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I have chosen a section of beach just north of Volunteer Park, in Kitsilano, Vancouver.
(49.2720355, -123.1693128)
Observations
General landscape
My first field observation took place on Friday, 12 February, from 12:17 to 13:06. The weather was cold (approx. -2 degrees Celsius) and overcast. According to Fisheries and Oceans Canada (tides.gc.ca), the predicted low tide was at 12:38 and was 3m (relatively high, the next low tide at 23:50 is predicted to be 0.6m).
Figure 1. The beach north of Volunteer Park seen from the edge of the water at low tide, 12 February 2021. A. The entrance to the steps down to the beach. B. Hill slope, with some vegetation (mostly grass and ivy). The slope extends 2-3m, with an elevation drop of 4m. C. Big rocks and logs, extends 2-3m, 1m drop. D. Sandy beach, extends 4m, 1m drop. E. Intertidal zone, 14m to edge of water, less than 1m elevation drop. All measurements are visual estimates.
The selected site (Fig. 1) is the tidal area of the beach found down the steps from Volunteer Park.
Vegetation
On the hill there is trees, some grass, and (especially around the tree, close to the concrete wall to the east) some ivy. I saw minimal land vegetation past the large rocks.
I saw a few different kinds of seaweed, some more clearly different than others (Figure 2). They looked different but I will have to spend more time looking at the seaweed at the beach with an identification guide in order to know. The only seaweed that was further up on the beach was the reddish-brown “finger-leaf” seaweed.
Figure 2. Photographs of seaweed found at the beach site. First to last: “mossy” green seaweed, “kind-of-mossy-but-with-longer-strands” green seaweed, “slimy-sheet” green seaweed, “finger-leaf” greenish-brown red seaweed, “fuzzy” red seaweed, “finger-leaf” reddish-brown seaweed.
Animals
From the big rocks down through to the edge of the water, I found many shells both whole and in fragments. I could identify lots of mussel and oyster shells, and fewer clam shells. (Fig. 3) Living examples of all of those were in the wet intertidal zone. (Fig. 4) Towards the bottom of the sandy beach, very little sand was visible because of the amount of small pieces of shell.
Figure 3. Shells found on the sandy beach. A. Oyster shell. B. Mussel shell. C. Broken clam shell.
Figure 4. Top: Mussel attached to rock. The hairs of the “beard” are visibly connecting the animal to the rock. Bottom: Oyster in a shallow pool, covered in barnacles.
I also spotted evidence of buried animals. I found holes in the mud of varying size (Fig. 5), saw a couple spurts of water (as some clams do), and what looked like the open razor-edges of buried mussels (Fig. 6).
Figure 5. Small holes in the mud in the intertidal zone.
Figure 6. Open shells of bivalves, underwater.
Barnacles were visible on most hard surfaces in the intertidal zone, including rocks and other animals (Fig. 4 bottom). I did not witness any barnacles open to catch food.
The most prevalent birds were crows, with some seagulls mostly flying overhead, and a few Barrow’s goldeneye ducks swimming near the water’s edge. The crows appeared to be digging in the intertidal mud, and varied in group size from individuals to large groups (Fig. 7). They were often quite noisy.
Figure 7. Crows in the intertidal zone.
Surprisingly for me, considering the cold weather, I also saw some small flying insects walking on some of the rocks (Fig. 8). They moved quickly.
Figure 8. Small winged insects, seen moving on rocks in the intertidal zone. Three individuals are circled in red.
I did not see any sea stars, anemones, or jellyfish, all of which I have seen before at low tide on beaches in Vancouver. It is possible this absence is because the low tide at the time was not very low, but also I have not looked closely at this beach before and they may only be present elsewhere.
People
This beach is located in between Kitsilano beach and Jericho beach, and when the water is not too high, it is a popular spot for taking a walk. While I was there, many people walked past. Some people were just out for a walk, but many also had dogs. Most of the dogs were unleashed, and often ran in the intertidal zone. I especially noticed dogs occasionally chasing the crows.
Note about identifications:
Any animals identified above are not listed with the Latin binomial names because I did not consult a guidebook, so the identifications are just from my own previous knowledge, to the best of my ability, and may not be exact or fully accurate. In my next field observations, I hope to be more specific as I narrow the focus of the field study.
Potential Research Questions
- How do the species of animal vary from the upper- to the lower-intertidal zone? Are some species or animal types restricted to one section of the intertidal zone? Is there variation between individuals (eg. size) of a species as they get closer or further from the top of the intertidal zone?
- What are the different species of seaweed present in this area? Do they vary in distribution? Are some seaweed species often close to particular animals?
- What is the effect of people on the activity in the intertidal zone? Does the presence of unleashed dogs reduce the number of birds?
