Editing Manatee (section)

===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|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| bibcode=2012JExpB.215.1442G }}</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|url-access = subscription}}</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>