Editing Amazonian manatee (section)

==Behavior and biology==
The Amazonian manatee is the only [[sirenian]] that lives exclusively in freshwater habitat.<ref name="Amaral">{{cite journal |last1=Amaral |first1=Rodrigo S. |last2=Silva |first2=Vera M. F. da |last3=Rosas |first3=Fernando C. W. |title=Body weight/length relationship and mass estimation using morphometric measurements in Amazonian manatees Trichechus inunguis (Mammalia: Sirenia) |journal=Marine Biodiversity Records |date=27 October 2010 |volume=3 |issue=e105 |pages=4 |doi=10.1017/S1755267210000886 |doi-broken-date=1 November 2024 |bibcode=2010MBdR....3E.105A |url=https://www.cambridge.org/core/journals/marine-biodiversity-records/article/abs/body-weightlength-relationship-and-mass-estimation-using-morphometric-measurements-in-amazonian-manatees-trichechus-inunguis-mammalia-sirenia/9F96D06176D95307B1095C905B80C037|url-access=subscription }}</ref> The species relies on changes in the peripheral circulation for its primary mechanism for thermoregulation by using sphincters to deflect blood flow from areas of the body in close contact with water. They also rely on subcutaneous fat to reduce heat loss.<ref>{{cite journal |last1=Gallivan |first1=G. J. |last2=Best |first2=R. C. |last3=Kanwisher |first3=J. W. |title=Temperature Regulation in the Amazonian Manatee Trichechus inunguis |journal=Physiological Zoology |date=1983 |volume=56 |issue=2 |pages=255–262 |doi=10.1086/physzool.56.2.30156057 |jstor=30156057 |s2cid=88367955 }}</ref>

Manatees have nostrils, not blowholes like [[cetacean]]s, which close when underwater to keep water out and open when above water to breathe.<ref>{{Cite web |url=http://www.manatee-world.com/facts-about-manatees/|title = Facts about Manatees |date=2014 |access-date=8 December 2014 |website=Manatee World}}</ref> Although manatees can remain under water for extended periods, surfacing for air about every five minutes is common.<ref>{{Cite web |url=http://animals.nationalgeographic.com/animals/mammals/manatee/ |archive-url=https://web.archive.org/web/20100114005408/http://animals.nationalgeographic.com/animals/mammals/manatee/ |url-status=dead |archive-date=January 14, 2010 |title=Manatee Trichechus |access-date=8 December 2014 |website=[[National Geographic]] |date=11 November 2010}}</ref><ref>{{cite journal |last1=Gallivan |first1=G. J. |last2=Best |first2=R. C. |title=Metabolism and Respiration of the Amazonian Manatee (Trichechus inunguis) |journal=Physiological Zoology |date=1980 |volume=53 |issue=3 |pages=245–253 |doi=10.1086/physzool.53.3.30155787 |jstor=30155787 |s2cid=87433725 |url=https://www.researchgate.net/publication/290718908}}</ref> The longest documented submergence of an Amazonian manatee in captivity is 14 minutes.<ref name="Reeves96" />

Manatees make seasonal movements synchronized with the flood regime of the Amazon Basin.<ref name="Edge" /> They are found in flooded forests and meadows during the flood season, when food is abundant.<ref name="Edge" /> The Amazonian manatee has the smallest degree of rostral deflection (25° to 41°) among sirenians, an adaptation to feed closer to the water surface.<ref name="MichelleGas" /> It is both nocturnal and diurnal and lives its life almost entirely underwater.<ref name="ADW">{{cite web |last1=Gorog |first1=Antonia |title=ADW: Trichechus inunguis: INFORMATION |url=http://animaldiversity.org/accounts/Trichechus_inunguis/ |website=Animal Diversity Web |publisher=[[University of Michigan]] |access-date=9 April 2014 |date=1999}}</ref> Only its nostrils protrude from the surface of the water while it searches river and lake bottoms for vegetation.<ref name="ADW" />

The Amazonian and West Indian manatees are the only manatees known to vocalize. They have been observed vocalizing alone and with others, particularly between cows and their calves.<ref>{{cite journal |last1=Bullock |first1=Theodore H. |last2=Domning |first2=Daryl P. |last3=Best |first3=Robin C. |title=Evoked Brain Potentials Demonstrate Hearing in a Manatee (Trichechus inunguis) |journal=[[Journal of Mammalogy]] |date=1980 |volume=61 |issue=1 |pages=130–133 |doi=10.2307/1379969 |jstor=1379969}}</ref>

===Diet===
The manatees themselves feed on a variety of aquatic [[macrophytes]], including [[aroids]] (especially ''[[Pistia]]'', [[wikt:aka|aka]] "water lettuce"<ref name="ADW" /><ref>{{cite web |title=Amazon manatee &#124; WWF |url=http://wwf.panda.org/about_our_earth/species/profiles/mammals/amazon_manatee/|website=wwf.panda.org |publisher=WWF - World Wide Fund For Nature| access-date=29 March 2018 |date=2017}}</ref>), grasses, [[bladderworts]], [[hornworts]], [[Nymphaeaceae|water lilies]], and particularly, [[Eichhornia crassipes|water hyacinths]].<ref name="bibdigital.epn.edu.ec">{{cite journal |last1=Timm |first1=Robert M. |last2=Albuja |first2=Luis |last3=Clauson |first3=Barbara L. |title=Ecology, Distribution, Harvest, and Conservation of the Amazonian Manatee Trichechus inunguis in Ecuador |journal=Biotropica |date=1986 |volume=18 |issue=2 |pages=150–156 |doi=10.2307/2388757 |jstor=2388757 |bibcode=1986Biotr..18..150T |url=http://bibdigital.epn.edu.ec/handle/15000/4797 |hdl=1808/6920 |hdl-access=free}}</ref> They are also known to eat [[Arecaceae|palm]] fruits that fall into the water.<ref name="ADW" /> Maintaining a herbivorous diet, the manatee has a similar post-gastric digestive process to that of the horse.<ref name="MichelleGas" /> The manatee consumes approximately 8% of its body weight in food per day.<ref name="MichelleGas">{{cite journal |last1=Pazin-Guterres |first1=Michelle |title=Feeding Ecology of the Amazonian Manatee (Trichechus inunguis) in the Mamirauá and Amanã Sustainable Development Reserves, Brazil. |journal=Aquatic Mammals |date=2014 |volume=40 |issue=2 |pages=139–149 |doi=10.1578/AM.40.2.2014.139 |bibcode=2014AqMam..40..139G |url=https://www.researchgate.net/publication/262685494}}</ref>

During the July–August dry season when water levels begin to fall, some populations become restricted to the deep parts of large lakes, where they often remain until the end of the dry season in March.<ref name="Edge" /> They are thought to fast during this period, their large fat reserves and low metabolic rates – only 36% of the usual placental mammal metabolic rate – allowing them to survive for up to seven months with little or no food.<ref name="Edge" />

=== Reproduction and lifecycle ===
The Amazonian manatee is a seasonal breeder with a gestational period of 12–14 months and a prolonged calving period. Most births take place between December and July, with about 63% between February and May, during a time of rising river levels in their native region.<ref>{{cite journal |last1=Best |first1=Robin C. |title=Seasonal Breeding in the Amazonian Manatee, Trichechus inunguis (Mammalia: Sirenia) |journal=Biotropica |date=1982 |volume=14 |issue=1 |pages=76–78 |doi=10.2307/2387764 |jstor=2387764 |bibcode=1982Biotr..14...76B}}</ref> After the calf is born, it will begin to eat while staying with its mother for 12 – 18 months.<ref name="Files" >{{cite web |title=Amazonian Manatee |url=http://www.theanimalfiles.com/mammals/dugong_manatees/amazonian_manatee.html |website=theanimalfiles.com |access-date=24 October 2014}}</ref>

Wild individuals have a lifespan of about 30 years.<ref name="ADW" /> The record captive lifespan is 17 years.<ref>{{cite journal |last1=Morales |first1=Patricia |year=1986 |title=The Life and Death of an Amazon Manatee |url=https://www.vin.com/apputil/content/defaultadv1.aspx?id=3981692&pid=11103 |journal=Proceedings of the International Association of Aquatic Animal Medicine |volume=1 |issue=3 |pages=43–48}}</ref>