Brown Algae
Click on the images to learn more about two iconic brown seaweeds of British Columbia
Alaria marginata
Winged kelp
The kelp Alaria marginata (common names: winged kelp or ribbon kelp) has a body consisting of a single long blade with a thickened middle region called a "midrib". The blade is connected to a branched holdfast by a short, cylindrical stipe. When reproductive, Alaria produces several smaller side blades below the main blade; these side blades are sometimes wing-shaped and are the inspiration for the common name. Alaria marginata grows on rock in the mid to low intertidal zone and is an annual species, meaning the seaweed grows and dies within a single season. This species is common in British Columbia in exposed to semi wave-protected habitats. Click the icons above for more images, a life cycle and a peak inside the Beaty Biodiversity Museum’s collections of this species.
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Nereocystis luetkeana
Bull kelp
The kelp Nereocystis luetkeana (common names: Bull Kelp, Bullwhip Kelp, Sea Otter’s Cabbage) is probably the most recognizable seaweed of the Northeast Pacific. As one of only two canopy-forming kelp species in British Columbia (the other being the Giant Kelp), Nereocystis creates many of the large underwater forests along our coast. The body of Nereocystis consists of a branched, root-like holdfast, a very long, rope-like stipe, a single gas-filled float and many long, thin, leaf-like blades. Nereocystis is an annual species, meaning the seaweed grows and dies within a single season (~March to October). Remarkably, this species is also one of the largest seaweeds in the world, reaching lengths of 30m or more. To achieve these great lengths in a short time, Nereocystis grows swiftly, with the blades observed growing up to 15cm per day. Nereocystis luetkeana grows on rock and is a subtidal species, though juveniles can often be found growing in the low and even mid-intertidal in the early spring. This species is common in British Columbia in high-current or semi wave-exposed habitats. The genus name Nereocystis (NEAR-ee-o-SYST-is) comes from the Greek words Nereis (a daughter of the ancient sea god Nereus) and kystis (a bladder or float). The species name luetkeana (lewt-KEY-ah-na) is named in honor of Captain Freidrich Benjamin von Lütke. Captain Lütke lead a Russian exploration of the Pacific Coast of North America from 1826-1829; it was during this exploration that specimens of Nereocystis were documented by European naturalists for the first time. Click the icons above for more images, a life cycle and a peak inside the Beaty Biodiversity Museum’s collections of this species.