Algae are an interesting group of organisms. They have typically been classified in the Kingdom Plantae but are now sometimes considered to be in the Kingdom Protista, better known for single-celled microscopic organisms. Algae occur in three general groups named after their colour – green, brown and red.
Shown above is some algae soup, actually a mixture of bull kelp, rockweed and surf-grass. Although it looks like an algae, surf-grass, found on rocky sites, is actually a vascular plant as is its mudflat counterpart, eelgrass.
Some green algae are single-celled and some green algae occur on land; you can see them on the sides of buildings or fences. Most algae are larger though and occur in freshwater and marine environments. Larger algae, especially the brown algae in oceans, are called kelp.
Floating on the surface of the water on either side of the breakwater is bull kelp. The ones on the exposed side of the breakwater are probably still attached to the bottom of the ocean and are part of an underwater forest that is teeming with life. The bull kelp on the harbour side of the breakwater have probably been torn away from their homes and were brought here by waves and currents. Bull kelp have a bulb-like floatation device that helps to keep the photosynthetic blades closer to the water’s surface. Usually the long blades of the kelp that were attached to the bulb have been torn away. The blades look like leaves but every cell is pretty much the same as every other one so the blade looks more like a long sheet of paper. It is attached to a long stalk called a stipe and is anchored to a rocky bottom by a clump of tendrils called a holdfast. The holdfast, stipe and bulb are often seen washed up on the beach.
Here’s a mat of bull-kelp that’s surrounded a diving ball. Ogden Point is a popular diving spot in Victoria.
The brown alga Fucus or rockweed has an antler-like appearance and has air bladders as well. Children sometimes like to stomp on the air bladders and make them pop much like they would with plastic wrapping material that has air pockets.
At the far end of the breakwater around the lighthouse are mats of feather boa kelp. They are also usually anchored to rocks with a holdfast. These algae are true to their name and if you are up for a seaweed wrap experience, you can take one from the water and wrap it around your neck, as Anny is below (taken at Botanical Beach near Port Renfrew).
One of the more stunning algae can be seen about two-thirds the length down the breakwater on the harbour side deep in the water. You might see something that looks like the iridescent flash of the side of a fish with a suggestion of neon. This is actually a type of red algae called iridescent seaweed and it is best seen at low tide on a sunny day. Two other types of red algae that you might see washed up on the beach by the breakwater are branching coralline that is white when bleached in the sun (it looks like little bits of rubbery coral) and laver (also called porphyra) which in Japan is called “nori” – you’ve probably eaten some of it if you like Japanese cuisine.
Green algae algae you mights see on the rocks along the shore at low tide include sea hair (Enteromorpha) and sea lettuce (Ulva). You can identify the sea hair because some of them have been bleached white in the sun.
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