worlds-oldest-manatee/ | title = Oldest living manatee in captivity dies a day after celebrating 69th birthday | date = 23 July 2017 | access-date = 2017-07-23 | archive-date = 2017-07-23 | archive-url = https://web.archive.org/web/20170723200142/http://www.southfloridamuseum.org/south-florida-museum-mourns-death-snooty-worlds-oldest-manatee/ | url-status = live }}</ref>
==== Guyana ====
Since the 19th century, [[Georgetown, Guyana]] has kept [[West Indian manatee]]s in [[Guyana Botanical Gardens|its botanical garden]], and later, [[Guyana National Park|its national park]].<ref>{{cite news |title=Abary Creek manatees under threat |url=https://www.stabroeknews.com/2008/09/30/news/guyana/abary-creek-manatees-under-threat/ |work=Stabroek News |date=30 September 2008 |quote=there are 23 manatees [...] between the Botanical Gardens and the National Park. They have been there for more than 129 years, and reports are that they came from the [[Abary Creek]]. |access-date=16 June 2020 }}{{dead link|date=July 2021|bot=medic}}{{cbignore|bot=medic}}</ref>
In the 1910s and again in the 1950s, [[sugar estate]]s in Guyana used manatees to keep their irrigation canals weed-free.<ref>{{cite book|author=National Science Research Council (Guyana).|title=An International Centre for Manatee Research|url=https://books.google.com/books?id=qz4rAAAAYAAJ&pg=PA13|year=1974|publisher=National Academies|location=Georgetown, Guyana|page=13}}</ref>
Between the 1950s and 1970s, the Georgetown [[water treatment plant]] used manatees in their storage canals for the same purpose.<ref>{{cite book|author=National Research Council|title=Making Aquatic Weeds Useful|url=https://books.google.com/books?id=pG-8h6JufaEC&pg=PA35|year=2002|publisher=The Minerva Group|isbn=978-0-89499-180-6|page=35|quote= In the Georgetown Water and Sewerage Works, two manatees [...] were introduced in 1952 to a canal [...] In the 24 years since then, manatees have been used to keep this water (the city's municipal supply) weed-free.}}</ref>
===Culture===
[[File:Milwaukee Public Museum November 2022 101 (Manatee at Blue Springs, Florida).jpg|thumb|left|The ''Manatee at Blue Springs, Florida'' diorama at the [[Milwaukee Public Museum]]]]
The manatee has been linked to folklore on [[mermaid]]s.<ref name="auto"/> In [[West Africa]]n folklore, they were considered sacred and thought to have been once human. Killing one was [[taboo]] and required penance.<ref name = "Cooper92">{{cite book |last=Cooper |first=JC |title=Symbolic and Mythological Animals |page=157 |year=1992 |publisher= Aquarian Press |location=London |isbn=1-85538-118-4}}</ref>
In the novel ''[[Moby-Dick]]'', [[Herman Melville]] distinguishes manatees ("Lamatins", cf. ''[[wikt:lamantin|lama{{strong|n}}tins]]'') from small whales; stating, "I am aware that down to the present time, the fish styled Lamatins and [[Dugong]]s (Pig-fish and Sow-fish of the [[Coffin (whaling family)|Coffins of Nantucket)]] are included by many naturalists among the whales. But as these pig-fish are a noisy, contemptible set, mostly lurking in the mouths of rivers, and feeding on wet hay, and especially as they do not spout, I deny their credentials as whales; and have presented them with their passports to quit the Kingdom of [[Cetology]]."<ref>{{cite book|last=Melville|first=Herman|title=Moby-Dick; or, The Whale|chapter-url=https://archive.org/details/mobydickorwhale01melv|publisher=Richard Bentley|chapter=Footnote, Chapter 32 - Cetology|year=1851}}</ref>
A manatee called Wardell appears in the [[Animal Crossing: New Horizons]] video game. He is part of a paid [[downloadable content | downloadable content expansion]], managing and selling furniture to the player.<ref>{{cite web |last1=Fahey |first1=Mike |title=Animal Crossing Fans Are Deeply In Love With Wardell The Manatee |url=https://kotaku.com/animal-crossing-fans-are-deeply-in-love-with-wardell-th-1847886641 |website=Kotaku |date=18 October 2021 |publisher=G/O Media |access-date=14 June 2022 |archive-url=https://web.archive.org/web/20211027021018/https://kotaku.com/animal-crossing-fans-are-deeply-in-love-with-wardell-th-1847886641 |archive-date=27 October 2021}}</ref>
In [[Rudyard Kipling]]'s ''The White Seal'' (one of the stories in ''[[The Jungle Book]]''), Sea Cow, about whom the story says that he has only six cervical vertebrae, is a manatee.
== See also ==
{{portal|Mammals|Marine life}}
* [[Dwarf manatee]]
* [[Manatee of Helena]]
== References ==
{{Reflist}}
==Further reading==
* {{cite magazine|title=Man and Manatee: Can We Live Together?|magazine=[[National Geographic (magazine)|National Geographic]]|first=Alice J.|last=Hall|pages=400–418|volume=166|issue=3|date=September 1984|issn=0027-9358|oclc=643483454}}
== External links ==
{{Commons category|Trichechus}}
* [http://www.savethemanatee.org Save the Manatee] {{Webarchive|url=https://web.archive.org/web/20130510085029/http://www.savethemanatee.org/ |date=2013-05-10 }}
* [https://archive.org/details/onformstructureo00muri Murie, James ''On the Form and Structure of the Manatee'' (''Manatus americanus''), (1872) London, Zoological Society of London Year]
* [http://www.myfwc.com/manatee Florida Fish and Wildlife Conservation Commission] {{Webarchive|url=https://web.archive.org/web/20181212091434/http://myfwc.com/manatee |date=2018-12-12 }}
* [https://www.reuters.com/article/scienceNews/idUSN1233907120070413 Reuters: Florida manatees may lose endangered status] {{Webarchive|url=https://web.archive.org/web/20200925143001/https://www.reuters.com/article/scienceNews/idUSN1233907120070413 |date=2020-09-25 }}
* [https://web.archive.org/web/20061029175431/http://www.homesafe.com/manatee/index.html A website with many manatee photos]
* [http://fl.biology.usgs.gov/Manatees/manatees.html USGS/SESC Sirenia Project] {{Webarchive|url=https://web.archive.org/web/20100527085852/http://fl.biology.usgs.gov/Manatees/manatees.html |date=2010-05-27 }}
* [https://web.archive.org/web/20131103042308/http://www.sirenian.org/biblio/ ''Bibliography and Index of the Sirenia and Desmostylia'' – Dr. Domning's authoritative manatee research bibliography]
{{Sirenia}}
{{Sirenian genera|state=autocollapse}}
{{Taxonbar|from=Q42797}}
{{Authority control}}
[[Category:Manatees| ]]
[[Category:Mammal families]]
[[Category:Extant Pleistocene first appearances]]
[[Category:Taxa named by Carl Linnaeus]]
[[Category:Taxa named by Theodore Gill]]