Dave Ingram's Natural History Blog

I’m happy to say that the rather ubiquitous Glaucous-winged Gull is a species that I’m at least able to identify in both breeding and non-breeding plumage. After reading Hugh’s post about Spring Gulls coming into breeding plumage I thought that I would keep an eye out for them in the Comox Valley. There is a large breeding colony nearby on Mittlenach Island and Glaucous-winged Gulls are common in the winter here on the coast. Sure enough, a little searching this week quickly turned up a Glaucous-winged in its breeding finery. Note the white head, fairly heavy bill, dark eye, and grey mantle (back) and wingtips. Compare the photograph below with a Western Gull I found at Parksville Bay.

Glaucous-winged Gull (Larus glaucescens) in breeding plumage - note the non-breeding plumage bird in the background.

The fact that some of the large gulls take up to four years to mature means keeping track of up to eight different plumage stages. Then throw in some hybrids just to keep you off balance. Some gulls in winter plumage are fairly distinctive but for the most part, I’m happy to wait until gulls are in breeding plumage before identifying a gull conclusively. I’ll admit that I’m no gull expert and lack what Sibley describes as the “patient and methodical” approach needed to become better. Maybe having a two and a half year old and an eight month old has something to do with that.

Non-breeding winter plumaged Glaucous-winged Gull (Larus glaucescens) in flight.

I’m always on the lookout for shells of all sorts when I’m out walking the beach. I don’t collect them but simply enjoy picking them up, taking a closer look at them and then returning them to the beach for someone else to find. After all, shells that are taken home usually end up in shoe boxes tucked onto the top shelf of a closet somewhere. Or if they’re on display they always need dusting. Better to leave them on the beach.

The beach at Point Holmes, Comox, BC.

Point Holmes in Comox, BC is an excellent place for beach exploration. At low tide there is a perfect mix of both cobblestone habitat and sandy beach habitat which results in a wide variety of marine life. Throw in a few large boulders and you’ve got the potential to find Purple Seastars (Pisaster ochraceus) on a good low tide. At other times of the year I’ve found over a dozen Monterey Sea Lemons (Doris monteryensis) in the tide pools at Point Holmes.

In addition to the Wrinkled Dogwhelks, Pink-tipped Anemones, and Red Rock Crabs that I found at Point Holmes on my last afternoon on the beach I also found the shell of a native Pacific Littleneck (Protothaca staminea). Since finding and photographing the non-native Japanese Littleneck (Venerupis philippinarum) on the mudflats of Comox Bay I’ve been searching for the somewhat similar looking Pacific Littleneck in order to compare the two.

The outer surface of the shells of the Pacific Littleneck (Protothaca staminea) showing the round shape of the valves and the latticed surface.

A quick look at the upper surface of both of these Littleneck clams is sometimes enough to identify them correctly. The Pacific Littleneck is rounder in shape than the Japanese Littleneck and mature specimens lack the patterning that is characteristic of the Japanese Littleneck. Keep in mind that immature Pacific Littlenecks often have patterned shells so assuming that a patterned shell is a Japanese Littleneck can be a mistake. Mature Pacific Littlenecks have an outer shell surface that is typically white to brown in colour with a lattice like structure (radial lines crossing the comarginal growth lines form a grid). Both of these species grow to around 7.5 cm in length.

Read more about the Pacific Littleneck Clam

This weekend I spent some delightful time poking around in tide pools at Point Holmes near Comox, BC. With the fantastic weather of the last couple of days and the low afternoon tides it is an excellent time to be exploring the sea shore. Point Holmes is always productive since it is a mix of sand and cobblestone with a few big boulders thrown in to make things interesting.

I made my way out onto a large cobblestone bar following the dropping tide. After discovering a small cast of Red Rock Crabs I ventured out toward the far edge of water. One of the rules of beach exploration is to move slowly. Walking carefully lessens your impact and you’re more likely to see some of the small things that are often missed.

Here’s just a few of the things that I saw on the beach this weekend:

Purple Encrusting Sponge (Haliclona sp.) plus some bryozoans, a few small snails and a limpet!

This Purple Encrusting Sponge (Haliclona sp.) is fairly easy to identify due to its distinctive colour and prominent oscula (excurrent pores). The sponge is soft and velvety to the touch. Note the other organisms on this rock – what appear to be some bryozoans (the mesh like pattern) and some small snails.

Sea Oats - the distinctive egg mass of a Wrinkled Dogwelk (Nucella lamellosa).

I knew that these were eggs but was unsure of what type of snail laid them until I found more of them and a rout of Wrinkled Dogwelks (Nucella lamellosa) at the base of a very large boulder in the middle of the cobblestone beach. The egg masses are commonly called sea oats because of their distinctive appearance.

Read more about Point Holmes

Looking across a shallow tidepool to a cobblestone bar at Point Holmes.

I headed out to Point Holmes this afternoon to look for and photograph a selection of beach rocks for an upcoming column that Jocie is writing. As with all trips to the shore of the sea it is very easy for a naturalist to get pleasantly off track. I was a little overwhelmed looking for something a little different from the ubiquitous granites and basalts that make up the pebbles on this part of Vancouver Island when I noticed that the tide was still going out and a cobblestone bar was now accessible. Having learned my lesson at the Filberg mudflats I was appropriately prepared to do some tide-pool exploring and waded through the shallow water in my rubber boots.

Close-up of a Red Rock Crab (Cancer productus).

It was then that I noticed the Red Rock Crabs (Cancer productus). Some were digging into the sand and underneath rocks as the water level dropped while others were making their way to deeper water on either side of the narrow bar that was emerging. It was a perfect opportunity to photograph these crabs since they hadn’t quite settled into their hiding places to wait out the low tide. It was interesting to see so many (at least a half dozen) at this time of day since they are generally more active at night.

Pincer of the Red Rock Crab (Cancer productus) - note the black tips.

Red Rock Crabs are a distinctive crab and easy to identify. Like the name suggests, this crab is a brick red in colour. The tips of the pincers are black and the “teeth” bordering the edge of its carapace are rounded. These differences serve to separate the Red Rock Crab from the Dungeness Crab (Cancer magister). The latter is generally a sandy gray/brown and lacks the black tipped pincers. The “teeth” bordering the edge of the Dungeness’ shell are sharp – I remember this feature by reminding myself that sharp items are likely to be found in a “dungeon.” Dungeness Crabs tend to grow to a larger size, up to 28 cm across the carapace compared to up to 20 cm across for the Red Rock Crab.

Don’t get crabby, there’s more to see and read

Yesterday I was in charge of the kids for a couple of hours so I decided that a trip up to Campbell River was in order. I figured that after about 3o minutes of driving they would both be asleep and I could do some roadside birding along the shoreline. In particular, I was hoping to find some Brandt’s Cormorants since that is a species I need to add to my 2010 Year List. Campbell River has produced Brandt’s in the past and I had my fingers crossed for a repeat.

Double-crested Cormorants on a float. Apologies for the grainy image - have I mentioned recently that I'm still looking for a good telephoto lens?

Unfortunately, I was only able to locate some Double-crested Cormorants near the coal loading terminal. I was limited to locations where I could park my car and get out and bird – walking wasn’t an option unless I wanted to wake up my charges. As they say, “Let sleeping babies lie and enjoy the quiet.” The Double-crested Cormorants were still pretty neat to see though – I never get tired of watching them spreading their wings out to dry.

Back in 2004 during the Deep Bay Christmas Bird Count I had a little more success and actually saw all three cormorant species in one place. Here’s the post that I wrote back in December 2004:

Flashback to Deep Bay CBC, 2004

By far the highlight of the count was a “lesson” in cormorant identification. At the south end of our area we returned again to the water and were lucky to view all three possible cormorants resting on one raft near the shore.

All three cormorants - Double-crested, Pelagic, and Brandt's.

In the photograph above the double-crested cormorant is identified by both its size and the orange colour of its bill. On the right side of the photograph is a single pelagic cormorant, the bird that is noticeably smaller than the double-crested cormorant behind it. Note also the smaller head and thinner bill and neck of this bird. Finally, a pair of Brandt’s cormorant complete the image. These cormorants are on the edge of the raft closest to the viewer and are facing each other. They are somewhat similar in size when compared to the double-crested cormorants behind them but their bills are dark in colour and their feathers are more “greenish black.” This group of cormorants provided an excellent opportunity to observe all three species and pick out diagnostic identification features.

Fast forward to 2010 – I’ll have to keep looking for the Brandt’s Cormorant. It’s all part of the fun of keeping a year list!