Pacific Oyster
Crassostrea gigas
Description: This large oyster (to ~30cm long) has grey or white shells, with purple or black new growth. Shells are generally irregular in shape with fluted exterior edges, lower cup shaped shell is larger than the top. Pacific Oyster lives to 20 years, but is harvested commercially at 2-4 years. Edible and delicious, requires license and awareness of red tides and bag limits when collecting your own.
Ecology: A very common mollusk introduced to BC ad Washington state in 1922 from Japan. Found in intertidal zones to depths of 6m.
Notes: These ones were found on the beach at low tide in a sheltered bay in Sechelt Inlet, summer 2001.
Black Katy Chiton
Katharina tunicata
Description: A large chiton growing up to 12cm long with a brown or black girdle that covers most of the chiton with a white diamond shape left uncovered on the top of each valve.
Ecology: Found on exposed rocky shorelines in the mid intertidal zone throughout coastal BC.
Notes: This one was found with a bunch of aggregating anemones on an exposed rocky shore on the edge of Skookumchuck Narrows, summer 2002.
Giant Pacific Chiton
AKA Gumboot Chiton
Cryptochiton stelleri
Description: A very large chiton growing up to 35cm long with a red-brown sandpaper like girdle that covers the entire dorsal side with no valve showing.
Ecology: Found in low intertidal water to 20m deep throughout coastal BC.
Notes: Apparently this is the largest Chiton in the world, small young ones used to be eaten by some aboriginal peoples. This one was found in the low intertidal zone of a small bay in Skookumchuck Narrows Provincial Park.
Mossy Chiton
Mopalia muscosa
Description: Valves are brown, gray or black, may have white stripes, Girdle is covered with characteristic stiff hairs making it look mossy or fuzzy; grows to 7cm long.
Ecology: Often found on top of rocks in the low to mid intertidal zone and in tidepools.
Notes: Often observed on top of rocks because they do not hide from daylight as most chitons do. This one was found on the side of a rock in a small bay in Skookumchuck Narrows Provincial Park, summer 2002.
Pacific Blue Mussel
Mytilus trossulus
Description: A bluish black mussel with some variants being brown or black. Smooth wedge-shaped shells grow up to 11cm long, but are usually around 4-6cm.
Ecology: Found in more sheltered areas from mid-intertidal to subtidal water 40m deep. Common throughout the Georgia Straight (southern coastal BC) where it is the dominant mussel. Range is from Alaska to Mexico.
Notes: Produces thread like sticky fibers to adhere to substrate, usually rocks, but common on wharf pilings too. Mussels feed on plankton that are filtered out of the seawater pumped through their gills by tiny cilia. Introduced mussels have recently been found to be hybridizing with the Pacific Blue Mussel. This group was found on a log trapped in the intertidal zone of a small bay in Sechelt Inlet, July 2003.
Giant Pacific Octopus
Octopus dofleini
Description: Reddish or brownish in colour, may change colours according to mood and background colour. Arms spread to 3m across, rarely up to 9m across. The largest octopus in the world, the largest measuring nearly 600lbs.
Ecology: Found in tidepools and rocky areas at low intertidal zones to subtitdal waters to 500m deep. Ranges from Alaska to southern California.
Notes: If you find one on a beach or stranded in a tidepool do not pick it up as it can bite. The right photo was taken at Egmont wharf on the Sunshine Coast where a fisherman had caught it while out catching prawns, summer 2005 photo. The photo on the left shows a larger specimen at Vancouver Aquarium, March 2006 photo.
