Stats

Lifespan: 3-5 yrs
Size: Medium
Diet: Photosynthetic
Biome: Rocky intertidal
Range: Northern Hemisphere
Movement: Sessile
Breeding: Spores
Defense: Toxins
Status: Common

About

Rockweed is a rubbery brown seaweed that clings to rocky intertidal shores, its flattened, forked fronds lined with air-filled bladders that keep it buoyant at high tide. It can survive hours of air exposure between tides by sealing moisture inside its thick, leathery thallus.

Life cycle

1.
spore
A microscopic zoospore drifts on the current and settles onto bare rock to take hold.
2.
young blade
A holdfast grips the seafloor as the first blade unfurls and reaches toward the sunlit surface.
3.
mature kelp
Fully grown — a towering frond buoyed by gas bladders, swaying in the kelp-forest canopy.

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Taxonomy

Kingdom: Chromista
Phylum: Ochrophyta
Class: Phaeophyceae
Order: Fucales
Family: Fucaceae
Genus: Fucus
Species: Fucus distichus