View source for Marine otter

{{short description|Species of South American mammal (Lontra felina)}}
{{distinguish|sea otter}}
{{Use dmy dates|date=April 2024}}
{{speciesbox
| name = Marine otter
| image = Lfelina.jpg
| image_caption = In Huachipa Zoo, [[Peru]]
| status = EN
| status_system = IUCN3.1
| status_ref = <ref name=Redlist/>
 | status2 = CITES_A1 
 | status2_system = CITES 
 | status2_ref = <ref>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref>
| genus = Lontra
| species = felina
| authority = ([[Juan Ignacio Molina|Molina]], 1782)
| range_map = Marine Otter area.png
| range_map_caption = Marine otter range
}}

The '''marine otter''' ('''''Lontra felina''''') is a rare and relatively unknown [[South America]]n [[mammal]] of the weasel family ([[Mustelidae]]).  The [[scientific name]] means "feline otter", and in [[Spanish language|Spanish]], the marine otter is also often referred to as {{Lang|es|gato marino}}: "marine cat".  The marine otter (while spending much of its time out of the water) only lives in saltwater, coastal environments and rarely ventures into [[fresh water]] or [[Estuary|estuarine]] habitats. This saltwater exclusivity is unlike most other otter species, except for the almost fully [[Aquatic animal|aquatic]] [[sea otter]] (''Enhydra lutris'') of the North Pacific.

== Description ==

The marine otter is one of the smallest otters and the smallest marine mammal,<ref name="BBCTH">{{cite web|url=http://www.bbc.co.uk/programmes/b06s11yb|title=The Hunt: Race Against Time (Coasts)|access-date=2015-12-06|publisher=[[BBC]]}}</ref><ref name="BBCW">{{cite web|url=http://www.bbc.co.uk/programmes/b06s11yb|title=Chilean marine otter: Meet the sea cat|date=30 March 2011|access-date=31 May 2018|work=[[BBC Wildlife]]|publisher=[[Immediate Media Company]]}}</ref> measuring {{convert|87|to|115|cm|in|abbr=on}} from the nose to the tip of the tail and weighs {{Convert|3|to|5|kg|lbs|abbr=on}}. The tail measures {{Convert|30|to|36|cm|in|abbr=on}}.<ref name="MMotW">{{cite book|last1=Jefferson|first1=Thomas A.|last2=Webber|first2=Marc A.|last3=Pitman|first3=Robert L.|title=Marine Mammals of the World: A Comprehensive Guide to their Identification|publisher=[[Academic Press]]|place=San Diego|year=2015|isbn=978-0124095922|pages=539–541}}</ref><ref>{{Cite web|url=http://eol.org/pages/311559/overview|title=Marine Otter – Lontra felina|publisher=[[Encyclopedia of Life]]|date=n.d.|access-date=31 May 2018}}</ref> Its fur is coarse, with [[Fur#Composition|guard hair]]s measuring up to {{Convert|2|cm|in|abbr=on}} in length covering dense, insulating [[Fur#Composition|underfur]]. The marine otter is dark brown above and on the sides, and fawn on the throat and underside.<ref name="MMotW"/>

The marine otter has [[Interdigital webbing|webbed]] [[paw]]s and strong [[claw]]s. The ventral side (underside) of the paws are partially covered in fur. It has 36 [[Tooth|teeth]] and a [[Dentition#Dental formula|dental formula]] of {{DentalFormula|upper=3.1.3-4.1|lower=3.1.3.2}}.
The teeth are developed for slicing instead of crushing. The marine otter does not display [[sexual dimorphism]].<ref name="MMotW"/>

[[File:Lontra felina Werner.JPG|alt=Depiction of marine otter, including skull and dental structure.|none|thumb|357x357px|Art by Jacques Christophe Werner, 30 April 1848]]

== Distribution and habitat ==

Marine otters are found in [[littoral]] areas of southwestern South America, close to shore and in the [[intertidal]] areas of northern [[Peru]] (from the port of [[Chimbote]]), along the entire coast of [[Chile]], and the extreme southern reaches of [[Argentina]].<ref name=Redlist>{{cite iucn |author=Mangel, J. |author2=Alfaro-Shigueto, J. |author3=Verdi, R. |author4=Rheingantz, M.L. |year=2022 |title=''Lontra felina'' |volume=2022 |page=e.T12303A215395045 |doi=10.2305/IUCN.UK.2022-2.RLTS.T12303A215395045.en |access-date=17 June 2024}}</ref> Occasional vagrant sightings still occur as far afield as the [[Falkland Islands]].{{Citation needed|date=January 2025}}

The marine otter mainly inhabits rocky shorelines with abundant seaweed and [[kelp]], and infrequently visits estuaries and freshwater rivers. It appears to select habitats with surprisingly high exposure to strong swells and winds, unlike many other otters, which prefer calmer waters. Caves and crevices in the rocky shorelines may provide them with the cover they need, and often a [[Otter|holt]] will have no land access at high tide. Marine otters avoid sandy beaches.

== Behavior and ecology ==
[[File:Chungungos, Reserva nacional Pingüino de Humboldt.jpg|alt=Two marine otters socializing.|thumb|243x243px|Two marine otters socializing]]
Rocky intertidal zones with natural crevices are ideal for marine otter dens and feeding areas. Because most of their time is spent hidden in caves, their behavior is difficult to observe.

Marine otters actively avoid humans. In response to human activity, they will spend less time on coasts and stray from their dens during the day to fissures inaccessible to humans.<ref name=":0">{{Cite journal |last1=Gutiérrez |first1=Laura |last2=Vargas |first2=Fernanda |last3=Pinto |first3=Pía |last4=Troncoso |first4=Walter |last5=Santos-Carvallo |first5=Macarena |last6=Sepúlveda |first6=Maritza |date=2019-03-14 |title=Impact of human activities in habitat use and activity patterns of the marine otter (Lontra felina) in central Chile |journal=Latin American Journal of Aquatic Research |volume=47 |issue=1 |pages=122–128 |doi=10.3856/vol47-issue1-fulltext-13 |s2cid=92484935 |issn=0718-560X |doi-access=free |bibcode=2019LAJAR..47..122G }}</ref> Though generally avoidant of humans, their inhabitance of fishing villages is an indicator of the marine otter's ability to adapt to urbanization.<ref>{{Cite journal |last1=Ortiz-Alvarez |first1=Clara |last2=Alfaro-Shigueto |first2=Joanna |last3=Mangel |first3=Jeffrey C. |date=2021-02-24 |title=Insights into marine otter ( Lontra felina ) distribution along the Peru coastline |url=https://onlinelibrary.wiley.com/doi/10.1111/mms.12789 |journal=Marine Mammal Science|volume=37 |issue=3 |pages=993–1007 |doi=10.1111/mms.12789 |bibcode=2021MMamS..37..993O |s2cid=233918836 |issn=0824-0469|url-access=subscription }}</ref>

=== Reproduction ===
Marine otters may be monogamous or polygamous, and breeding occurs in December or January. Litters of two to five pups are born in January, February or March after a [[gestation]] period of 60 to 70 days. The pups remain with their mother for about 10 months of parental care, and can sometimes be seen on the mother's belly as she swims on her back, a practice similar to that of the [[sea otter]]. Parents bring food to the pups and teach them to hunt.

=== Feeding ===
Studies have shown latitudinal variations in diet, feeding periods, and dive time throughout the marine otter's distribution. Marine otters of southern Chile primarily feed on [[fish]], while those in northern Chile mostly feed on [[crustacean]]s and [[Mollusca|mollusks]].<ref>{{Cite journal |last1=Medina-Vogel |first1=Gonzalo |last2=Rodriguez |first2=Claudio Delgado |last3=Ricardo E. Alvarez |first3=P. |last4=Jose Luis Bartheld |first4=V. |title=Feeding Ecology of the Marine Otter (''Lutra felina'') in a Rocky Seashore of the South of Chile |date=2004-01-01 |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1748-7692.2004.tb01144.x |journal=Marine Mammal Science|volume=20 |issue=1 |pages=134–144 |doi=10.1111/j.1748-7692.2004.tb01144.x |bibcode=2004MMamS..20..134M |issn=0824-0469|url-access=subscription }}</ref> The otters on [[Isla La Vieja]], [[Peru]] presumably prey on a colony of [[Peruvian diving petrel]]s regularly.<ref name=":1">Valqui, Juan (2012-03). "[https://www.researchgate.net/publication/228469499_The_marine_otter_Lontra_felina_Molina_1782_A_review_of_its_present_status_and_implications_for_future_conservation#pf9 The marine otter Lontra felina (Molina, 1782): A review of its present status and implications for future conservation]". Mammalian Biology. 77 (2): 75–83. doi:10.1016/j.mambio.2011.08.004. ISSN 1616-5047.</ref> In January 2009, one was seen preying on [[magellanic flightless steamer duck]] chick in [[Puñihuil]].<ref name=":1" /> The species shows [[Opportunism|opportunistic]] feeding behavior, sometimes eating small [[mammal]]s and even fruit of plants like ''[[Greigia sphacelata]]'' and ''[[Fascicularia bicolor]].''<ref name=":1" />

== Taxonomy ==
The marine otter is of the [[Otter|Lutrinae]], a subfamily of Mustelidae. Its exact [[Taxonomy (biology)|taxonomy]] has been debated due to lack of data. A phylogenetic study by C. G. Van Zyll De Jong in 1987 proposed the following phenogram of the lutrinae, based on [[Morphology (biology)|morphological]] data.
{{clade sequential|[[Asian small-clawed otter|Aonyx cinereus]]|'''Lontra felina'''|[[North American river otter|Lontra canadensis]]|[[Neotropical otter|Lontra longicaudis]]|[[Southern river otter|Lontra provocax]]}}Jong's proposed phenogram implied that the marine otter descended from the [[Asian small-clawed otter]], and its closest relative being the [[North American river otter]].<ref>{{Cite journal |last=Jong |first=C. G. van Zyll de |date=1987-10-01 |title=A phylogenetic study of the Lutrinae (Carnivora; Mustelidae) using morphological data |url=http://www.nrcresearchpress.com/doi/10.1139/z87-383 |journal=Canadian Journal of Zoology|volume=65 |issue=10 |pages=2536–2544 |doi=10.1139/z87-383 |bibcode=1987CaJZ...65.2536J |issn=0008-4301|url-access=subscription }}</ref> A 2004 study contradicted Jong's research. The following was proposed as a part of the taxonomy of the Mustelidae, based on [[Cytochrome b|cytochrome ''b'']] sequences.<ref>{{Cite journal |last1=Marmi |first1=Josep |last2=Lopez-Giraldez |first2=Juan Francisco |last3=Domingo-Roura |first3=Xavier |date=6 November 2004 |title=Phylogeny, evolutionary history and taxonomy of the Mustelidae based on sequences of the cytochrome b gene and a complex repetitive flanking region |url=https://onlinelibrary.wiley.com/doi/10.1111/j.0300-3256.2004.00165.x |journal=Zoologica Scripta|volume=33 |issue=6 |pages=481–499 |doi=10.1111/j.0300-3256.2004.00165.x |s2cid=85818256 |issn=0300-3256|url-access=subscription }}</ref>

{{clade sequential|[[North American river otter|Lontra canadensis]]|[[Neotropical otter|Lontra longicaudis]]|'''Lontra felina'''}}

== Threats ==
Human activity on coastlines poses disturbance to marine otters. Humans introduce domestic animals which may also disturb their dens.<ref name=":0" /> Humans, as well as domesticated species, may expose a marine otter population to disease. Marine otters may be entangled in fishing nets and die.<ref name=":1" />

[[Microplastics]] have been found in the scat of marine otters.<ref>{{Cite journal |last1=Santillán |first1=Luis |last2=Saldaña-Serrano |first2=Miguel |last3=Enrique De-La-Torre |first3=Gabriel |date=2020-05-13 |title=First record of microplastics in the endangered marine otter (Lontra felina) |journal=Mastozoología Neotropical |volume=27|pages=211–215 |doi=10.31687/saremMN.20.27.1.0.12 |s2cid=225632904 |doi-access=free }}</ref> The effects of microplastics in marine mammals are still unclear.

===Competition and predation===
[[Gull]]s and [[South American sea lion]]s may compete with marine otters for prey, the latter known to also attack the otters.<ref name=":1" /> [[Orca]]s and sharks allegedly prey on the otters, though direct attacks have not been observed.<ref name=":1" />

===Parasites===
Marine otters are known to be susceptible to ''[[Toxoplasma gondii]]'' infection along the northern and central coast of [[Chile]],<ref name=":2">{{Cite journal |last1=Calvo-Mac |first1=Carlos |last2=Gutleb |first2=Arno C. |last3=Contal |first3=Servane |last4=Ilukewitsch |first4=Vannessa |last5=Muñoz-Zanzi |first5=Claudia |last6=Medina-Vogel |first6=Gonzalo |date=2020-10-01 |title=Exposure to Toxoplasma gondii in Marine Otters (Lontra felina) and Domestic Cats (Felis catus) in an Arid Environment in Chile |url=https://doi.org/10.7589/2019-10-269 |journal=Journal of Wildlife Diseases |volume=56 |issue=4 |pages=962–964 |doi=10.7589/2019-10-269 |pmid=32609602 |s2cid=220307894 |issn=0090-3558|url-access=subscription }}</ref> though ''T. gondii'' [[seroprevalence]] in this otter species is lower than in other aquatic [[Mustelidae|mustelids]] such as the [[southern river otter]] and [[American mink]] in southern Chile,<ref>{{Cite journal |last1=Barros |first1=Macarena |last2=Cabezón |first2=Oscar |last3=Dubey |first3=Jitender P. |last4=Almería |first4=Sonia |last5=Ribas |first5=María P. |last6=Escobar |first6=Luis E. |last7=Ramos |first7=Barbara |last8=Medina-Vogel |first8=Gonzalo |date=2018-06-20 |title=Toxoplasma gondii infection in wild mustelids and cats across an urban-rural gradient |journal=PLOS ONE|volume=13 |issue=6 |pages=e0199085 |doi=10.1371/journal.pone.0199085 |issn=1932-6203 |pmc=6010287 |pmid=29924844|bibcode=2018PLoSO..1399085B |doi-access=free }}</ref> likely because of the general dryness of the former environment.<ref name=":2" /> [[Nematode]]s and [[Acanthocephala|acantocephalans]] are also known [[endoparasites]] of this species.<ref name=":1" />

== Conservation status ==

Marine otters are rare and are protected under Peruvian, Chilean, and Argentine law.<ref name=Redlist/> In the past, they were extensively hunted both for their fur and due to perceived competition with fisheries. Hunting extirpated them from most of [[Argentina]] and the [[Falkland Islands]]. Poaching is still a problem, but one of unknown magnitude. It is unknown how many marine otters exist in the wild or what habitats should be preserved to encourage their recovery. Marine otters were listed under [[CITES]] Appendix I in 1976, and are listed as endangered by the U.S. Department of the Interior.

== References ==
{{Reflist}}

==External links==
* {{Commons category-inline|Lontra felina|''Lontra felina''}}
* {{Wikispecies-inline|Lontra felina|''Lontra felina''}}
* [http://www.otter.org/ International Otter Survival Fund]

{{Carnivora|M.}}
{{Taxonbar|from=Q644224}}

[[Category:Lontra|marine otter]]
[[Category:Marine mammals]]
[[Category:Mammals of Argentina]]
[[Category:Mammals of Chile]]
[[Category:Fauna of the Falkland Islands]]
[[Category:Carnivorans of South America]]
[[Category:Marine fauna of South America]]
[[Category:Western South American coastal fauna]]
[[Category:Endangered animals]]
[[Category:Endangered biota of South America]]
[[Category:Mammals described in 1782]]