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Sunbeams through a giant kelp forest canopy, with schooling fish, a garibaldi and sea urchins on the reef below

The Kelp & Ocean Encyclopedia

Every forest is made of individuals.

Meet the species of the kelp forest — the canopy-builders, the grazers, the predators and the wanderers. Each profile pairs natural history with the structured facts divers, students and scientists actually look for.

Browse 322 profilesExplore the Coastal Atlas
Jump toKelp & seaweedsInvertebratesFishesSeabirdsMarine mammals322 profiles · growing weekly

Kelp & seaweeds

The architects and their neighbours — the kelps that build the canopy, and the seaweeds that fill the understory and the kitchen.

39 profiles · View group →

Chain bladder kelp

Stephanocystis osmundacea (syn. Cystoseira osmundacea)

The canopy with a rope of pearls — California’s mid-storey fucoid that keeps reef structure standing when giant kelp thins

9 min read · Kelp & seaweeds

Chilean huiro

Lessonia trabeculata

Builder of Chile’s great subtidal kelp forests — and feedstock of the global alginate trade

9 min read · Kelp & seaweeds

Cochayuyo, Chile’s edible bull kelp

Durvillaea antarctica

Chile’s great market kelp — food and industry today, ocean-going raft for whole communities when it tears free

9 min read · Kelp & seaweeds

Coralline algae

Order Corallinales — many species

The living pink cement — and the settlement call for urchins, abalone and kelp

10 min read · Kelp & seaweeds

Crustose coralline algae (CCA)

Order Corallinales — many encrusting species

The pink cement that welds reefs together — and the settlement cue abalone, urchins and corals grow up waiting for

10 min read · Kelp & seaweeds

Cystoseira canopy algae

Cystoseira sensu lato (now split across several genera)

The Mediterranean’s kelp-forest equivalent — perennial canopy fucoids whose dispersal is so poor that lost stands cannot walk back

9 min read · Kelp & seaweeds

Dead man’s bootlace

Chorda filum

A true kelp disguised as a string — an annual, drifting cord forest that shelters young fish along sheltered shores

8 min read · Kelp & seaweeds

Sunlit eelgrass meadow: bright green blades swaying above pale sand, with the dark edge of a kelp forest in the hazy background.

Eelgrass

Zostera marina

A true flowering plant beside the kelp — nursery, sediment-anchor and blue-carbon meadow

8 min read · Kelp & seaweeds

Southern sea palm

Eisenia arborea

The sea palm of the warm edge — a surf-zone kelp carrying its forest into Baja

9 min read · Kelp & seaweeds

Gelidium (agar weed)

Gelidium spp.

The wild-harvested source of the world’s finest laboratory-grade agar

9 min read · Kelp & seaweeds

Irish moss

Chondrus crispus

The little red alga that thickened a century of kitchens — the original carrageenan seaweed

9 min read · Kelp & seaweeds

Ogonori

Gracilaria spp.

The agar weed — the red alga genus behind agar-agar and much of microbiology’s benchwork

9 min read · Kelp & seaweeds

Ribbon kelp

Alaria marginata

The golden streamer of the surge zone — a seasonal pulse of food and forage at the low shore

7 min read · Kelp & seaweeds

Sargassum horneri

Sargassum horneri (recently reassigned as S. filicinum)

The kelp coast’s floating invader — a fast-spreading canopy competitor that sheds its fertile tops and drifts onward

9 min read · Kelp & seaweeds

Underwater view inside a sea bamboo forest off South Africa's Cape coast, long golden stipes rising from the reef to a sunlit surface canopy of fronds

Sea bamboo, the Cape’s giant kelp

Ecklonia maxima

The forest builder of the Cape — the canopy everything else lives beneath

9 min read · Kelp & seaweeds

Sea cabbage

Hedophyllum sessile

The low shore’s own kelp — first plate for grazers as the tide falls

9 min read · Kelp & seaweeds

Sea lettuce

Ulva lactuca and relatives

The harbour opportunist — a fast green that can turn nutrient runoff into “green tides”

8 min read · Kelp & seaweeds

Sea palm, storm specialist

Postelsia palmaeformis

An annual that only wins where waves hit hardest — the intertidal’s own kelp

8 min read · Kelp & seaweeds

Sea spaghetti

Himanthalia elongata

The Atlantic’s ribbon belt — an edible low-shore canopy that comes back as buttons every year

9 min read · Kelp & seaweeds

Southern bull kelp

Durvillaea spp.

The southern surf specialist — and the ocean’s great rafter of life

9 min read · Kelp & seaweeds

Underwater view of a stalked kelp forest: slender woody stipes rising from pink coralline-encrusted rock, each crowned with brown blades, under shafts of teal sunlight

Stalked kelp, the old growth

Pterygophora californica

The patient one — long-lived understory kelp sheltering life while faster kelps rise and fall around it

9 min read · Kelp & seaweeds

Tangle kelp (cuvie)

Laminaria hyperborea

Europe’s great subtidal forest-former — Norway’s “tare” coasts are built of it

8 min read · Kelp & seaweeds

Turf algae

Mixed turf-forming red, green and brown algae

The resilient under-storey rival — a fuzzy carpet that can block kelp recovery and hold a reef in a degraded state

9 min read · Kelp & seaweeds

Sieve kelp

Agarum clathratum

The holey kelp of the far north — a puzzle of drag and light in cold water

8 min read · Kelp & seaweeds

Winged kelp

Alaria esculenta

The wave-exposure specialist of Atlantic shores — and a mild, edible kelp

8 min read · Kelp & seaweeds

Acid kelp

Desmarestia spp.

A pioneer brown seaweed carrying literal acid in its cells — where Desmarestia stands, grazers tread lightly

8 min read · Kelp & seaweeds

Feather boa kelp

Egregia menziesii

Mid-water drapery whose flotilla of floats shelters a miniature rainforest of small life

7 min read · Kelp & seaweeds

Dulse

Palmaria palmata

Red alga of the kelp understory — and the famous “bacon of the sea”

9 min read · Kelp & seaweeds

Five-ribbed kelp

Costaria costata

The North Pacific’s broad mid-story kelp, bending the swell for smaller life

8 min read · Kelp & seaweeds

Nori

Pyropia and Porphyra species

Red algal cousins of the kelp forest edge; the seaweed of sushi fame

9 min read · Kelp & seaweeds

Elk kelp

Pelagophycus porra

The deep-edge canopy kelp — forest where giant kelp can’t root

7 min read · Kelp & seaweeds

Broad, dark kombu fronds swaying in cold, sunlit water over a rocky reef off Hokkaido

Kombu

Saccharina japonica

A wild forest kelp and the backbone of the dashi tradition

9 min read · Kelp & seaweeds

Wakame

Undaria pinnatifida

A prized edible kelp — and one of the ocean’s most successful travellers

9 min read · Kelp & seaweeds

Golden fronds of giant kelp rising through sunlit blue water toward the surface canopy

Giant kelp

Macrocystis pyrifera

Foundation species — builds the towering forest canopy itself

8 min read · Kelp & seaweeds

Turkish towel

Chondracanthus exasperatus

A rough-skinned red of the low reef — a natural carrageenan carrier

7 min read · Kelp & seaweeds

Oarweed

Laminaria digitata

Habitat-former of the low-shore kelp zone; long harvested for alginates

9 min read · Kelp & seaweeds

Sugar kelp

Saccharina latissima

Fast-growing cold-water kelp; a workhorse species of northern kelp farming

9 min read · Kelp & seaweeds

Golden kelp

Ecklonia radiata

The dominant sub-canopy kelp of the Great Southern Reef and much of New Zealand

9 min read · Kelp & seaweeds

Sunbeams filtering through a bull kelp canopy in clear green water off a rocky Pacific coast, long stipes rising from the reef below.

Bull kelp

Nereocystis luetkeana

Annual canopy-former of exposed coasts; its hollow stipe floats fronds to the light

9 min read · Kelp & seaweeds

Invertebrates

Urchins, sea stars, abalone, lobsters and one very clever octopus — the grazers, predators and engineers of the reef floor.

120 profiles · View group →

Basket star

Gorgonocephalus eucnemis

The living net of the reef — unfolding a fractal tree of arms to catch drifting plankton

9 min read · Invertebrates

An orange-red bat star, its five webbed arms forming a soft pentagon, resting on coralline-encrusted rock beneath a sunlit kelp canopy.

Bat star

Patiria miniata

The reef’s clean-up crew: omnivore, scavenger and microbial-film polisher

8 min read · Invertebrates

Blacklip abalone

Haliotis rubra

Kelp-fed reef grazer behind one of the world’s most valuable wild shellfish fisheries

9 min read · Invertebrates

Blood star

Henricia leviuscula

A slow, smooth-skinned micro-predator and plankton-catcher of the lower reef

9 min read · Invertebrates

Blue-rayed limpet

Patella pellucida

Europe’s smallest kelp grazer, its shell shot through with living blue light

8 min read · Invertebrates

California mussel

Mytilus californianus

Ecosystem engineer of the surf zone — its beds shelter hundreds of smaller species

9 min read · Invertebrates

California spiny lobster

Panulirus interruptus

A night-time urchin predator whose foraging can tip the balance back toward kelp

8 min read · Invertebrates

Chestnut cowry

Neobernaya spadicea

A sponge-hunting snail whose presence — or absence — reads a reef’s health

8 min read · Invertebrates

Chilean kelp crab (jaiba marmola)

Taliepus dentatus

A kelp-bed omnivore and the target of one of Chile’s great working dive fisheries

9 min read · Invertebrates

Decorator crabs, the walking gardens

Spider crabs of the superfamily Majoidea

Crabs that dress in living algae and sponge — camouflage as a lifestyle

9 min read · Invertebrates

Flat abalone

Haliotis walallensis

The northernmost of California’s abalones — a low-profile grazer of drift algae

9 min read · Invertebrates

Flat porcelain crab

Petrolisthes cinctipes

The flattest filter-feeder on the shore — sweeping plankton past feathery mouthparts under the rocks

8 min read · Invertebrates

Frilled dogwinkle

Nucella lamellosa

A patient drilling predator of barnacles and mussels — and a living lesson in how form follows wave exposure

7 min read · Invertebrates

Giant keyhole limpet

Megathura crenulata

A mantle-cloaked grazer — and the source of keyhole limpet hemocyanin, a genuine medical tool

8 min read · Invertebrates

Giant red sea cucumber

Apostichopus californicus

The forest floor’s vacuum cleaner — eating and reworking the sediment kelp-fall leaves behind

9 min read · Invertebrates

Giant spined sea star

Pisaster giganteus

Edge-of-the-forest hunter with a taste for sand dollars

8 min read · Invertebrates

Pelagic goose barnacle

Lepas anatifera

The ocean’s castaway — a stalked filter-feeder riding drift lines to new shores

8 min read · Invertebrates

Graceful kelp crab

Pugettia gracilis

The small, slimmer twin of the kelp crab — an eelgrass-bed grazer and decorator in miniature

8 min read · Invertebrates

Green abalone

Haliotis fulgens

Shellfish of the kelp-forest edge — a drift-kelp grazer of southern reefs

9 min read · Invertebrates

Green-lipped mussel

Perna canaliculatus

New Zealand’s filter-feeding giant — wild reef builder and the backbone of a major aquaculture industry

8 min read · Invertebrates

Green sea urchin

Strongylocentrotus droebachiensis

The boreal grazer that built the northern barrens — and shows what balance means

9 min read · Invertebrates

Gumboot chiton, the armoured grazer

Cryptochiton stelleri

A night-shift grazer whose radula keeps coralline crusts scraped clean

9 min read · Invertebrates

Hairy shore crab

Hemigrapsus oregonensis

The quiet estuarine counterpart of the purple shore crab — a detritus-worker of mud and marsh

8 min read · Invertebrates

Hooded nudibranch

Melibe leonina

The canopy’s net-fishing slug — sweeping plankton from the drift with a living cast net

8 min read · Invertebrates

A Humboldt squid with crimson-flushed mantle glides through dark teal open water as faint light filters down from the surface.

Humboldt squid

Dosidicus gigas

A schooling jumbo squid and voracious midwater predator that shadows warm-water years

10 min read · Invertebrates

Kelp isopods, the frond pruners

Idotea, Pentidotea and other genera

The forest’s smallest gardeners — clipping fouling algae off the fronds, and in boom years chewing the stipes themselves

8 min read · Invertebrates

Kelp lace bryozoan

Membranipora membranacea

Harmless background texture in cool years — in warm, dense years a blade-shortening force

8 min read · Invertebrates

Spiny scallop

Chlamys hastata

A swimming filter feeder with a sponge bodyguard partnership and dozens of blue eyes

8 min read · Invertebrates

Leather star

Dermasterias imbricata

An anemone-eating sea star few of its prey can escape

7 min read · Invertebrates

Long-spined sea urchins clustered between rock crevices on a grazed pink-coralline reef, with golden kelp forest thinning in the sunlit background, Tasmania.

Long-spined sea urchin

Centrostephanus rodgersii

The range-shifting barren-builder rewriting Australia’s Great Southern Reef

9 min read · Invertebrates

Moon jelly

Aurelia aurita species complex

A gentle plankton-filterer whose occasional blooms crowd the water column

8 min read · Invertebrates

A moonglow anemone fully open in a sandy channel between dark rocks, its broad pale disc ringed with banded tentacles and its column buried in rippled, sunlit sand.

Moonglow anemone

Anthopleura artemisia

The buried anemone of the sand–rock seams — armour by gravel coat, preyed on by leather stars

8 min read · Invertebrates

A morning sun star with thirteen striped orange-grey arms grips a rock encrusted with pink coralline algae in a sunlit kelp forest.

Morning sun star

Solaster dawsoni

The specialist hunter of other sea stars — even the great sunflower star

8 min read · Invertebrates

Mossy chiton

Mopalia muscosa

A low-shore grazer whose shaggy girdle gardens its own coat of algae

7 min read · Invertebrates

Pinto (northern) abalone

Haliotis kamtschatkana

The small grazer of the understory; now rare across most of its range

10 min read · Invertebrates

Opalescent nudibranch

Hermissenda opalescens

The shimmer hunter — stealing stinging cells from hydroids and anemones to wear as its one defence

8 min read · Invertebrates

Orange sea pen

Ptilosarcus gurneyi

The feather anchored in sand — a suspension feeder whose colonies shelter small rockfish

7 min read · Invertebrates

Ostrich plume hydroid

Aglaophenia species

A stinging filter-feeding colony — and the hunting ground of specialist mites and sea slugs

8 min read · Invertebrates

A large oval owl limpet clinging to dark, algae-filmed rock in a Pacific tidepool, its worn shell ringed with growth lines in low natural light.

Owl limpet

Lottia gigantea

The territorial farmer of the mid-shore, guarding a personal algal lawn

9 min read · Invertebrates

Painted topshell

Calliostoma zizyphinum

A glossy, slow grazer of kelp-bed reefs — and a classic tidepooler’s find

8 min read · Invertebrates

A corrugated pink abalone clamped to kelp-edge rock in Baja California, drift kelp blades scattered across the reef around it.

Pink abalone

Haliotis corrugata

Kelp-edge grazer at the heart of Baja’s cooperative shellfish fishery

9 min read · Invertebrates

A giant rose-pink sea star glides over pale rippled sand at the foot of a bull kelp bed, sunbeams filtering through green water.

Giant pink sea star

Pisaster brevispinus

The soft-bottom giant of kelp country; itself prey for the returning sunflower star

8 min read · Invertebrates

Pinto abalone

Haliotis kamtschatkana

The northern abalone — a shallow grazer kept fed by drifting kelp

8 min read · Invertebrates

Plumose anemone

Metridium senile

The reef’s standing driftnet — a towering plankton mop that carpets cold-water walls

9 min read · Invertebrates

Purple-hinged rock scallop

Crassadoma gigantea

A filter feeder turned reef itself — its rugose shell shelters half a dozen smaller lives

8 min read · Invertebrates

Purple shore crab

Hemigrapsus nudus

A red-spotted scavenger linking the kelp canopy’s shed wrack to the tide line

8 min read · Invertebrates

Rainbow star

Orthasterias koehleri

The reef’s paintbox predator — eats snails, clams and even small urchins, one of the few sea stars that still takes grazers on

8 min read · Invertebrates

Red octopus — patchwork hunter

Octopus rubescens

The forest’s nocturnal landlord — den-puller, midden-keeper, evening hunt-master

8 min read · Invertebrates

Red rock crab

Cancer productus

The heavy hand at the kelp’s edge — a shell-crusher that helps keep urchins honest

9 min read · Invertebrates

Red sponge dorid

Rostanga pulchra

A thumbprint lesson in camouflage — lives, feeds and hides exactly on the red sponge it eats

8 min read · Invertebrates

Red turban snail

Chlorostoma funebralis

The reef’s lawn-mowing crew — whose population swings can tilt whole reefs

8 min read · Invertebrates

Eccentric sand dollar

Dendraster excentricus

An edge-standing suspension feeder crowding the sand beside the forest by the thousand

9 min read · Invertebrates

An underwater view of a kelp-bed boulder encrusted with a chalky colony of scaled worm snails, their ridged calcareous tubes layered across the rock beneath drifting kelp fronds.

Scaled worm snail

Thylacodes squamigerus

A reef-building snail that never moves — filter-feeding from a cemented tube

8 min read · Invertebrates

Sea lemon

Peltodoris nobilis

A citrus-scented sponge specialist of northern kelp beds

8 min read · Invertebrates

Sea lemon nudibranch

Peltodoris nobilis

A citrus-scented sponge specialist, told from its lookalikes by the gills

8 min read · Invertebrates

Sheep crab

Loxorhynchus grandis

The kelp floor’s armoured stroller — a scavenger whose mating piles are events in themselves

8 min read · Invertebrates

Green shore crab

Carcinus maenas

Europe’s toughest shore crab — and one of the world’s most consequential marine invaders

8 min read · Invertebrates

Six-rayed sea star

Leptasterias hexactis complex

A small brooding star that hatches its young under its own body

8 min read · Invertebrates

A Spanish shawl nudibranch — purple body, orange-red cerata and crimson rhinophores — crawling across a rocky reef beneath sunlit kelp fronds

Spanish shawl nudibranch

Flabellinopsis iodinea

The forest’s flame — an aeolid slug that steals stinging cells from hydroids and arms itself with them

8 min read · Invertebrates

Spanish shawl — where to find it

Flabellinopsis iodinea

The forest’s flame — sought by photographers, armed with stolen stings

8 min read · Invertebrates

Spot prawn

Pandalus platyceros

A hermaphrodite of the deep reef edge — and the pride of the Pacific trap fishery

9 min read · Invertebrates

Striped shore crab

Pachygrapsus crassipes

The bold green-striped sprinter of the rocks — grazer, scavenger and shorebird prey

8 min read · Invertebrates

Stubby rose anemone

Urticina coriacea

A stinging generalist predator of the forest floor, hunted in turn by leather stars

8 min read · Invertebrates

Two-spot octopus

Octopus bimaculoides

The kelp reef’s best-known den neighbour — shy by day, hunting on the night shift

8 min read · Invertebrates

Velvet swimming crab

Necora puber

The reef’s feistiest crab — paddle-legged hunter and quiet kelp-forest worker

8 min read · Invertebrates

Warty sea cucumber

Apostichopus parvimensis

The reef’s recycling line — turning shed kelp into pumpable seafloor

8 min read · Invertebrates

White abalone

Haliotis sorenseni

A deep-fringe grazer — now captive-bred and outplanted to rebuild the wild stock

8 min read · Invertebrates

White sea urchin

Lytechinus pictus

The sand-flat compost crew — a drift-kelp recycler, and a model organism of developmental biology

7 min read · Invertebrates

White-spotted rose anemone

Urticina lofotensis

The kelp forest’s signature wall anemone — scarlet with neat rows of white spots

8 min read · Invertebrates

Black abalone

Haliotis cracherodii

Intertidal grazer whose losses showed how fast a reef can unravel

8 min read · Invertebrates

Brittle stars

Ophiuroidea — many species

The forest floor’s most numerous residents — detritus processors and fish food

9 min read · Invertebrates

Dungeness crab

Metacarcinus magister

The kelp edge’s most famous crustacean — a roaming benthic predator at the heart of the West Coast crab fishery

8 min read · Invertebrates

Giant green anemone

Anthopleura xanthogrammica

A solar-powered predator — symbiotic algae tint a patient hunter of tidepool edges

8 min read · Invertebrates

Gumboot chiton

Cryptochiton stelleri

The “wandering meatloaf”: a magnetite-toothed grazer bulldozing algae from night-time rock

9 min read · Invertebrates

Northern kelp crab — forest pruner

Pugettia producta

A canopy-dwelling mesograzer that prunes the very fronds it lives on

8 min read · Invertebrates

Kelp forest nudibranchs

Nudibranchia — many species

Shell-less jewels that farm stinging cells and advertise in psychedelic colour

9 min read · Invertebrates

Norris’s top snail

Norrisia norrisi

A canopy grazer that lives its whole life on a giant kelp plant

9 min read · Invertebrates

Ochre sea star

Pisaster ochraceus

The original keystone species — remove it and the mussels take the shore

8 min read · Invertebrates

Orange-peel nudibranch

Tochuina tetraquetra

A hand-sized specialist predator of orange sea pens

7 min read · Invertebrates

Pāua

Haliotis iris

Grazer, taonga species and the jewel-shelled icon of New Zealand’s coast

8 min read · Invertebrates

Red abalone

Haliotis rufescens

Drift-kelp specialist that turns fallen fronds into reef life

8 min read · Invertebrates

Southern rock lobster

Jasus edwardsii

Urchin-hunting heavyweight — where big lobsters remain, barrens struggle to form

9 min read · Invertebrates

Stalked tunicates

Ascidiacea — many species

Chordate cousins filtering the understory — among our closest living invertebrate relatives

9 min read · Invertebrates

Strawberry anemone

Corynactis californica

A cloning carpet that turns bare rock into a reef in one colour

8 min read · Invertebrates

A large multi-armed sunflower sea star, golden orange with dozens of rays, spread across a rocky reef ledge in clear sunlit water

Sunflower sea star

Pycnopodia helianthoides

The forest’s fastest urchin predator — its loss freed urchins to swarm

9 min read · Invertebrates

Wavy turban snail

Megastraea undosa

The big, slow grazer of southern California’s reefs — with a small fishery of its own

8 min read · Invertebrates

Clown dorid

Triopha catalinae

A polka-dotted bryozoan grazer — one of the cold Pacific’s most unmistakable nudibranchs

8 min read · Invertebrates

Lacuna kelp snail

Lacuna vincta

A fingertip-sized blade grazer that trims the kelp it calls home

9 min read · Invertebrates

Market squid

Doryteuthis opalescens

The coast’s silver engine — prey for everything and one of California’s great fisheries

8 min read · Invertebrates

Mottled star

Evasterias troschelii

The “false” ochre star — a mollusc-hunting generalist that fills in where its keystone cousin is scarce

8 min read · Invertebrates

East Pacific red octopus

Octopus rubescens

The kelp forest’s small strategist — midden-keeper, crab-cracker, escape artist

8 min read · Invertebrates

Umbrella crab

Cryptolithodes sitchensis

A shape-shifting weed-crab of the canopy, hiding in plain sight

6 min read · Invertebrates

Fish-eating anemone

Urticina piscivora

The velvet trap beneath the kelp — a big red subtidal ambusher that takes small fish and shrimp

8 min read · Invertebrates

Northern kelp crab

Pugettia producta

Canopy-dwelling spider crab that grazes kelp by day and turns carnivore by night

7 min read · Invertebrates

Pacific tube anemone

Pachycerianthus fimbriatus

A stationary flower of the forest’s sandy floor, snagging drifting plankton

7 min read · Invertebrates

Giant red sea cucumber — the seafloor’s vacuum

Apostichopus californicus

A deposit-feeding recycler — the forest floor’s slow, indiscriminate vacuum

8 min read · Invertebrates

A dense carpet of small aggregating anemones with pink-tipped tentacles covering dark wet rock on a Pacific shore, split by a bare stripe between two clone colonies.

Aggregating anemone

Anthopleura elegantissima

The rocky shore’s clone army — space-holding carpet anemones fed by symbiotic algae and the swash zone

8 min read · Invertebrates

Kina

Evechinus chloroticus

New Zealand’s pasture-turning grazer; a prized kai moana delicacy

8 min read · Invertebrates

Painted anemone

Urticina crassicornis

The Christmas-anemone predator of kelp reefs, dressed in stuck-on shell and gravel

7 min read · Invertebrates

Purple sea urchin

Strongylocentrotus purpuratus

Keystone grazer — in hungry swarms it can fell entire forests

8 min read · Invertebrates

Red sea urchin

Mesocentrotus franciscanus

Large, long-lived grazer — barren-former, fishery target and forest regulator

8 min read · Invertebrates

A shag rug nudibranch, its back dense with grey finger-like cerata, gliding across a rock beside a small pink anemone in cold clear water.

Shag rug nudibranch

Aeolidia papillosa

Anemone hunter that farms its prey’s stinging cells into its own cerata for defence

8 min read · Invertebrates

Lion’s mane jellyfish

Cyanea capillata

Cold water’s drifting top predator of the plankton haze

8 min read · Invertebrates

Furry hermit crab

Paguristes ulreyi

Left-clawed reef-floor scavenger wearing a bristly setae coat and someone else’s shell

7 min read · Invertebrates

A giant Pacific octopus resting its brick-red arms around a rocky den beneath sunlit kelp fronds.

Giant Pacific octopus

Enteroctopus dofleini

Apex invertebrate of the reef — crab and shellfish predator of genius-level cunning

8 min read · Invertebrates

Moon jelly

Aurelia aurita

The ocean’s commonest jelly — plankton grazer and sea-turtle currency

8 min read · Invertebrates

Spiny sun star

Crossaster papposus

A many-armed opportunist of cold water, taking eggs, molluscs and urchins

8 min read · Invertebrates

California sea hare

Aplysia californica

A seaweed-grazing giant among sea slugs — and neuroscience’s favourite brain

8 min read · Invertebrates

A small brown kelp limpet seated in its home scar on a glossy feather boa kelp stipe, on wet wave-washed rock at low tide.

Kelp limpet

Discurria insessa

Obligate stipe-dweller — part gardener, part parasite of feather boa kelp, seated in a home scar for life

9 min read · Invertebrates

Ochre sea star

Pisaster ochraceus

The original “keystone species” — its mussel-eating holds shore diversity together

8 min read · Invertebrates

A small decorator crab wearing living red and brown algae stands camouflaged on a pink coralline rock ledge beneath a giant kelp canopy.

Sharpnose crab

Scyra acutifrons

The decorator that gardens its own back — planting algae on its shell until it vanishes into the understory

9 min read · Invertebrates

Leafy hornmouth

Ceratostoma foliatum

The winged snail of the kelp reef — a delicate-looking predator with a drill for a tongue

8 min read · Invertebrates

Heart crab

Phyllolithodes papillosus

A king-crab relative with a heart-shaped, armour-knobbed back — the reef’s living fossil

9 min read · Invertebrates

Blue-top snail

Calliostoma ligatum

The forest’s window cleaner — a top-shell that lives on kelp and polishes it blade by blade

8 min read · Invertebrates

Stalked jellyfish

Class Staurozoa (e.g. Haliclystus spp.)

Tiny anchoring ambush hunters that turn kelp blades into micro-reefs

10 min read · Invertebrates

Black tegula

Tegula funebralis

The long-lived grazer of the high shore — scraping microalgae where rock meets air for decades

8 min read · Invertebrates

Graceful rock crab

Metacarcinus gracilis

A fast-moving shell-crusher and scavenger of the bay floor

7 min read · Invertebrates

Helmet crab

Telmessus cheiragonus

A bristle-backed omnivore of eelgrass and kelp country, eaten eagerly by otters

7 min read · Invertebrates

A large sunflower sea star spreads its many arms across a rocky reef at the edge of a kelp forest, purple urchins grazing nearby in sunlit green water.

Sunflower sea star — the comeback case

Pycnopodia helianthoides

Once the forest’s chief urchin-eating patrol — its loss rewrote Pacific kelp history

11 min read · Invertebrates

Brooding anemone

Epiactis prolifera

A small predator that carries its young on its own skin until they are ready to walk

7 min read · Invertebrates

Fishes

Damselfish to draughtboard sharks, seadragons to sheephead — the residents of the mid-water jungle between canopy and floor.

132 profiles · View group →

Atlantic wolffish

Anarhichas lupus

The reef’s shell-crusher — a slow predator of urchins and crabs that keeps grazers honest

10 min read · Fishes

Ballan wrasse

Labrus bergylta

Europe’s kelp-rock foreman — nest-builder, sex-changer, shell-crusher and farmed cleaner-fish

9 min read · Fishes

Banded morwong

Cheilodactylus spectabilis

The site-attached elder of the reef — a benthic picker whose long life makes it a sensitive fishing indicator

8 min read · Fishes

Bat ray

Myliobatis californica

A shell-crushing forager whose feeding pits till the seafloor beside the reef

8 min read · Fishes

Big skate

Beringraja binoculata

The flat giant of the sand margin — mother of the biggest mermaid’s purses on the coast

9 min read · Fishes

Black-and-yellow rockfish

Sebastes chrysomelas

The stay-at-home of the kelp bed — a boldly barred rockfish defending its patch of reef for a decade or more

9 min read · Fishes

Black croaker

Cheilotrema saturnum

The kelp bed’s night drummer — a drumming sciaenid that feeds on invertebrates over the reef after dark

8 min read · Fishes

Black-eyed goby

Coryphopterus nicholsii

A hovering plankton-picker that holds station over the kelp floor in loose schools

8 min read · Fishes

Black rockfish

Sebastes melanops

The schooling shadow over the canopy — a midwater hunter of krill and baitfish above the reef

7 min read · Fishes

Black surfperch

Embiotoca jacksoni

The kelp bed’s plodding picnicker — a live-bearing browser that picks small life from the fronds

7 min read · Fishes

Black-and-yellow rockfish

Sebastes chrysomelas

The jewel of the shallow rocks — a bold-patterned ambush predator that rarely leaves home

7 min read · Fishes

Blackeye goby

Rhinogobiops nicholsii

The drifting guard posts of the kelp bed — plankton catchers whose density reads as reef health

7 min read · Fishes

Blacksmith

Chromis punctipinnis

The charcoal damselfish whose dense schools crop the canopy’s passing plankton

8 min read · Fishes

Brown rockfish

Sebastes auriculatus

The shallowest of the rockfish — a dusky, harbour-tolerant homebody of kelp country

7 min read · Fishes

Butterfish (rock gunnel)

Pholis gunnellus

A sneaky, eel-like shore fish wearing a necklace of eyespots down its back

8 min read · Fishes

Cabezon

Scorpaenichthys marmoratus

The grumpy egg-guarding ambusher of the reef floor

8 min read · Fishes

A California flying fish glides just above a calm dawn sea with both pairs of dark wing-like fins spread, a faint spray trail behind its tail, a kelp-covered headland on the horizon.

California flying fish

Cheilopogon pinnatibarbatus californicus

A warm-season glider whose comings and goings read like a calendar of the kelp coast

9 min read · Fishes

California halibut

Paralichthys californicus

An ambush flatfish rising off the sand to take anchovies and smelt

9 min read · Fishes

A bright orange canary rockfish hovering above a dark rocky reef in deep blue-green Pacific water, sunbeams falling from the surface

Canary rockfish

Sebastes pinniger

A long-lived deep-reef rockfish whose crash and rebuild became the west coast’s model fisheries story

9 min read · Fishes

China rockfish

Sebastes nebulosus

A crevice-hugging rockfish that keeps its life local — a long-lived measure of reef quality

8 min read · Fishes

Copper rockfish

Sebastes caurinus

A long-lived reef resident that needs structure — kelp — to hide and hunt

8 min read · Fishes

Corkwing wrasse

Symphodus melops

Nest-building cleanerfish of Europe’s kelp — now fished at scale for salmon farms

9 min read · Fishes

Giant kelpfish

Heterostichus rostratus

The shape-shifting ambusher — shifting reds, browns and greens to vanish against the fronds it hunts from

7 min read · Fishes

Goldsinny wrasse

Ctenolabrus rupestris

The Atlantic kelp bed’s most abundant small wrasse — parasite cleaner and salmon-farm conscript

8 min read · Fishes

Gopher rockfish

Sebastes carnatus

The quiet reef homebody — a long-lived ambusher ageing gently in the kelp bed’s shadows

7 min read · Fishes

Grass rockfish

Sebastes rastrelliger

A stealth hunter of crabs and small fish, woven through the kelp-bed floor

8 min read · Fishes

Great sculpin

Myoxocephalus polyacanthocephalus

The big-headed floor boss of the reef edge, a bottom-hugging ambusher of crabs and small fishes

8 min read · Fishes

Grunt sculpin

Rhamphocottus richardsonii

A walking-finned ambusher that poses as a living barnacle

7 min read · Fishes

A school of slate blue-grey halfmoon fish with crescent tails cruising beneath a golden kelp canopy in sunlit Southern California water.

Halfmoon

Medialuna californiensis

The dusk school — a small-mouthed grazer that filters the kelp edge for bits of everything

8 min read · Fishes

A horn shark resting on a rocky kelp-forest floor at night, lit by a diver's torch, with purple sea urchins nearby

Horn shark

Heterodontus francisci

The kelp bed’s night specialist — crushing urchins until its teeth stain purple

8 min read · Fishes

Kelp greenling

Hexagrammos decagrammus

An ambush predator whose sexes look like different species

8 min read · Fishes

Kelp perch

Brachyistius frenatus

The canopy’s resident browser — a live-bearing surfperch that lives among the fronds themselves

9 min read · Fishes

Kelp rockfish

Sebastes atrovirens

A canopy specialist that lives its life between the blades

7 min read · Fishes

Lumpsucker (lumpfish)

Cyclopterus lumpus

The suction-cup reef clown — and a working cleaner fish in salmon aquaculture

9 min read · Fishes

Marblefish

Aplodactylus arctidens

The odd surgeon of the southern kelp — a true herbivore that crops the forest itself

7 min read · Fishes

Monkeyface prickleback

Cebidichthys violaceus

The rare fish herbivore — grazing seaweed at the water’s edge and breathing the tide out

8 min read · Fishes

Northern anchovy

Engraulis mordax

A plankton-straining forage school that fuels salmon, seabirds and sea lions

9 min read · Fishes

Olive rockfish

Sebastes serranoides

A schooling mid-water hunter threading the kelp canopy

9 min read · Fishes

Opaleye

Girella nigricans

The blue-eyed grazer of the shallow kelp — the fish that eats where the waves break

8 min read · Fishes

Ornate cowfish

Aracana ornata

A benthic sifter of small invertebrates; males wear dazzling blue-and-orange pinstripes

8 min read · Fishes

A school of silvery Pacific barracuda holding station in sunlit green water just off the edge of a towering giant kelp forest, with god rays slanting down through the canopy.

Pacific barracuda

Sphyraena argentea

The kelp edge’s silver pursuit predator, hunting baitfish in loose schools

9 min read · Fishes

Pacific bonito

Sarda chiliensis

The silver comet beyond the canopy — a small tuna whose visits mark warm water on kelp coasts

8 min read · Fishes

Pacific hagfish

Eptatretus stoutii

The deep-sea cleaner of the kelp coast — a slime-weaving scavenger that turns carrion falls back into the system

8 min read · Fishes

Pacific herring

Clupea pallasii

The kelp coast’s keystone forage fish — its spawn can whiten kilometres of shoreline

9 min read · Fishes

Pacific lamprey

Entosphenus tridentatus

A jawless, ancient traveller ferrying ocean nutrients from the kelp coast into headwater rivers

9 min read · Fishes

Pacific sand lance

Ammodytes personatus

The buried forage fish — the linchpin prey that carries the kelp edge’s energy to salmon, seabirds and whales

8 min read · Fishes

Pacific sardine

Sardinops sagax

A boom-and-bust forage river — the silver school behind Cannery Row’s rise and collapse

10 min read · Fishes

Pacific spiny lumpsucker

Eumicrotremus orbis

The roundest resident of the bed — a finless-looking drifter that anchors itself to a leaf and waits

7 min read · Fishes

Painted greenling

Oxylebius pictus

A small perched ambush fish of the reef floor and low canopy

7 min read · Fishes

Pile perch

Rhacochilus vacca

A striped surfperch browsing the mid-water jungle between canopy and pier

7 min read · Fishes

A large golden pot-bellied seahorse with a deep, rounded belly curves among kelp fronds in green subtidal water, natural light filtering down

Pot-bellied seahorse

Hippocampus abdominalis

A holdfast-hitching ambusher of swarming tiny crustaceans

8 min read · Fishes

Quillback rockfish

Sebastes maliger

The patient kelp-reef bass — a solitary, long-lived ambusher loyal to one piece of reef

8 min read · Fishes

A rainbow seaperch in orange-red and blue striping hovers among sunlit kelp fronds.

Rainbow seaperch

Hypsurus caryi

The coral-coloured surfperch of cold water — a live-bearing kelp-forest picker

7 min read · Fishes

Red Irish lord

Hemilepidotus hemilepidotus

A bottom-glued sculpin that waits for almost anything it can engulf

8 min read · Fishes

Rock wrasse

Halichoeres semicinctus

A sex-changing kelp-reef wrasse whose juveniles run cleaner stations

8 min read · Fishes

Rosy rockfish

Sebastes rosaceus

The reef’s quick blush of red — a mid-sized rockfish drifting the kelp margins

8 min read · Fishes

Rubberlip seaperch

Rhacochilus toxotes

A thick-lipped invertebrate-picker working the reef edge in surge

8 min read · Fishes

Saddleback gunnel

Pholis ornata

The eel-lookalike of the kelp fringe, wearing a row of dark saddle blotches down its back

9 min read · Fishes

Saithe (coalfish)

Pollachius virens

The dark gadoid that grows up inside the kelp before joining the open-water hunt

8 min read · Fishes

Sarcastic fringehead

Neoclinus blanchardi

The mouth-first homemaker — gape-wrestling rivals for territory on the reef’s fringe

7 min read · Fishes

Shiner surfperch

Cymatogaster aggregata

The silver cloud in the canopy — a forage fish that carries kelp-bed productivity to bigger mouths

7 min read · Fishes

A shovelnose guitarfish glides over a sand channel between low kelp-forest reef in sunlit green water

Shovelnose guitarfish

Pseudobatos productus

The bottom-grazing flat-rajid of the kelp coast’s sandy lanes

9 min read · Fishes

A bluntnose sixgill shark with pale green eyes cruising at dusk along a steep rock wall, with the dim silhouettes of a kelp forest rising toward faint light behind it

Bluntnose sixgill shark

Hexanchus griseus

The deep giant that visits kelp country — a primitive sixgilled shark on a nightly commute up from the dark

9 min read · Fishes

Soupfin shark (tope)

Galeorhinus galeus

The kelp coast’s ill-fated voyager — once fished near collapse for liver vitamin A

8 min read · Fishes

Speckled sanddab

Citharichthys stigmaeus

A small ambusher of worms and crustaceans, speckled into invisibility against the sand

8 min read · Fishes

A tiny Pacific spiny lumpsucker — a round, cone-studded olive-green fish — clamped by its suction-disc belly to an eelgrass blade, with soft-focus kelp and sunbeams behind

Pacific spiny lumpsucker

Eumicrotremus orbis

A suction-cupped grazer of tiny crustaceans; males guard the egg cluster

7 min read · Fishes

Spotted ratfish

Hydrolagus colliei

The kelp coast’s ghost shark — a living chimaera gliding through on wings of pectoral fin

10 min read · Fishes

Staghorn sculpin

Leptocottus armatus

The antler-spined hunter of tidal creeks — venomous cheek spines, and a staple of herons and larger fish in the soft shallows

8 min read · Fishes

Striped seaperch

Embiotoca lateralis

A live-bearing picker that winnows crustaceans from the understory

9 min read · Fishes

Striped seaperch

Embiotoca lateralis

The neon stripe at the kelp’s edge — a live-bearing browser picking small life from rock and frond

8 min read · Fishes

Swell shark

Cephaloscyllium ventriosum

The inflatable night shark — asleep in the kelp by day, ballooning into a locked wedge when threatened

8 min read · Fishes

Kelp perch

Brachyistius frenatus

A live-bearing surfperch that sips plankton and picks parasites off larger fish

8 min read · Fishes

Treefish

Sebastes serriceps

The reef’s small gold sentinel — guarding crevices and biting anything rude

7 min read · Fishes

Vermilion rockfish

Sebastes miniatus

A long-lived predator holding the reef edge where canopy meets open water

8 min read · Fishes

White seabass

Atractoscion nobilis

The ghost of the kelp forest — a croaker that cruises the fringes after surfperch and squid

10 min read · Fishes

A large orange-red yelloweye rockfish with a bright yellow eye hovering above a sponge-encrusted rocky reef, with the kelp canopy dim overhead

Yelloweye rockfish

Sebastes ruberrimus

The long-lived orange elder of the deep reef — a fish gone for generations wherever it is fished away

9 min read · Fishes

Blue rockfish

Sebastes mystinus

The schooling plankton-picker that makes the canopy shimmer — and a fishery mainstay

8 min read · Fishes

Bluebanded goby

Lythrypnus dalli

A sex-changing micro-predator and the reef’s most dazzling small resident

8 min read · Fishes

Broadnose sevengill shark

Notorynchus cepedianus

An ancient apex cruiser built on a body plan older than most reefs it patrols

9 min read · Fishes

Garibaldi

Hypsypops rubicundus

Territorial gardener of algal nests; California’s protected state marine fish

7 min read · Fishes

Leopard shark

Triakis semifasciata

A harmless invertebrate-hunting houndshark famous for its summer aggregations

8 min read · Fishes

Lingcod

Ophiodon elongatus

Not a cod at all — the kelp reef’s nest-guarding ambush predator (with famously blue flesh)

9 min read · Fishes

Tiger rockfish

Sebastes nigrocinctus

A long-lived banded hermit of the deep reef edge

7 min read · Fishes

Wolf eel

Anarrhichthys ocellatus

Not an eel at all — a devoted, urchin-crushing den-dweller that guards eggs for months

9 min read · Fishes

California moray

Gymnothorax mordax

The reef’s most patient hunter — a crevice ambusher of octopus, fish and crabs

7 min read · Fishes

Coralline sculpin

Artedius corallinus

The invisible gardener of the pink reef — picking small crustaceans from the coralline crusts

7 min read · Fishes

Eastern blue groper

Achoerodus viridis

Charismatic urchin and crab hunter; the fish emblem of New South Wales

8 min read · Fishes

Giant black sea bass — the comeback

Stereolepis gigas

The kelp forest’s giant resident predator, mid-recovery after a fishing-era crash

8 min read · Fishes

Pacific electric ray

Tetronarce californica

A sluggish ambush predator that stuns fast fish with a 50-volt discharge

8 min read · Fishes

Rockweed gunnel

Xererpes fucorum

A crimson fish that vanishes into red weed a shade away

6 min read · Fishes

Spotted kelpfish

Gibbonsia elegans

A shape-shifting clinid whose colour morphs match red, green and brown kelp backgrounds

7 min read · Fishes

A weedy seadragon drifting among golden kelp fronds in sunlit green water off southern Australia

Weedy seadragon

Phyllopteryx taeniolatus

Seahorse relative that vanishes into kelp; males carry the eggs on their tails

7 min read · Fishes

Blue-banded goby

Lythrypnus dalli

A micro-predator of the reef floor that changes sex with its social rank

8 min read · Fishes

Kelp bass

Paralabrax clathratus

Ambush predator of the canopy itself — “calico bass” to generations of anglers

8 min read · Fishes

Kelp snailfish

Liparis mucosus

The storm-proof-basement tenant of the holdfast maze — inconspicuous, essential, everywhere

7 min read · Fishes

Leafy seadragon

Phycodurus eques

Mimicry made flesh — an ambush plankton-hunter disguised as drifting weed

7 min read · Fishes

A masked greenling — olive-brown with dark flank bars and a dark stripe through its eye — perched on a kelp-covered rock in cold green Alaskan shallows.

Masked greenling

Hexagrammos octogrammus

A cold-water ambusher of the northern kelp beds, watching from the rocks

9 min read · Fishes

Reef surfperch

Micrometrus aurora

A small livebearing surfperch working the noisy seam between canopy and surf zone

7 min read · Fishes

A buffalo sculpin rests on a rock ledge in a north Pacific kelp bed, its broad spiny head and mottled camouflage blending with the encrusted reef beneath green-gold kelp fronds.

Buffalo sculpin

Enophrys bison

The horned ambusher of the kelp understory — venom-bearing spines and a mouthful of crab

8 min read · Fishes

California sheephead

Semicossyphus pulcher

Urchin-crunching wrasse — a predator the forest badly wants back

8 min read · Fishes

Northern clingfish

Gobiesox maeandricus

A living suction cup — its fused-fin disc outgrips engineered cups on rough wet rock

7 min read · Fishes

Port Jackson shark

Heterodontus portusjacksoni

Nocturnal urchin-eater whose migratory egg-laying cities dot southern reefs

8 min read · Fishes

Starry flounder

Platichthys stellatus

The flatfish that walks between river and reef, ambushing crabs on the sand

8 min read · Fishes

Giant sea bass

Stereolepis gigas

The kelp forest’s biggest resident predator, returning from the brink

8 min read · Fishes

A giant sea bass hangs motionless in green sunlit water beneath a giant kelp canopy off California, vertical shafts of light falling through the fronds onto its dark, blotched flank.

Giant sea bass

Stereolepis gigas

The gentle giant of the kelp forest — a curious, slow-moving top predator of croakers, lobsters and squid

8 min read · Fishes

Tubesnout

Aulorhynchus flavidus

A canopy-edge forage school that fastens its eggs to kelp stipes

9 min read · Fishes

Woolly sculpin

Clinocottus analis

The tidepool’s endurance champion — an air-breathing sculpin that can sit out of water for hours

7 min read · Fishes

Crescent gunnel

Pholis laeta

A ribbon-thin resident of the kelp fringe, named for the crescent mark above its eye

9 min read · Fishes

Señorita

Oxyjulis californica

The kelp forest’s cleaner wrasse — hygienist by day, sand-sleeper by night

8 min read · Fishes

Plainfin midshipman

Porichthys notatus

The singing toadfish of the kelp coast — males hum all night to court

8 min read · Fishes

A bay pipefish holding vertical among green eelgrass blades in sunlit water, camouflaged to match the swaying vegetation.

Bay pipefish

Syngnathus leptorhynchus

A grass-blade mimic that snipes tiny crustaceans with a snort of suction

9 min read · Fishes

Walleye surfperch

Hyperprosopon argenteum

The silver flash in the kelp surge — a live-bearing perch that feeds at the canopy margin

7 min read · Fishes

High cockscomb

Anoplarchus purpurescens

An intertidal omnivore with devoted fathers — males coil around and guard the eggs

9 min read · Fishes

Rainbow surfperch

Hypsurus caryi

The most colourful surfperch on the coast — bars, dots and stripes at the kelp-bed edge

7 min read · Fishes

Pacific herring

Clupea pallasii

The forage engine that turns plankton into a coast-wide feast — on kelp as a nursery

10 min read · Fishes

Sailfin sculpin

Nautichthys oculofasciatus

A flag-finned sculpin flashing warnings and courtship at the reef edge

8 min read · Fishes

Crevice kelpfish

Gibbonsia montereyensis

The colour-matching ghost of the understory — shifting red, brown or olive to match the weed it hides in

7 min read · Fishes

Mosshead warbonnet

Chirolophis nugator

A crevice-wedging ambusher of small crustaceans, dressed in camouflage fronds

8 min read · Fishes

Penpoint gunnel

Apodichthys flavidus

A weed-matched eel-lookalike that can weather hours out of water

11 min read · Fishes

Scalyhead sculpin

Artedius harringtoni

A small cryptic sculpin whose “headwear” breaks up its outline against the reef

8 min read · Fishes

Whitespotted greenling

Hexagrammos stelleri

A changeable ambusher of the rocky reef, in two distinct colour coats

12 min read · Fishes

Brown Irish lord

Hemilepidotus spinosus

A cold-water sculpin picking small crustaceans and fish off the reef

8 min read · Fishes

Ocean sunfish

Mola mola

A gelatinous-zooplankton hunter that visits kelp reefs for cleaning services

9 min read · Fishes

Kelp greenling, the egg guardian

Hexagrammos decagrammus

A deep-dive look at the greenling’s double life — and the fathers who guard the eggs

9 min read · Fishes

California scorpionfish

Scorpaena guttata

The venomous stone in the kelp’s shadow — an ambush predator that rewards slow eyes

8 min read · Fishes

Greenbone (butterfish)

Odax pullus

New Zealand’s kelp-shearing herbivore — a grazer whose feeding keeps algal turf in check

7 min read · Fishes

Yellowtail rockfish

Sebastes flavidus

The nomad school at the kelp edge — a roaming plankton eater that links the open ocean to the reef

8 min read · Fishes

Striped trumpeter

Latris lineata

Tasmania’s deep-reef druid — a long-lived kelp-edge fish beloved of the craypot fishery

8 min read · Fishes

Herring cale

Odax cyanomelas

A true kelp-eater of the Great Southern Reef — one of the few fish that digests the canopy directly

7 min read · Fishes

Tidepool sculpin

Oligocottus maculosus

A tidepool survivor built for heat, salt spikes and hours of air

8 min read · Fishes

A large deep-blue western blue groper patrolling beside a kelp-draped granite ledge in green Australian water, sunbeams filtering through the canopy.

Western blue groper

Achoerodus gouldii

The south-west’s blue emperor — a slow, decades-old kelp reef matriarch-patriarch of the reef

8 min read · Fishes

Pacific angel shark

Squatina californica

A flat-bodied ambusher hidden in sand at the kelp edge

8 min read · Fishes

Seabirds

The life above the canopy — oystercatchers, auks and gulls that read the water and nest the coast.

14 profiles · View group →

Australasian gannet

Morus serrator

The arrow of the southern coast — a plunge-diver that thumps baitfish over the kelp line

7 min read · Seabirds

Common murre

Uria aalge

The flying penguin of northern seas — a wing-powered pursuit diver riding forage-fish schools

10 min read · Seabirds

Harlequin duck

Histrionicus histrionicus

The painted bird of the surf zone — picking snails, crabs and larvae from the kelp edge between the waves

7 min read · Seabirds

Humboldt penguin

Spheniscus humboldti

The upwelling coast’s penguin — a warm-latitude hunter of the kelp-rich Humboldt

8 min read · Seabirds

Kelp gull

Larus dominicanus

The southern hemisphere’s coastal generalist — a flexible hunter-scavenger above every kelp coast it meets

8 min read · Seabirds

Little penguin

Eudyptula minor

The blue fairy of the kelp coast — home-grown, burrow-nesting and working the inshore frontier

7 min read · Seabirds

Rhinoceros auklet

Cerorhinca monocerata

The kelp coast’s burrowing auklet — a purse-seiner of the surface shoals that flies home after dark

7 min read · Seabirds

Black oystercatcher

Haematopus bachmani

The rocky shore’s sentinel — piping over the place where kelp meets beach

8 min read · Seabirds

Black oystercatcher

Haematopus bachmani

The resident sentinel of rich rocky shores, piping alarm at anything that moves

7 min read · Seabirds

A raft of common eiders on calm grey water at the edge of a kelp-fringed northern rocky coast, a black-and-white drake beside a barred brown hen in morning mist.

Common eider

Somateria mollissima

The heavy-bodied sea duck that crushes shellfish whole and gave its name to eiderdown

8 min read · Seabirds

Marbled murrelet

Brachyramphus marmoratus

A seabird with its life split between two vanishing worlds — the kelp sea and the ancient forest

7 min read · Seabirds

Pelagic cormorant

Urile pelagicus

The slim diver of the outer kelp line, picking fish from the reef’s shadowed faces

8 min read · Seabirds

Pigeon guillemot

Cepphus columba

A red-footed diver ferrying single rockfish to its seaside nest

8 min read · Seabirds

Tufted puffin

Fratercula cirrhata

The kelp coast’s most photogenic fisher, feeding chicks from the baitfish schools

8 min read · Seabirds

Marine mammals

Otters, seals and sea lions — the warm-blooded citizens of cold water, including the kelp forest’s most famous keystone.

17 profiles · View group →

Australian fur seal

Arctocephalus pusillus doriferus

The Bass Strait’s big hunter — a shelf predator that loafs and plays in surface kelp rafts

10 min read · Marine mammals

Dall's porpoise

Phocoenoides dalli

The fastest small cetacean in kelp waters — the coast’s black-and-white express

9 min read · Marine mammals

Gray whale

Eschrichtius robustus

A bottom-feeding baleen whale whose migration follows the kelp coast for thousands of kilometres

9 min read · Marine mammals

Gray whale

Eschrichtius robustus

The sentinel of the coastal migration — feeding, rubbing and hiding calves in the kelp line

9 min read · Marine mammals

Harbour seal at the kelp edge

Phoca vitulina

Not a kelp resident, but a kelp neighbour — the seal–forest relationship, unpacked

8 min read · Marine mammals

Northern fur seal

Callorhinus ursinus

The oceanic eared seal with the thickest fur in the sea — harvesting the open water beyond the kelp

7 min read · Marine mammals

New Zealand sea lion (rāpoka)

Phocarctos hookeri

The rarest sea lion in the surf — a deep-diving endemic whose mainland comeback is a rare good-news trend

9 min read · Marine mammals

South American sea lion

Otaria byronia

The port-city lion of two oceans — a sweeping coastal predator of the Humboldt and Patagonian kelp

10 min read · Marine mammals

A southern right whale resting at the surface beside a raft of giant kelp in calm, sunlit southern water

Southern right whale

Eubalaena australis

The whale that plays in kelp — slow coastal giants that ride, rub and sail with the fronds

10 min read · Marine mammals

Steller sea lion

Eumetopias jubatus

A tonne of muscle above the kelp line — the sea lion that anchors the northern food web

10 min read · Marine mammals

California sea lion

Zalophus californianus

The acrobat of the kelp forest — fast, social and endlessly inquisitive

8 min read · Marine mammals

Harbour seal

Phoca vitulina

The kelp coast’s commonest pinniped — fish-hunter and curious escort of divers

8 min read · Marine mammals

New Zealand fur seal

Arctocephalus forsteri

A sealing-era survivor now recolonising its old kelp-forest shores

8 min read · Marine mammals

Harbour porpoise

Phocoena phocoena

The unobtrusive neighbour of nearshore kelp — an anchor species for coastal citizen science

8 min read · Marine mammals

A sea otter floating on its back among sunlit giant kelp canopy, holding a sea urchin in its forepaws

Sea otter

Enhydra lutris

The keystone: eats urchins, lets forests stand

8 min read · Marine mammals

Pacific white-sided dolphin

Lagenorhynchus obliquidens

An acrobatic schooler of cold North Pacific waters, herding baitfish inshore

8 min read · Marine mammals

Northern elephant seal

Mirounga angustirostris

The coast’s deep-diving heavyweight, resting on the surface between long hunts

9 min read · Marine mammals

Where they live

Trace these species through the Coastal Atlas — the reefs, bays and headlands where the forest stands.

Open the atlas →

How the forest works

The physics and biology underneath: upwelling, trophic cascades, the kelp life cycle and more.

Read the science →

How we count them

Canopy Ledger turns drones, satellites and dive surveys into verified biodiversity records.

See Canopy Ledger →

A species you love isn’t here yet?

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