Sunday, 8 October 2017

The Underwater World

As a solo sailor, Larry took a scuba course thinking it would be a handy way to solve some underwater hull problems on Traversay II. I came along as a dive (and life) buddy, and when the time came to build Traversay III we knew we wanted to be able to dive almost anywhere we could anchor safely. We had a list of necessities which were communicated to and understood by Waterline Yachts in Sidney British Columbia. They constructed not only a marvellous dive boat, but a wonderful all-round steel vessel. So far, we've dived together around 500 times - mostly in cold water.
sea star: henricia studeri

Practically from the start of our diving life 26 years ago we attended marine identification courses. I ended up as a docent at the Vancouver Aquarium shepherding young children through sleepovers with whales as well as helping Grade 11 students learn about the animals in the Wet Lab.

Somewhere along the way we borrowed the graded Linnaeus-based Species List used by our two marine I.D. teachers. When we w
ere in Patagonia 10 years ago, we put together a systematic list under the heading of '14 Dives'. Now we're trying to re-visit those divesites with the same list and methods. Larry takes somewhere between 49 and 73 pictures on each dive - afterwards, I edit the photos, identify the animals and we publish a photo-log of each dive. We're trying to work out whether the animal life here has changed. However, this can only be a rough measure. We've found that even diving the same site at night or returning the next day to the same site, there can be enormous variety.

When I first started diving, I couldn't believe that 90% of what we saw were not flora but fauna - animals. You too might find this hard to believe. A notable and welcome exception to this is the bright pink-coloured algae which greets you every time you leave the surface of the (usually cold, rainy and dismal) places - like Norway, Patagonia, BC, Alaska or New Zealand. You can see it in this spectacular photo of a sea star. The green colour is certainly supplied by a green algae. However, the vivid pink colour on the wall behind it is an algae called 'styletheca'. It takes various forms including little tree-like variations. All told, when you enter the water from a cold and rainy landscape in BC, Washington, Greenland, Alaska or Patagonia and discover the fabulous underwater colours, you instantly see this bright pink colour and can forget the cold and isolation. And although the cold-water places mentioned have their own endemic species, this pink coralline algae is common to all.
anemones: metridium senile

It's a new world when you start 'getting wet' in scuba gear. There's an added boost to that 'New World' feeling. It's the sensation of being able to move in novel ways. Ways you've never experienced aboveground. You can go around, over and under things as if you're in a self-contained little airplane.

We've found that the colours underwater in cold-water venues are among the most varied and spectacular in the whole world. We've also found animals that fit into most of the species we first learned to I.D. in BC. Like this star - 'henricia studeri' here and 'henricia leviuscula' at home. But I admit we can't even make a secure identification with sea stars!

That's because we are only amateurs. To completely define certain species, you need to be able to preserve and dissect them or even have a handy electron microscope handy to differentiate between them!

At 2017-10-08 12:16 (utc) our position was 46°36.78'S 075°27.68'W


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