Home›Species›Ecosystem›Kelp ForestsEcosystemKelp ForestsMarine and Coral ReefReference and ClassificationVerifiedUnderwater forests formed by dense stands of large brown algae, most famously giant kelp, which anchors to the seafloor and grows toward the surface at rates that can exceed half a meter a day, among the fastest growth of any organism on Earth. Found along cold, nutrient rich coastlines on every continent but Antarctica, from the Pacific coast of North America to the shores of South Africa, Australia and Chile, kelp forests rank among the most productive ecosystems on the planet, sheltering fish, invertebrates and marine mammals within their canopy. The system depends on a delicate balance of predators and grazers, most famously sea otters, whose decline can let sea urchin populations explode and strip a kelp forest down to bare rock, a collapsed state known as an urchin barren.FactsKelp ForestsConnectionsSourcesOpen Questions (1 open question)Take a Related QuizComments (0)Reader Challenges (0)FactsDisputedArea (sq km)Scholarly debate50,000 1The Kelp Forest Alliance report states the true global extent is currently unresolved: observed estimates run about 50,000 to 100,000 square kilometers (5 to 10 million hectares) while modelled estimates run far higher, up to about 1,500,000 square kilometers (150 million hectares). The lower, directly observed figure is recorded here rather than a modelled upper bound.Kelp ForestsFilter Results15 entriesCommon GroupAllBox Jellyfish (Cubozoa) (1)Cephalopods (Octopus, Squid, Nautilus, Cuttlefish) (1)Gastropods (Snails And Slugs) (2)Kelps (Laminariales) (1)Lobsters And Crayfish (1)Other Bony Fish (1)Other Brown Algae (1)Perch-Like Fishes (Perciformes) (2)Red Algae (Rhodophyta) (1)Sea Stars (Asteroidea) (1)Sea Urchins and Sand Dollars (Echinoidea) (1)Shrimp And Prawns (1)TaxonomyAllAsteroidea (1)Cnidaria (1)Decapoda (1)Echinoidea (1)Gastropoda (1)Haliotis (1)Malacostraca (1)Mustelidae (1)Ochrophyta (1)Perciformes (1)Phaeophyceae (1)Plantae (1)Scorpaeniformes (1)Sepiida (1)Syngnathiformes (1)HabitatAllCoral Reef (2)Freshwater (1)Intertidal Zone (2)Kelp Forest (6)Mangrove Forest (1)Marine (4)Seagrass Meadow (1)Conservation StatusAllCritically Endangered (1)Endangered (1)Extinct (1)Least Concern (3)Near Threatened (1)Not Evaluated (2)Everyday GroupAllBox Jellyfish (Cubozoa) (1)Cephalopods (Octopus, Squid, Nautilus, Cuttlefish) (1)Gastropods (Snails And Slugs) (2)Kelps (Laminariales) (1)Lobsters And Crayfish (1)Other Bony Fish (1)Other Brown Algae (1)Perch-Like Fishes (Perciformes) (2)Red Algae (Rhodophyta) (1)Sea Stars (Asteroidea) (1)Sea Urchins and Sand Dollars (Echinoidea) (1)Shrimp And Prawns (1)DietAllCarnivore (9)Herbivore (2)Omnivore (1)Photosynthetic Autotroph (2)System (Realm)AllFreshwater (1)Marine (14)Marine and Freshwater (1)Terrestrial (1)Relationship to PeopleAllAgricultural or Structural Pest (1)Eaten or Drunk by People (2)Farmed or Commercially Raised (2)Hunted or Fished (6)Kept as Pets (1)Venomous or Dangerous to Humans (1)Living or ExtinctAllYes (12)Where It LivesAllAustralia (1)Australia (2)Canada (2)China (1)Denmark (4)France (1)Japan (1)Mexico (4)New Zealand (1)North America (1)Norway (8)Russia (1)South Africa (1)Sweden (5)United States (6)Show ResultsBrowseCompareSelect all 15AbaloneKelp ForestsBox JellyfishKelp ForestsBrown AlgaeKelp ForestsCalifornia Spiny LobsterKelp ForestsEmbiotoca jacksoniKelp ForestsGiant CuttlefishKelp ForestsGiant KelpKelp ForestsLeafy SeadragonKelp ForestsLingcodKelp ForestsNudibranchKelp ForestsPurple Sea UrchinKelp ForestsRed AlgaeKelp ForestsSea OtterKelp ForestsSkeleton ShrimpKelp ForestsSunflower Sea StarKelp ForestsConnectionsDemonstratesOcean Currents, Natural Phenomena Well-attested Kelp forests depend on current-driven coastal upwelling, such as the California Current system, to deliver the cold, nutrient-rich water kelp needs to grow at the rates that build a forest canopy.Source National Oceanic and Atmospheric Administrationtier 1Photosynthesis, Natural Phenomena Well-attested Source National Oceanic and Atmospheric Administrationtier 1HostsAbalone, Species Well-attested Source Wikidata: NudibranchAdditional Source Kelp forest (Wikipedia)Article textBox Jellyfish, Species Well-attested Source Wikipedia: Box jellyfishtier 2Brown Algae, Species Well-attested Source Brown algae - WikipediaCalifornia Spiny Lobster, Species Well-attested Source California spiny lobster (Wikipedia)Embiotoca jacksoni, Species Well-attested Source Embiotoca jacksoni (Wikipedia)Giant Cuttlefish, Species Well-attested Source Animal Diversity Web, University of Michigan Museum of Zoology: Animal Diversity Web: Sepia apamaGiant Kelp, Species Well-attested Source Wikipedia: MacrocystisLeafy Seadragon, Species Well-attested Source Leafy seadragon, WikipediaLingcod, Species Well-attested Source Lingcod (Wikipedia)Nudibranch, Species Well-attested Source Wikidata: NudibranchAdditional Source Kelp forest (Wikipedia)Article textPurple Sea Urchin, Species Well-attested Source Strongylocentrotus purpuratus, WikipediaRed Algae, Species Well-attested Source Wikidata: NudibranchAdditional Source Kelp forest (Wikipedia)Article textSea Otter, Species Well-attested Source Sea Otter (Monterey Bay Aquarium)Skeleton Shrimp, Species Well-attested Source Wikidata: NudibranchAdditional Source Kelp forest (Wikipedia)Article textSunflower Sea Star, Species Well-attested Source Wikidata: NudibranchAdditional Source Kelp forest (Wikipedia)Article textIn BiomeMarine, Biomes Well-attested Source National Oceanic and Atmospheric Administrationtier 1Open QuestionsHow much of the ocean does kelp forest actually cover?, Open Questions Well-attested Source National Oceanic and Atmospheric Administrationtier 1Sources1. Kelp Distribution, Methods Appendix (Kelp Forest Alliance)tier 1Kelp Forest AllianceSection 7.0, Kelp Distribution, Methods AppendixQuote, Section 7.0, Kelp Distribution, Methods AppendixKelp forests are found in 25 countries across all continents, but the actual area occupied by kelp forest ecosystems is currently unresolved, with observed estimates ranging from 5 M ha to modelled estimates of 150 M ha.View the SourceNational Oceanic and Atmospheric Administrationtier 1National Oceanic and Atmospheric Administrationsanctuaries.noaa.gov/visit/ecosystems/kelpdesc.html, What is kelp? sectionKelp are large brown algae, not plants, that grow in cool, nutrient-rich coastal waters. There are about 30 different species of kelp worldwide.Demonstrates: PhotosynthesisIn Biome: MarineDemonstrates: Ocean CurrentsView the SourceSea Otter (Monterey Bay Aquarium)Monterey Bay AquariumHosts: Sea OtterView the SourceStrongylocentrotus purpuratus, WikipediaHosts: Purple Sea Urchin, article text (ecosystem), EntityId 280007, target E16327Quote, Hosts: Purple Sea Urchin, article text (ecosystem), EntityId 280007, target E16327After one of its main predators, the sea otter, experienced a population decline, Strongylocentrotus purpuratus became a threat to the health of kelp forests as its own population boomed.View the SourceBrown algae - WikipediaHosts: Brown Algae, article text (ecosystem), EntityId 306682, target E16327Quote, Hosts: Brown Algae, article text (ecosystem), EntityId 306682, target E16327For instance, Macrocystis, a kelp of the order Laminariales, may reach 60 m (200 ft) in length and forms prominent underwater kelp forests that contain a high level of biodiversity.View the SourceWikipedia: Box jellyfishtier 2WikipediaHosts: Box Jellyfish, article text (ecosystem), EntityId 280943, target E16327Quote, Hosts: Box Jellyfish, article text (ecosystem), EntityId 280943, target E16327They have been spotted in near-shore habitats such as mangroves, coral reefs, kelp forests, and sandy beaches.View the SourceWikipedia: MacrocystisHosts: Giant Kelp, LeadQuote, Hosts: Giant Kelp, LeadMacrocystis is often a major component of temperate kelp forests.View the SourceCalifornia spiny lobster (Wikipedia)Hosts: California Spiny Lobster, LeadQuote, Hosts: California Spiny Lobster, LeadIt is also considered a keystone species because of their control of urchin species which would otherwise damage kelp forests.View the SourceEmbiotoca jacksoni (Wikipedia)Hosts: Embiotoca jacksoni, Distribution and habitatQuote, Hosts: Embiotoca jacksoni, Distribution and habitatThey inhabit rocky areas and reefs, eelgrass beds, and kelp forests, but can occasionally be found in sandy areas near human structures like piers or pilings.View the SourceKelp forest (Wikipedia)Hosts: Nudibranch, Article textFor example, in California, Macrocystis pyrifera forests, the nudibranch Melibe leonina, and skeleton shrimp Caprella californica are closely associated with surface canopies; the kelp perch Brachyistius frenatus, rockfish Sebastes spp.Hosts: Red Algae, Article textBeneath these kelps, a benthic assemblage of foliose red algae may occur.Hosts: Abalone, Article textare closely associated with the kelp holdfast, while various herbivores, such as sea urchins and abalone, live under the prostrate canopy; many seastars, hydroids, and benthic fishes live among the benthic assemblages; solitary corals, various gastropods, and echinoderms live over the encrusting coralline algae.Hosts: Sunflower Sea Star, Article textThe Sunflower sea star is an important keystone species which helps control sea urchin abundance, but an outbreak of Sea star wasting disease and a vulnerability to climate change has led to its critical endangerment.Hosts: Skeleton Shrimp, Article textFor example, in California, Macrocystis pyrifera forests, the nudibranch Melibe leonina, and skeleton shrimp Caprella californica are closely associated with surface canopies; the kelp perch Brachyistius frenatus, rockfish Sebastes spp.View the SourceAnimal Diversity Web, University of Michigan Museum of Zoology: Animal Diversity Web: Sepia apamaAnimal Diversity Web, University of Michigan Museum of ZoologyHosts: Giant Cuttlefish, HabitatQuote, Hosts: Giant Cuttlefish, HabitatSepia apama inhabits coral reefs, rocky reefs, kelp forests, seagrass meadows, muddy and sandy areas.View the SourceLeafy seadragon, WikipediaHosts: Leafy Seadragon, HabitatQuote, Hosts: Leafy Seadragon, HabitatThey are mostly found over sand patches in waters up to 50 m (160 ft) deep, around kelp-covered rocks and clumps of seagrass.View the SourceLingcod (Wikipedia)Hosts: Lingcod, HabitatQuote, Hosts: Lingcod, HabitatAt the juvenile life stage, lingcod live on sandy ocean bottoms with eelgrass or kelp beds near the shore.View the SourceOpen Questions (1 open question)How much of the ocean does kelp forest actually cover?Kelp beds grow along narrow, scattered stretches of cold, rocky coastline worldwide, many of them remote or difficult to survey by boat, so no single comprehensive census exists; published global-extent estimates vary by more than an order of magnitude depending on the survey method (aerial, boat-based or satellite) and the definition of kelp forest used.What would resolve this A standardized, repeated satellite remote-sensing survey of the world coastline, cross-validated against in-water surveys, of the kind marine ecologists have begun assembling only in the last few years for select regions.Marine ecology and remote sensingNational Oceanic and Atmospheric AdministrationTake a Related QuizWetlands, Reefs and Deltas: New EcosystemsCovers this kind of entry.Comments (0)No comments yet. 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