{{Short description|Species of fish}} {{Speciesbox | image = stoplight-parrotfish.jpg | image_caption = | image2 = Sparisoma viride 404381982 (cropped).jpg | image2_caption = Terminal phase (top)<br />Initial phase (bottom) | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Rocha, L.A. |author2=Choat, J.H. |author3=Clements, K.D. |author4=Russell, B. |author5=Myers, R. |author6=Lazuardi, M.E. |author7=Muljadi, A. |author8=Pardede, S. |author9=Rahardjo, P. |date=2012 |title=''Sparisoma viride'' |volume=2012 |article-number=e.T190734A17779745 |doi=10.2305/IUCN.UK.2012.RLTS.T190734A17779745.en |access-date=19 November 2021}}</ref> | taxon = Sparisoma viride | authority = (Bonnaterre, 1788) | synonyms = *''Scarus viridis'' <small>Bonnaterre, 1788</small> | synonyms_ref = <ref name = Fishbase>{{Fishbase|Sparisoma|viride|month=December|year=2019}}</ref> }}
The '''stoplight parrotfish''' (''Sparisoma viride'') is a species of marine ray-finned fish, a parrotfish from the family Scaridae, inhabiting coral reefs in Florida, Caribbean Sea, Gulf of Mexico, Bermuda and as far south as Brazil.<ref name="reeffish">{{cite book | last =Humann, DeLoach | title =Reef Fish Identification - Florida Caribbean Bahamas | publisher =New World Publications, Inc. | year =2002 | isbn =1-878348-30-2}}</ref> It mainly feeds on algae by scraping and excavating it with its teeth. Like most of its relatives, it is able to change sex.
The common name, '''stoplight''', comes from the marked yellow spot near the pectoral fin, which is clearly visible only in specimens in the terminal phase.
== Sex Change & Coloring == thumb|Terminal phase, in Florida The stoplight parrotfish is a protogynous hermaphrodite that shows full sexual dichromatism, meaning that it changes its sex from female to male during its lifespan, and its color changes with its sex change.<ref name=":0">{{Cite journal|last1=Bruggemann|first1=J. Henrich|last2=van Oppen|first2=Madeleine J.H.|author-link2=Madeleine van Oppen|last3=Breeman|first3=Anneke M.|date=March 17, 1994|title=Foraging by the stoplight parrotfish Sparisoma viride. I. Food selection in different, socially determined habitats|url=https://www.int-res.com/articles/meps/106/m106p041.pdf|journal=Marine Ecology Progress Series|volume=106|pages=41–55|doi=10.3354/meps106041 |bibcode=1994MEPS..106...41B }}</ref> The sex change is most likely due to the control of hormones, in particular, 11-ketetestosterone (11-KT).<ref name=":1" /> The timing of the sex change can vary depending on population density, growth, and mortality rates. Early sex changes may occur if sexually active individuals have a higher mortality rate or have reduced growth rates.<ref name=":2">{{Cite journal|last1=Paddack|first1=M. J.|last2=Sponaugle|first2=S.|last3=Cowen|first3=R. K.|date=December 2009|title=Small-scale demographic variation in the stoplight parrotfish Sparisoma viride|url=http://doi.wiley.com/10.1111/j.1095-8649.2009.02451.x|journal=Journal of Fish Biology|language=en|volume=75|issue=10|pages=2509–2526|doi=10.1111/j.1095-8649.2009.02451.x|pmid=20738505 |bibcode=2009JFBio..75.2509P |url-access=subscription}}</ref>
The stoplight parrotfish has 3 life phases: juvenile, initial, and terminal. The colors of the stoplight parrotfish in the initial phase, when it could be either a male or a female, are dramatically different from those in the terminal phase, when it is definitely a male.<ref name=":1">{{Cite journal|last1=Cardwell|first1=J.R.|last2=Liley|first2=N.R.|date=1991|title=Hormonal control of sex and color change in the stoplight parrotfish, Sparisoma viride|journal=General and Comparative Endocrinology|language=en|volume=81|issue=1|pages=7–20|doi=10.1016/0016-6480(91)90120-U|pmid=2026318}}</ref> During the juvenile and initial phase, the parrotfishes are colored brown with a red belly. During the terminal phase, the parrotfishes are a vivid green color with yellow spots on the tail base of their caudal fin.<ref name=":0" /><ref name=":3">{{Cite journal|last=Hanley|first=Fred|date=1984-12-14|title=Time-budgeting and foraging strategy of the stoplight parrotfish Sparisoma viride Bonnaterre, in Jamaica|journal=Journal of Experimental Marine Biology and Ecology|language=en|volume=83|issue=2|pages=159–177|doi=10.1016/0022-0981(84)90043-1|bibcode=1984JEMBE..83..159H |issn=0022-0981}}</ref> However, some males do not change color at the same time they change sex, therefore becoming female-mimic males (also termed initial phase males). During the initial phase, about 4% of the smaller parrotfish individuals are males.<ref name=":3" />
== Habitat == The stoplight parrotfish inhabit shallow coral reefs not disturbed by humans in Florida, the Caribbean Sea, Gulf of Mexico, Bermuda and Brazil.<ref name=":0" /> They are only active during the day and spend most of their time foraging, swimming, or hovering.<ref name=":0" /><ref name=":3" /> At night, they remain hidden under coral boulders.<ref name=":0" /> Large individuals typically spend more time swimming and spend a significant amount of time sheltering among crevices,<ref name=":3" /> while smaller individuals spend more time hovering.<ref name=":3" /> The stoplight parrotfish have a high density in areas of higher algal production. As adults, the stoplight parrotfish are site-attached with limited home ranges.<ref name=":2" />
In the Florida Keys, the stoplight parrotfish were found most frequently in areas with high cover of the macroalgae ''Dictyota''. They have also been found to select for the branching coral ''Porites porites'', however ''Dictyota'' are an effective recruitment substrate when branching corals are not available.<ref name=":4">{{Cite journal|last1=Paddack|first1=Mj|last2=Sponaugle|first2=S|date=2008-10-13|title=Recruitment and habitat selection of newly settled Sparisoma viride to reefs with low coral cover|url=http://www.int-res.com/abstracts/meps/v369/p205-212/|journal=Marine Ecology Progress Series|language=en|volume=369|pages=205–212|doi=10.3354/meps07632|issn=0171-8630|doi-access=free|bibcode=2008MEPS..369..205P }}</ref>
Due to its abundance in the Caribbean, the stoplight parrotfish are very ecologically important there.<ref name=":2" />
=== Onshore and Offshore Reefs === Onshore coral reefs have a greater proportion of older juvenile fish, suggesting that the mortality and/or emigration of adults is more common onshore.<ref name=":4" /> Stoplight parrotfishes on offshore coral reefs have a greater average standard length, greater mean asymptotic size, and live twice as long as other fish from onshore coral reefs. Fish onshore were no older than 4 years, while the fish offshore reached 7–8 years. The age difference between offshore and onshore reefs could be due to the stoplight parrotfish migrating from onshore to offshore reefs with age, however, there is no evidence of ontogenetic migration.<ref name=":2" />
== Feeding == [[File:Stoplight parrotfish Sparisoma viride terminal phase.jpg|thumb|Terminal phase with a queen parrotfish (left), in Bonaire]] The stoplight parrotfish employs a scraping and excavating grazing mode and feeds almost exclusively on algae that are associated with dead coral substrates.<ref name=":0" /> They have higher grazing rates and assimilation efficiencies in areas with high-quality food.<ref name=":2" />
Their preferred food types are large, sparse turfs growing on carbonate substrates that are inhibited by endolithic algae. Algae have high levels of proteins, a high energetic value, along with a high yield, making it preferable to the stoplight parrotfish. As facultative corallivores, adult fish will occasionally feed on living corals (mainly ''Montastrea annularis''). In healthy coral reef environments, the detriment of coral-feeding by parrotfish tends to be offset by the benefits of their algal feeding. In declining coral reefs, however, corallivory by parrotfish may act synergystically with other stressors to depress coral growth and recovery.<ref>{{Cite journal |last1=Rotjan |first1=Randi D. |last2=Lewis |first2=Sara M. |date=2008-09-11 |title=Impact of coral predators on tropical reefs |url=https://www.int-res.com/abstracts/meps/v367/p73-91/ |journal=Marine Ecology Progress Series |language=en |volume=367 |pages=73–91 |doi=10.3354/meps07531 |issn=0171-8630|doi-access=free |bibcode=2008MEPS..367...73R |url-access=subscription }}</ref> Crutose corallines are not preferred, whether or not they do or do not have algal turf.<ref name=":0" />
Their foraging strategy is called "search and nip" and they spend short bouts of energy on swimming, feeding, and hovering.<ref name=":3" />
== Growth rate == The stoplight parrotfish grow continuously throughout life<ref name=":0" /> and their growth rate increases with higher food availability.<ref name=":2" /> The largest class of stoplight parrotfish is when they are in their terminal phase.<ref name=":2" />
Its typical length is between {{convert|1|and(-)|1.5|ft|cm|abbr=on|round=5}},<ref name="reeffish" /> but it can reach up to {{convert|64|cm|ft|abbr=on|order=flip|0}}.<ref name="Fishbase" /> It is normally found during the day at depths between {{convert|15|and(-)|80|ft|abbr=on|round=5}},<ref name="reeffish" /> but can be found from {{convert|3|to(-)|50|m|ft|abbr=on|order=flip|round=5}}<ref name="Fishbase" />
== Reproduction == Stoplight parrotfishes engage in reproductive activity throughout the year.<ref name=":0" /> They are harem-forming fishes and territorial terminal phase males defend areas that are shared with 1-14 initial phase parrotfishes, with whom they mate. There is more territorial defense in areas with high-quality food.<ref name=":2" /> Single terminal phase males also defend the deeper reef from conspecifics.<ref name=":0" />
Stoplight parrotfish males will often control territories containing many sexually mature females to breed with. Males that have territories and those that don't will have vastly different levels of testosterone.<ref>Cardwell, J. "Androgen Control of Social Status in Males of a Wild Population of Stoplight Parrotfish, Sparisoma Viride (Scaridae)*1." Hormones and Behavior, vol. 25, no. 1, Mar. 1991, pp. 1–18., doi:10.1016/0018-506x(91)90035-g.</ref>
==References== {{Reflist}}
==External links== * {{sealifephotos|273780}}
{{Taxonbar|from=Q2700140}}
stoplight parrotfish Category:Fish of the Caribbean Category:Fish of the Western Atlantic Category:Taxa named by Pierre Joseph Bonnaterre stoplight parrotfish Category:Fish of Cuba Category:Fish of the Dominican Republic