Editing Seamount (section)

===Ecological role of seamounts===
[[File:Diurnal Flow over a Ridge - NOAA-PMEL.gif|thumb|Animations depicting current flow over seamounts and ridges.]]

Seamounts are exceptionally important to their biome ecologically, but their role in their environment is poorly understood. Because they project out above the surrounding sea floor, they disturb standard water flow, causing [[Eddy (fluid dynamics)|eddies]] and associated hydrological phenomena that ultimately result in water movement in an otherwise still ocean bottom. Currents have been measured at up to 0.9&nbsp;knots, or 48&nbsp;centimeters per second. Because of this upwelling seamounts often carry above-average [[plankton]] populations, seamounts are thus centers where the fish that feed on them aggregate, in turn falling prey to further predation, making seamounts important biological hotspots.<ref name=EoE-seamount>{{cite encyclopedia|title=Seamount|url=http://www.eoearth.org/article/Seamount|encyclopedia=[[Encyclopedia of Earth]]|access-date=24 July 2010|date=December 9, 2008}}</ref>

Seamounts provide habitats and spawning grounds for these larger animals, including numerous fish. Some species, including [[black oreo]] ''(Allocyttus niger)'' and [[blackstripe cardinalfish]] ''(Apogon nigrofasciatus)'', have been shown to occur more often on seamounts than anywhere else on the ocean floor. [[Marine mammal]]s, [[shark]]s, [[tuna]], and [[cephalopod]]s all congregate over seamounts to feed, as well as some species of [[seabird]]s when the features are particularly shallow.<ref name=EoE-seamount/>

[[File:Bubblegum coral on davidson.jpg|thumb|right|[[Grenadier (fish)|Grenadier]] fish (''Coryphaenoides sp.'') and [[Bubblegum Coral|bubblegum coral]] (''Paragorgia arborea'') on the crest of [[Davidson Seamount]]. These are two species attracted to the seamount; ''Paragorgia arborea'' in particular grows in the surrounding area as well, but nowhere near as profusely.<ref name=physorg.com>{{cite web|url=http://www.physorg.com/news153594680.html|title=Seamounts may serve as refuges for deep-sea animals that struggle to survive elsewhere|publisher=[[PhysOrg]]|date=February 11, 2009|access-date=December 7, 2009}}</ref>]]

Seamounts often project upwards into shallower zones more hospitable to sea life, providing [[habitat (ecology)|habitats]] for marine species that are not found on or around the surrounding deeper ocean bottom. Because seamounts are isolated from each other they form "undersea islands" creating the same [[biogeographical]] interest. As they are formed from [[volcanic rock]], the substrate is much harder than the surrounding [[sediment]]ary deep sea floor. This causes a different type of fauna to exist than on the seafloor, and leads to a theoretically higher degree of [[endemism]].<ref name=noaa2006-sheet>{{cite web|url=http://oceanexplorer.noaa.gov/explorations/06davidson/background/conservation/davidson_fact_sheet.pdf|title=Davidson Seamount|year=2006|publisher=[[NOAA]], [[Monterey Bay National Marine Sanctuary]]|access-date=2 December 2009}}</ref> However, recent research especially centered at [[Davidson Seamount]] suggests that seamounts may not be especially endemic, and discussions are ongoing on the effect of seamounts on endemicity. They ''have'', however, been confidently shown to provide a habitat to species that have difficulty surviving elsewhere.<ref name="PLoS ONE-2009">{{cite journal|author2=Lundsten L. |author3=Ream M., Barry J. |author4=DeVogelaere A.|date=January 7, 2009|title=Endemicity, Biogeography, Composition, and Community Structure On a Northeast Pacific Seamount|journal=[[PLoS ONE]]|volume=4|issue=1|doi=10.1371/journal.pone.0004141|last=McClain|first=Craig R.|page=e4141|pmid=19127302|pmc=2613552|editor1-last=Rands|editor1-first=Sean|bibcode = 2009PLoSO...4.4141M |doi-access=free}}</ref><ref name="DeVogelaere et. al.-2009">{{cite journal|author2=J. P. Barry |author3=G. M. Cailliet |author4=D. A. Clague |author5=A. DeVogelaere |author6=J. B. Geller|date=January 13, 2009|title=Benthic invertebrate communities on three seamounts off southern and central California|journal=[[Marine Ecology Progress Series]]|volume=374|pages=23–32|doi=10.3354/meps07745|last=Lundsten|first=L|bibcode=2009MEPS..374...23L|doi-access=free}}</ref>

The volcanic rocks on the slopes of seamounts are heavily populated by [[suspension feeder]]s, particularly [[coral]]s, which capitalize on the strong currents around the seamount to supply them with food. These coral are therefore host to numerous other organisms in a [[commensal relationship]], for example [[brittle star]]s, who climb the coral to get themselves off the seafloor, helping them to catch food particles, or small zooplankton, as they drift by.<ref>{{cite web | url=https://oceanexplorer.noaa.gov/explorations/04mountains/background/commensals/commensals.html | title=NOAA Ocean Explorer: Mountains in the Sea 2004 }}</ref> This is in sharp contrast with the typical deep-sea habitat, where deposit-feeding animals rely on food they get off the ground.<ref name=EoE-seamount/> In [[tropical zone]]s extensive coral growth results in the formation of [[atoll|coral atoll]]s late in the seamount's life.<ref name="DeVogelaere et. al.-2009" /><ref name=oceanography-census />

In addition soft sediments tend to accumulate on seamounts, which are typically populated by [[polychaete]]s ([[annelid]] [[marine worm]]s) [[oligochaete]]s ([[microdrile]] worms), and [[Gastropoda|gastropod mollusks]] ([[sea slug]]s). [[Xenophyophore]]s have also been found. They tend to gather small particulates and thus form beds, which alters sediment deposition and creates a habitat for smaller animals.<ref name=EoE-seamount/> Many seamounts also have [[hydrothermal vent]] communities, for example [[Suiyo Seamount|Suiyo]]<ref>{{cite journal|last1=Higashi|first1=Y|title=Microbial diversity in hydrothermal surface to subsurface environments of Suiyo Seamount, Izu-Bonin Arc, using a catheter-type in situ growth chamber|journal=FEMS Microbiology Ecology|year=2004|volume=47|pmid=19712321|issue=3|pages=327–336|doi=10.1016/S0168-6496(04)00004-2|display-authors=etal|doi-access=free|bibcode=2004FEMME..47..327H}}</ref> and [[Kamaʻehuakanaloa Seamount|Kamaʻehuakanaloa]] seamounts.<ref name=FeMO-Intro>{{cite web |url=http://earthref.org/cgi-bin/er.cgi?s=http://earthref.org/FEMO/loihi.htm |title=Introduction to the Biology and Geology of Lōʻihi Seamount |work= Lōʻihi Seamount |publisher= Fe-Oxidizing Microbial Observatory (FeMO) |date=2009-02-01| access-date=2009-03-02}}</ref> This is helped by geochemical exchange between the seamounts and the ocean water.<ref name=oceanography-geo />

Seamounts may thus be vital stopping points for some [[animal migration|migratory animal]]s, specifically [[whale]]s. Some recent research indicates whales may use such features as navigational aids throughout their migration.<ref name=ask-sem>{{cite web|last=Kennedy|first=Jennifer|title=Seamount: What is a Seamount?|url=http://marinelife.about.com/od/glossary/g/seamountdef.htm|publisher=[[ask.com]]|access-date=25 July 2010|archive-date=7 August 2010|archive-url=https://web.archive.org/web/20100807002637/http://marinelife.about.com/od/glossary/g/seamountdef.htm|url-status=dead}}</ref> For a long time it has been surmised that many [[Pelagic zone|pelagic animal]]s visit seamounts as well, to gather food, but proof of this aggregating effect has been lacking. The first demonstration of this conjecture was published in 2008.<ref name=marineecoprog>Morato, T., Varkey, D.A., Damaso, C., Machete, M., Santos, M., Prieto, R., Santos, R.S. and Pitcher, T.J. (2008). "Evidence of a seamount effect on aggregating visitors". ''Marine Ecology Progress'' Series 357: pages 23–32.</ref>