A mix of intertidal sponges can be found on exposed rocks at low tide.

Around the front of the island a series of large rocks on which multitudes of Purple Stars, Green Surf Anemones, Mussels, Gooseneck Barnacles and much more are easily accessible at low tide. Each rock is surrounded by sand so it is possible to view these fascinating intertidal organisms without harming them or stepping on other creatures.

The last time I visited Schooner Cove I thought I would check out the second island in the cove. Viewed from the south end, it doesn’t look like much but I discovered that the north side of this second island is very interesting. It is carved into a series of surge channels which host walls of intertidal life. At that time, it was already well past low tide and it wasn’t ideal (or very safe) to explore. I made a mental note to return and this past week both tides and days off coincided to allow a second visit. On this visit to Schooner Cove I arrived about 15 minutes before the low and the narrow sandy channels were accessible although some care was required to monitor wave action.

Sea Pork (Aplidium sp.?) and Purple Intertidal Sponge(Haliclona permollis?).

One of the things that was most noticeable was the large patches of sponges that covered the walls of these narrow channels. At least three different species were visible ranging in colour from a rich purple to bright red to green to a slimy gelatinous looking orange/yellow.

I was interested in learning a little more about Pacific Northwest sponges and found some excellent information in Stefani Hewlett Paine’s book Sea life of the Pacific Northwest which has a great section on sponges (as well as the life histories of a variety of other intertidal organisms).

Sponges are very primitive animals that are essentially a collection of unorganized cells – there are no specialized tissues, no organs, no nervous system, no sensory cells, or even a mouth. The structure of a sponge is based on a simple form; a vase-like structure that is attached to something solid at one end and open at the other. Water is drawn into the sponge through very small openings by means of the beating flagella of collar cells which line the interior of the vase. Minute food particles in the water are taken in by individual cells and nutrients are distributed by bodies called amoebocytes. Waste water exits via a larger opening (that often looks like a small volcano) called an osculum.

Yellow-Green Encrusting Sponge (Halichondria panicea) was common at Schooner Cove in Pacific Rim National Park Reserve. Note the volcano-like oscula.

Amoebocytes also play a part in providing the sponge with structure, forming spicules (slivers of glass, calcium or fibre) that keeps the sponge from collapsing and closing off the water canals and cavities. They also play a role in reproduction, producing both eggs and sperm that are released into the water. The timing of the release of gametes is staggered to ensure that cross-fertilization occurs. In addition to reproducing sexually, sponges are also able to reproduce asexually and have a remarkable ability to regenerate. They are able to reform into a complete sponge even if the individual cells of the animal are separated when strained through a fine mesh silk!

Purple Intertidal Sponge (Haliclona sp.) is one of the common intertidal sponges.

Sponges have few predators, probably due to the unappealing texture, the spicules, and the foul smell of some species. However, some nudibranchs do prey on sponges and sea lemons, for example, prefer to eat Haliclona sp.

The slimy texture and orange/yellow colour give Sea Pork (Aplidium sp.) its common name.

Sponges are definitely interesting organisms to look for in the intertidal zone. If you can get past their gross, slimy appearance they really are quite fascinating!

If you’ve enjoyed these close up photographs (and who can’t look at a gooey sponge without wondering if there is anything else worth looking a little closer at) check out Macro Monday for more great images of the small and curious.

Other similar or entirely different spineless organisms can be found at Circus of the Spineless, this month hosted by Hectocotyli.

My destination was the far island on this hike. I usually focus on island that is the first one encountered when entering the bay but on a previous visit I had checked out the second island and thought that it was well worth a closer look. The south side of this island (which is what one sees when entering the cove) is unremarkable. The north side is very interesting. Wave action has carved a series of narrow channels through the rocks making access to walls of marine life very easy. The bonus is that it is possible to explore these channels without stepping on organisms since the bottoms are covered with hard packed sand. One must be extremely cautious of what the tide is doing and the condition of the surf since these surge channels can also concentrate water movement so that waves move quickly up them.

A trio of Monterey Sea Lemons (Doris monteryensis) sit next to their ribbon like egg masses.

Since the low was mediocre and the tide was turning I didn’t have a great deal of time. Among the many different forms of life living in these channels, a pair of Sea Lemons caught my eye. They were stuck tightly on the rock wall next to their ribbon-like egg mass. Sea Lemons do look a little like lemons – they are yellow and have a knobbly texture and are about the size of a large lemon.

I’m not 100% sure on the identity of these Sea Lemons. There are two very similar looking possibilities: Noble Sea Lemon (Peltodoris nobilis – also know as Anisodoris nobilis) and Monterey Sea Lemon (Doris monteryensis – also known as Archidoris monteryensis). According to the Sea Slug forum, the former has a white frill around the edge of the ring of gills at the back of the animals, while the latter’s gill colour matches the colour of the body of the animal. Looking at the picture, I think that the gills are more yellowish than white, suggesting that these are Doris monteryensis.

I didn’t have enough time to examine these beautiful dorids for long. The tide was on its way in and I managed to take only a couple of photographs before I felt it wasn’t safe to continue. In examining the photograph while processing it with Photoshop I realized that there actually appears to be three nudibranchs in the image – can you see all three?

For more photographs of British Columbia nudibranchs check out the Island Nature article “Madrona Point Nudibranchs” by Lisa Graham.

Tangled Bull Kelp (Nereocystis luetkeana)

I found these Bull Kelp stranded on the beach at Florencia Bay in Pacific Rim National Park Reserve. I was fascinated by how intricately these kelps were intertwined, a fine tangled mess.

It appears that anchor that they chose just wasn’t heavy enough. Perhaps there’s a lesson here…

Two participants look at some kelp greenings.

Last week I joined some folks with Raincoast Education Society in Tofino as they conducted a beach seine in the eelgrass beds on the shore right in the middle of town. It was a great opportunity to get re-acquainted with some of the fish that can be found in the extensive eelgrass beds around Tofino and meet some new ones. The beach seine was a joint effort between Raincoast and Parks Canada and staff from both organizations were on hand to help identify fish and make connections between the fish and the eelgrass ecosystem.

Tube-Snouts

It was pretty challenging to take photographs of the fish but I did manage to get some images of Shiner Perch and Tube-Snouts. In addition to these fish we also caught Penpoint Gunnels, Crescent Gunnels,  a large Whitespotted Greenling, a Rosylip Sculpin, Pacific Staghorn Sculpin, an English Sole, Threespine Stickleback and many more. I was amazed at the diversity of fish and crabs that we caught not more than 3 metres from the shore.

Shiner Perch

The Raincoast Education Society has another beach seine scheduled on Thursday, August 26 between 9:00 am to 10:30 am at Tofino Sea Kayaking  (320 Main Street) in Tofino, British Columbia. If you’re in town make sure to drop in and check out the seine – it’s “in-seine” fun and educational to boot!

Josie from Raincoast Education Society eyes a Penpoint Gunnel

Raincoast Education Society offers a range of public walks in the forests, beaches, intertidal zones and mudflats around Tofino and Ucluelet on the west coast of Vancouver Island.  FMI contact Raincoast at 250-725-2560. More about this seine can be read in the article The Unseen Between the Seine on the Westerly News web site.

Moon Jellies often wash up on sandy beaches on the West Coast of Vancouver Island.

Often when jellyfish are washed up on the shore at Long Beach they don’t last long. At first glance this stranded Moon Jelly (Aurelia labiata) appears to be forgotten.

Water-line Isopods (Cirolana kincaidi) are active scavengers along the surf-line.

A closer look reveals that some of the beach’s most aggressive scavengers are hard at work dealing with the jelly’s remains. Water-line Isopods (Cirolana kincaidi) commonly follow the line of the tide as it moves up and down the beach, covering anything that is dead and devouring it very efficiently. In fact they are so aggressive that if you stand motionless as the water washes over your feet you may soon be covered with nasty red bites!

Water-line Isopods (Cirolana kincaidi) quickly devour anything dead that has washed up on the beach.

Keep an eye out for these superb scavengers the next time you’re visiting the surf pounded sandy beaches of Pacific Rim National Park Reserve. They’re fascinating to watch, at least if you’re safely wearing rubber boots!