January 8, 2019 – Glen Dennison, “The Fauna of Howe Sound”

Glen Dennison is a citizen scientist and marine life activist with a special interest in technology and electrical engineering. His skills, passions and interests have helped forge a passionate campaign to preserve and study the nine glass sponge reefs that populate Howe Sound and some of the Georgia Straight.

For many years, Dennison has been involved with the Marine Life Sanctuaries Society and the Underwater Council of British Columbia, organizations dedicated to protect marine life and promote safe diving.

In 2017 Dennison was honoured by the Coastal Ocean Awards for his study of Howe Sound’s glass sponge reefs. At the 22nd annual awards, which celebrated B.C.’s ocean leaders at an event at the Vancouver Aquarium Marine Science Centre, he was specifically honoured for his inventive design and application of several technologies to examine the prehistoric glass sponges.


Q&A Transcription

Question: How do you track the silica content in the various inlets along the coast to see what impact that may have on the location of these reefs?

Answer: That’s a good question, the only way we can do that is to take water samples and then have those water samples analyzed. It’s very expensive, so because of the cost, we have not done that yet. But we submitted that idea to the DFO to pay the cost of it and we’ve had some of the researchers and scientists up at SFU offer us the use of their labs to do that work and it’s a good question, and it’s something that is right up at the top of the “to do” list.

Question: Would those sharks attack a human?

Answer: Typically, no. Our divers actually have bumped into them and have pushed them away in the past. They tend to be very docile, the Sixgill sharks. Now having said that, they’re still a shark; I wouldn’t trust it.

Question: Could you tell us a bit about the pollution from the pulp mills in Howe Sound please?

Answer: We’ve seen some changes after Wood Fibre shut down, some increase in life. Other than that, I’ve done no studies on the pulp mills and the dioxin levels in the water, but there definitely was a change. And there also was a change around Britannia, when they shut down the mine effluent, when they stopped that from happening. So, I don’t really have a good answer as to what is going on there with the effects on the life. All I know is that I’ve been diving since 1972 in Howe Sound and I have seen changes there, but I have not documented them to any great degree. But, you can be sure that it has got better.

Question: Could you comment on how the air supply works within the submarine? Ten hours seems like a long time.

Answer: What they do is that they actually have oxygen bottles on there and CO2scrubbers.  So, 10 hours by the way is the time that we had the hatch-closed to hatch-open, but it actually has a duration of about four days I think on it, it’s quite long. So, I think they have lithium scrubbers that they’re using to take the CO2out, and we have an air conditioning unit that’s dropping the water vapour out or the inside of that sub would be completed frosted over on the inside. And what we had happen is the reverse. Because we had cold soaked for so long down at about roughly 40C under water, when we came back up to the surface in September, we frosted the outside of it. Because it took a long time, the acrylic is about two inches thick on that submarine, then while it was warming up we actually had to open the hatch up, and I was using my phone’s GPS to navigate our way back to the Thunderbird Marina at night because the pilot couldn’t see a darn thing under there.

Question: When the reefs are being closed, is that just closed to fishing or is that going to be closed to recreational diving as well?

Answer: That’s actually a really good question and something that we have looked at carefully. It’s just for fishing is what we are working on. Because I’m the director of the Underwater Council, we don’t want to close anything to diving because diving are the human eyes and ears under water. It’s the presence of humans down there that is actually driving the need for protection there so, we are trying to be careful not to close it. But, on the sponge reefs, this is a different question, because the sponge reefs are so rare, the DFO already identified diving as a potential area for damage and they’ve been talking about closing it for diving. So, what we did very early in the game, I had a PADI master diver, he’s a course instructor, design a sponge diving course. And we are asking all of the charters and all of the divers that dive on these sites to take the course, very similar to before you dive on coral in tropical areas, they quite often take you out for a little one-hour training dive off the shore so that you don’t touch the coral, which damages it. We’re doing something similar with the sponge reef just to prevent the DFO from saying ‘complete closures’ or only closures for scientific studies. That’s a very good question.

Question: Who built the submarine?

Answer: The submarine was built by Aquatica Submarines out of West Vancouver. Harvey Flemming is the CEO of the company.


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