Anemones in Nanaimo
On April 29 we had a very calm ocean and a low tide as well. We encountered many sea stars (mainly Ochre and Leather Stars) but also the Giant Plumose Anemone (Metridium farcimen). It is really weird to see them above the waterline; they appear to be hanging balloons full of water. Under the water they form a nice umbrella with many tentacles. Did you know they only have one digestive system; the mouth is also the anus! The tentacles are festooned with millions of cells called cnidocytes, each of which has a tiny, harpoon-like mechanism. Prey capture is a common function of these specialized cells, many of which contain an associated toxin.
The body type of the anemone is called the polyp where there is a ring of tentacles and mouth/anus configuration atop of a columnar body. Cnidarians can also have the medusa type, where the layout is hanging down and free-floating, a jelly is a great example of this.
If you do not have a kayak and you would like to see them up close: check the underside of the docks in the Nanaimo marina's. I bet you will spot them there as well!!
Sea Stars in Nanaimo
We are getting closer to the solstice and the tidal differences are getting bigger. Our kayak tours are sometimes at a low tide and then we see a lot of sea stars (or starfish but biologists like to call them sea stars ;-) ). The most common sea stars in the Nanaimo area are the Ochre Sea Star (Pisaster ochraceus) and the Leather Star (Dermasterias imbricata). The Ochre Sea Star is purple or orange and feels very tough, almost like a rock. The Leather Star is orange and feels like soft leather.
Both species almost disappeared in 2013 due to the Sea Star Wasting Syndrome and is possibly caused by a single-stranded DNA-virus and/or environmental changes like the warming of the ocean, i.e., still not fully understood. Luckily the Ochre Sea Star and the Leather Star bounced back relatively quickly but some sea stars like the Sunflower Sea Star (Pycnopodia helianthoides, with 16 to 24 limbs!) which eat the Ochre Sea Star is still not seen in the Nanaimo waters.
During our tours we explain how the sea stars live, move and eat. It is always great to see them sometimes in big clusters hanging from the rock walls.
Richard Römer likes to roam around on Vancouver Island and creates exceptional adventures on Vancouver Island, the Sunshine Coast, Discovery Islands in British Columbia, Canada