Vancouver Aquarium: storm destination

What to do on a rainy, stormy, soggy Vancouver fall day? Visit the aquarium, of course. We had hoped that it would be deserted. Who would drive through all that rain, all that traffic, on a chilly day when you could stay home, read a book, bake a cake? Well, as it turns out, quite a few people, and almost all of them with teary one year olds. Read 'teary' as 'screaming'.

Fortunately the creatures in the tanks didn't seem to care. And in spite of the rain, there were still people willing to stand in the downpour and photograph the belugas. Like us. And that's when we spotted the American Dipper foraging around the edges of the whale tanks. Birding the easy way.


Dippers are always intriguing to me. The last one we saw was in Manning Park, foraging in the rushing waters of a creek. They always seem oblivious to you, until you try to get close. You can view a map of the distribution of American Dipper in BC on the E-Fauna BC atlas page, as well as a photo gallery for the species. In the atlas page, Jamie Fenneman writes: "It is extremely closely tied to aquatic habitats, especially those that are turbulent, cold, and clear, and virtually never occurs in terrestrial habitats beyond the banks of these watercourses. It feeds primarily on aquatic insects and their larvae (caddisflies, dragonfly nymphs, stoneflies, etc.) but will also consume small fish, fish eggs, and flying insects." I suppose the water gushing into the tanks makes for turbulent, cold and clear. And there must be insects in that water.

Oh, and the stars were out..

And they were active! Every tank had a few sea stars moving around the glass, including the sunflower sea star (Pycnopodia helianthoides) (the one in the above photo with fifteen arms). And this one was really moving fast, for a sea star. He/she literally whipped around the glass. E-Fauna BC has an atlas page for this species that outlines biology and general habitat and distribution, and there is a small photo gallery. Under the Biology section, which presents material from Phil Lambert's book Sea Stars of British Columbia, Southeast Alaska and Puget Sound, Lambert writes: "The diet of Pycnopodia helianthoides varies with geographic location and the availability of prey, such as sea urchins, hermit crabs, sea cucumbers, clams and sand dollars...The Sunflower Star swallows sea urchins whole."

This sea star is quite a predator and seems to be frightening to other sea creatures, eliciting major avoidance behaviour. Lambert writes: "P. helianthoides can outrun most benthic species, travelling up to 160 cm per minute. To defend against this predator, some species have developed specific escape responses. The abalone Haliotis accelerates and simultaneously whips its shell back and forth to break the grasp of the sea star's tube feet. The snails Tegula brunnea and Calliostoma ligatum show typical flight responses as well as shell twisting. The swimming scallops Chlamys spp., the California Sea Cucumber (Parastichopus californicus), the nudibranch Dendronotus iris and the anemone Stomphia didemon swim away when touched by this sea star." Outrun? I have a vision of sea star cartwheels, a flashing image of arms in motion. But I have to say, again, this sea star was moving fast. Maybe it was hungry and actively hunting?

Next time we are back at the aquarium, I will have to see if there are sea urchins in the tanks with the sunflower stars. Every visit is intriguing, always something to check out. Though it would be nice to visit when we are the only ones there...

Corals in British Columbia

Until recently, I wasn't aware that BC had corals. I thought corals belonged in the south seas, such as off the coast of Australia in the Great Barrier Reef. But the E-Fauna BC cold-water coral checklist by Glen Jamieson changed that. Based on his list, we have 46 species of cold-water corals in BC, plus additional genera where the species was not identified. Jamieson also provides an introduction to BC corals and says: "Cold-water corals occur throughout the world’s oceans, from the Antarctic to the Arctic and within the Mediterranean Sea. Typically, these corals are found in relatively shallow continental shelf and slope waters (Roberts et al., 2006), 50-1000 m depth, including shelf-edge canyons, deep channels between fishing banks (MacIsaac et al., 2001) and on fjord walls. However, cold-water corals, mostly gorgonians and hydrocorals, in the eastern North Pacific are most abundant in a much narrower depth zone." So there you have it. Not only does BC have corals, but they are found in such intriguing places as fjord walls. This is really an interesting write up and talks about sea mounts and things under the ocean that most of us don't know about.

So what exactly is a coral? Here is Wikipedia's definition: "Corals are marine organisms from the class Anthozoa and exist as small sea anemone-like polyps, typically in colonies of many identical individuals. The group includes the important reef builders that are found in tropical oceans, which secrete calcium carbonate to form a hard skeleton."

Cold-water corals are not well known, and studies are still underway to discover occurrences of them. They support their own fauna, and, as the BBC reports, these are often species scientists thought were extinct. Not surprising in a group that is mostly 'invisible'.

On a visit to the Vancouver Aquarium, we saw one species of coral--a gorgonium. But corals are another group that we know little about, and need to explore more. We definitely have to go back to the aquarium to see what other species they display, and maybe try for a clear, unblurred, photo.

Pink Candelabrum Gorgonium (Paragorgia pacifica)

Note:

And not only do we have corals, but we also have sponges. The checklist of sponges on E-Fauna even provides links to photos from the Khoyatan Marine Lab website.

Visit lophelia.org for more information on cold-water corals.

Read the World Wildlife Fund brochure on cold-water corals.

Read more about cold-water corals from the BBC.

Visit Wanderin' Weeta, who always has some interesting hidden world to show us. Today it's bryozoans.

Rockfish, Clams and Mussels at Granville Island: a short biology tour

A Granville Island outing is always interesting, from the people to the food. Yesterday we visited the seafood shop ...always a great biological field trip. Here's a sample of what we found:

We found containers full of Manilla clams (Venerupis philippinarum). This species was introduced in BC in the 1930's. They are residents of the intertidal zone.

And there were Rockfish. This one is probably the Red-banded Rockfish (Sebastes babcocki), which is found from California to Alaska. Some of this species have been found to be 106 years old. In BC, they can be mature at 17 inches, so this one is probably a juvenile--it was about a foot long.

And, of course there were salmon, in this case Spring or Chinook Salmon (Onocorhynchus tsawytscha).

And there were containers of honey mussels...I'm not sure what species these actually are, but we are looking into it. They seem to be farmed mussels but of what origin? A note I found on the web says: "The mollusk, which Clark describes as “one part Mediterranean mussel, one part Atlantic mussel and one part Pacific mussel,” is so named because of its brownish shell and sweet taste." A hybrid? An introduced species? More on this later...

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Earthworms: Ancient fauna of BC

Earthworms have become a recent interest for us. We are complete neophytes when it comes to their identification, their biogeography, and basically about anything 'earthworm'. But recently we have been reading about them and have learned some interesting facts. Until the last few weeks, we thought that all earthworms in Canada and BC were introduced from Europe, and that there was no native earthworm fauna. But although this was thought to be true for years, researchers have now shown that, although most earthworm species here are introduced, there are four native species in Canada--all found in BC. These are Arctiostrotus perrieri, Arctiostrotus vancouverensis, Bimastos lawrenceae, and Toutellus oregonensis. None of them have common names, unlike the introduced European species, but they are referred to by the earthworm specialists as 'ancient earthworms'. These four ancient species survived glaciation along the coast of BC (and Washington and Oregeon) in what are called 'glacial refugia'--places where the glaciers didn't go, and they can be found in BC on Vancouver Island and in the Queen Charlotte Islands in BC (one species).

Altogether, there are 24 species of earthworms reported for BC (see the E-Fauna BC checklist), and there are a number of papers on earthworms in BC by three main authors: William Fender, Dorothy McKey-Fender and Valin Marshall. One of these papers has distribution maps showing where earthworm species have been collected in BC. Looking at these, it is easy to see that, aside from the limited distribution of our ancient species, all of our earthworm species are mostly found in the southern half of the province, more or less, which may mean that they are temperature limited.

But aside from learning about the presence of native earthworms in BC, and where they are found, we also learned other things about earthworms: our introduced species come from Europe; some live deep in the soil, some live mostly in the upper part of the soil, close to the surface, some live above ground; some species will drag leaves into their burrows; some have permanent burrows; they produce cocoons, from which juveniles earthworms emerge; identification is based on various anatomical features that include length of adults, diameter of adults, the number of segments, colour, and so on; identification of juveniles is difficult if not impossible; identification of adults is possible, with practice and knowledge about their anatomy. There are other interesting earthworm facts which you can find in the introduction to earthworms or in the Earthworms of BC on E-Fauna BC.

We took a look at the earthworms in our garden this morning, to see what we could see. But we could only find small juveniles (photos below, the head is on the left, tail on the right--oops, that's the other way around, thanks Garden Lily!), which we can't identify. We will have to find some adults to look at-- maybe when this downpour stops. But even then it will take some practice to be able to put names to them.





I have to wonder, given the amount of shipping and traffic from Asia and China, are there no introductions from there? An investigation for another day.

Read about the giant earthworm of Oregon.
View a video of Australia's giant earthworms.
View a drawing of the parts of an earthworm


References:

Marshall, Valin G. and William M. Fender. 1998. Native Earthworms of British Columbia forests. Northwest Science 72. Special Issue 2. Pages 101-102.

Marshall, Valin G. and William M. Fender. 2007. Native and Introduced Earthworms (Oligochaeta) of British Columbia, Canada. Megadrilogica 11 (4): 29-52.

McKey-Fender, Dorothy, William M. Fender and Valin G. Marshall. 1994. North American earthworms native to Vancouver Island and the Olympic Peninsula. Canadian Journal of Zoology 72: 1325-1339.

Reynolds, John Warren and Mark Julian Wetzel. 2008. Terrestrial Oligochaeta (Annelida: Clitellata) in North America, including Mexico, Puerto Rico, Hawaii, and Bermuda. Megadrilogica 12 (12): 157-208.

Sea Otters: A tool using marine mammal

Sea Otters (Enhydra lutris). These are creatures that we don't see very often, just now and then. This photo was taken at the Vancouver Aquarium, but we have seen them in the wild twice now, off the coast of Vancouver Island, floating among the kelp in rocky areas. They feed on a variety of marine invertebrates (including sea urchins, molluscs, sea stars and crustaceans) and sometimes fish. But here is the interesting things about them--they use tools. When I think of tool-using animals, I think of chimpanzees and crows and their relatives. Sea Otters don't come to mind right away. But Sea Otters use rocks to open mollusc shells, often pounding them while floating on their backs. They also sleep while they float on their backs, sometimes 'holding hands' so they don't drift apart. And they feed while floating on their backs. Young Sea Otters will often be seen sleeping on their mother's belly.

The Sea Otter is an endangered species in Canada, and was extirpated from our coastal waters by the early 1900's--a result of overhunting for their fur. Populations we see today are mostly a result of reintroductions of animals from Alaska.

Sea Otters are members of the weasel family (Mustelidae), and inhabit the coastal areas of the north and east Pacific Ocean, including the coast of Japan and the coast of BC. They can be mistaken for River Otters, so check carefully when you think you see one. We have seen River Otters along the ocean shore often, sometime in marinas where they playfully run in and out of moored boats--maybe checking for fish leftovers.


View a photo of sleeping otters holding hands.
View a photo of otters floating among the kelp.

Read more about sea otters in BC.

References:

Biffard, Doug. nd. Sea Otters and the Role of Provincial Protected Areas in Recovery. BC Ministry of Water, Land and Air Protection. Online. Available: http://www.llbc.leg.bc.ca/Public/PubDocs/bcdocs/400484/biffard_edited_final_may_7.pdf

Happy Halloween, a birders perspective

Halloween may be a time of ghosts, and bats, and cats. But for birders, it's still about birds...

Lulu Island: a wild place to be

Lulu Island (a.k.a Richmond, BC), has some flavourable moments, images that stay with you, sights and sounds that speak of more than city life. Lulu Island has a definitely wild flavour. Located at the edge of the ocean, the island is often bathed in fog when the mist rolls in off the sea. The sound of fog horns can be with us for days at a time. Sea planes fly low over our houses as they make a landing on the Fraser River, the buzz of their engines a part of life here.

And the snow geese. Thousands of snow geese makes Lulu Island their winter home, their arrival announced with bubbly shouting that make you think a party is about to start. Walking the west dyke along Sturgeon Banks at this time of year is a tradition for many of us. No matter how many times you have seen snow geese, you still want to watch that spectacle of white wings against dark gray skies. When the geese take off en masse, rising from the cattails and ponds in one large noisy flight, it is totally mesmerizing. Everyone stops to watch.

But there is a little extra flavour out there along the marshlands. Partway along the dyke, the air fills with 'country'. The aroma of cows. In this spot, the snow geese swirl and land and flutter about amongst Harold Steves' herd of Scottish cows--Banded Galloways. The Steves farm is a relict here, 11 acres of farmland surrounded by subdivision, with cows grazing the nearby pasture and open marsh. Cows and a very big bull. It makes a walk along the dyke that much more interesting, that much more flavourable.

Snow geese and cows.

The cows wait patiently to be let out of the pasture and into the barn.

The cows are ignored by the snow geese.

The sleeping bull.

The bull is an awful lot bigger than the cows in the pasture.

Just behind Steves' farm sits the urban landscape of Richmond.