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Species
Algae
Identifying algae is not always easy! Learn more about the algae monitored by the LiMPETS program. The list below includes:
- 16 core taxa that are monitored at as many sites as possible
- 3 other taxa (denoted with *) that are monitored at only one or two sites
Go to Datasheets and Forms to find out which species are monitored at your LiMPETS site of interest.
- Dead man’s fingers – Codium fragile
- Encrusting coralline algae – Many species
- Feather boa kelp – Egregia menziesii
- Flattened rockweeds – Fucus spp./Hesperophycus californicus
- Green pin-cushion alga – Cladophora columbiana
- Iridescent algae – Mazzaella flaccida/splendens
- Lawn alga – Chondracanthus canaliculatus
- Nori – Porphyra spp.
- Scouring-pad alga – Endocladia muricata
- Sea lettuces – Ulva spp.
- Sea sacs – Halosaccion glandiforme
- Slender rockweeds – Pelvetiopsis limitata/Silvetia compressa
- Stunted turkish towel – Mastocarpus spp./Mazzaella affinis
- Surfgrasses – Phyllospadix scouleri/torreyi
- Tar spot algae – Mastocarpus spp./Ralfsia spp. and others
- Upright coralline algae – Bossiella spp./Calliarthon spp./Corallina spp.
- * Christmas card algae – Microcladia spp./Plocamium spp.
- * Frilly red algae – Cryptopleura spp.
- * Vermicelli alga – Gracilariopsis lemaneiformis
- We also monitor:
- Bare rock
- Loose sand
- Tar (petroleum)
Flattened Rockweeds (Fucus spp./Hesperophycus californicus)
- Description:
- Flattened rockweeds are an olive green to dark brown color. They can reach 25-30 cm (1 foot) in length; have a small holdfast and flattened, dichotomously branched blades with a distinct midrib. Flattened rockweeds have a thick outside layer that makes a sticky substance to help retain moisture.
- Distribution:
- British Columbia to central Baja California.
- Habitat:
- Common in the mid-high intertidal zone in areas with moderate to heavy waves.
- Diet:
- Sunlight and dissolved nutrients, which are required for photosynthesis.
- Fun Fact:
- To discourage predation, rockweeds secrete a chemical that makes them hard to digest.
- Reason for Monitoring:
- Flattened rockweeds have a relatively large body and small holdfast, making them sensitive to human trampling. When individuals are stepped on, the increased strain can easily dislodge the holdfast. Their disappearance is a good indication that too much trampling has occurred.
- References:
- Encyclopedia of the Sanctuary
- Jenkins et al. 2001. Watch Your Step: Impacts of Trampling on a Rocky Shoreline of San Juan Island, Washington.
- Mondragon, J and J. Mondragon. 2003. Seaweeds of the Pacific Coast: Common Marine Algae from Alaska to Baja California. Sea Challengers, Monterey,California.