That time I rode in a submarine – Sea of Glass Pt 3

By Danielle Ludeman
Reblogged from CPAWS-BC

As we disappeared into the depths of Howe Sound, I peered through the three-inch dome in front of me trying to catch the first glimpse of the sponge reefs below, and my excitement started to grow.  But my excitement was not just about getting to see the sponges up close, or about being deeper in the ocean than I have ever been before – although these were both pretty exciting. As we descended into the depths, I realized the opportunity the submarine dive provided to highlight the need to protect the sponge reefs.

When I was first invited to be a passenger in the submarine I was so excited– I was going to be face-to-face with the beautiful glass sponges! (Anyone who knows me will be able to tell you how much I love sponges). And then of course came slight fear – I was going to be face-to-face with the beautiful glass sponges 250 feet (76.2 m) below the surface of the ocean in a submarine! Almost twice the maximum depth for certified, recreational divers.

As we continued our descent down into Howe Sound, I began to make out creamy, white shapes in the water below. I turned to the Hon. Andrew Wilkinson, a Minister in the provincial government, and Jeff Heaton, the pilot of Aquarius, to tell them excitably that there were sponges below! We had descended right down to the sponge reef, and there were the beautiful glass sponges only a few feet from me.

As a graduate student studying sponges I have been involved in research cruises to study the glass sponge reefs. Because the sponge reefs are found so deep in the Strait of Georgia, conventional sampling methods cannot be used.  Instead, we use a remotely operated vehicle called ROPOS (picture a very large, square, yellow robot) to sample and survey the reefs, sending live video footage of the reefs up to the research vessel on the surface. I watched this live footage of the glass sponge reefs for hours on a tv screen.  Now, I have had the amazing opportunity to experience the sponge reefs with my own eyes.

The glass sponge reefs have given me a sense of awe and wonder ever since I first began my undergraduate studies in Dr. Sally Leys’ lab at the University of Alberta.  These glass sponges form massive reefs that serve as crucial habitat for fish, crabs, shrimp and many other critters.  The sponges also filter massive amounts of water, removing bacteria and excreting ammonium, a source of nitrogen that can then be used by other animals around the reef.

But sponges are not like any other animal. A sponge is an animal without a digestive system or a nervous system, yet it will respond quickly to something in the water such as sediment, causing it to stop filtering. You wouldn’t know it from looking at the sponge reefs, but sponges are almost constantly pumping water through their bodies.  One of the sponge reefs has been estimated to filter over 80,000 L of water every second! And here we have these massive reefs formed from this weird and amazing animal, right on Vancouver’s doorstep.

How have these reefs covered hundreds of square kilometers off the coast of British Columbia and we only just discovered them 25 years ago? How do so few people in Vancouver, in Canada, know that these reefs exist? And how have we, as Canadians, not protected such a beautiful and important habitat?

Protecting the sponge reefs requires public awareness, which is where the submarine dives come in. Until now, most people in Vancouver had never even heard of the sponge reefs.  I am very hopeful that the submarine dives will create the public demand for their protection.

Shortly after the submarine dive event I headed down to Fremantle, Australia to attend the World Sponge Conference (yes it exists).  While I was there I was talking to an old friend about my research. Their response was “Oh! I heard about sponges recently.  It was about some sponge reefs that are only found in Canada.  Is that what you study?” And so the ripples spread.

New article about glass sponge reefs

By Amanda Kahn

Glass sponges are in the news!  A lot lately…  This is fine by me–the more we all know about these amazing deepwater animals, the better.  Maybe one day I’ll have a conversation with a stranger that doesn’t involve me explaining that glass sponges are not the same as “sponges used for scrubbing wine glasses” (though there is such a thing).

Glass Castles in the Sea
Reef-building sponges are giving up their long-held secrets.

by Cheryl Lyn Dybas
Published in Natural History magazine

Anyway, check out the article, which features a lot of the research done by the Leys Lab at the University of Alberta (with some of the work done at BMSC), including how they feed, what they eat, how and where reefs form, how humans may impact them, and why CPAWS-BC is pushing to have them considered for protection.

Studying the globally unique glass sponge reefs

By Amanda Kahn

[Cross-posted on the Students Ensuring our Oceans’ Future blog.]

One month ago, we were busy in the lab at the University of Alberta preparing and calibrating instruments, gathering GPS waypoints, and preparing dive plans. Three weeks ago, we drove and flew to Vancouver Island with our equipment and plans. Two weeks ago, we boarded a ship to study the glass sponge reefs in the Strait of Georgia in B.C.

CCGS Vector

Heading out on CCGS Vector, our home away from home. Credit: A Kahn 2013

The main reef we were studying on this trip was on Fraser Ridge. If you drained the water from the SoG, you’d be able to see the ridge and the reef about 14 km away from Vancouver. Fraser Ridge reef is too deep for us to study directly by scuba (150 to 180 meters deep), so instead we study it with the help of the remotely operated vehicle (ROV) ROPOS. ROPOS is piloted and run by the Canadian Scientific Submersible Facility (CSSF) and functions as our eyes and hands underwater.


ROPOS, our eyes and hands underwater. Credit: A Kahn 2013

With those eyes and hands, we studied the energy use and water pumping capacity of the glass sponges that build the reef. Glass sponges are really amazing animals—they can move huge amounts of water through their bodies, which are basically modified to be amazing filters. 9,000 liters of water can pass through a single sponge osculum (the “chimney” that water is released from by the sponge) each day! And from that, the glass sponges can feed on tiny particles, especially bacteria. This is pretty unique among animals—most other animals that feed on particles suspended in the water (called “suspension feeders”) can only capture particles that are larger by 10 times or more.  We did a lot of great science while on board the ship, and I’m now at the field station in Bamfield, British Columbia, to work with other sponges.  We will all spend the winter back in Edmonton working up the samples and data collected from this trip.

Glass sponge reef

Glass sponges in a reef–check out all of those oscula! Credit: CSSF 2011

I’m happy to be a part of SEOF because I can feel connected to other folks who are near the ocean full-time, can ask questions about logistics before I arrive, etc.  I’m the regional representative for Alberta and in this post wanted to show that being far from the ocean does not mean that we cannot have access to marine animals or study ocean-related issues.  Logistics may be more tricky than driving down to beach for the weekend to do some intertidal sampling, but it’s definitely doable and totally worthwhile.  Contact me if you have questions about the reefs or if you’re in Alberta and have questions about how you can get involved in the marine science community across Canada.

To learn more about the reefs, check out these videos, compiled by Sameena Sherman, a student from our lab:

Glass sponge videos: Animals of the reefs

by Amanda Kahn

Did you know that glass sponges form reefs the size of cities here in BC?  If we were to drain the water from the Strait of Georgia (between the mainland and Vancouver Island, where Bamfield sits), you’d be able to see huge structures built by generations of glass sponges as they grew higher and higher to get into strong water flow.  Among other things, the Leys lab–headed by Dr. Sally Leys at the University of Alberta–studies the glass sponge reefs.  Student Sameena Sherman put together two videos to introduce the reefs and the animals that live in them.  If you haven’t seen the first video, you can find it here.  Check out the latest video, Animals of the Reefs, below!

Land-locked scientists, getting their gills wet…for science!

by Amanda Kahn

As discussed in the previous post, my labmate Rachel and I traveled to the coast to collect more samples for our research on the reef-forming glass sponge, Aphrocallistes vastus.  We drove to Brentwood Bay the morning of our collection dive and went out to our dive site with the help of Pinnacle Scuba Adventures.  Everyone was in good spirits–it wasn’t raining yet, the water was calm, and we were going diving!  While I started talking about our most recent adventure (a.k.a. field collecting trip) in yesterday’s post on the blog, I have now continued the updates on the Leys Lab website.  Check it out to see how we fared during the dive and to learn more about why Rachel and I are studying the glass sponges, and what we’re hoping to learn about them.

Dive site

At our dive site. Credit: R Brown 2013

An introduction to glass sponge reefs

by Amanda Kahn

Okay, as far as we know, glass sponges do not form reefs offshore of Barkley Sound, but the same species that form the reefs in these videos do appear as solitary individuals near Bamfield, and in any case, the idea that sponges form reefs is so awesome that this video should be posted here anyway.  Check out the first installment of a series of short videos about glass sponge reefs, put together by Sameena Sherman from the Leys lab at the University of Alberta.  A transcript of the video can be found below.

Transcript of the video:

Fossils suggest that glass sponges were established by the Late Proterozoic era. In the Jurassic, there were large reefs formed of glass sponges that covered the Northern shore of the Tethys Sea, which is now the area representing Europe and Eastern Canada. Sponge reefs, as a biogenic structure, were initially thought to be extinct until the discovery of the reefs in the Pacific Northwest.

Most glass sponges live in depths greater than 500 metres. Off the coast of British Columbia in the North Pacific, vast reefs spanning hundreds of square kilometres live in shallower depths of approximately 200 metres. This depth is speculated to be favourable for sponge reefs because of high silica content, high food content, high water flow, and cold temperatures reminiscent of the deep sea.

Glass sponges possess a unique silicon dioxide skeleton and syncytial tissue formed by fused embryonic cells. They are typically vase, plate, or tube-shaped.

There are two structural types of glass sponges. Lyssacine sponges have a loose spicule skeleton and are non-reef-forming. Dictyonine, on the other hand, can form reefs due to a fused spicule skeleton. Only 3 species make up reefs; they are Aphrocallistes vastus, Heterochone calyx, and Farrea occa. These species are found throughout the Pacific as individuals; it is only in the northeast Pacific that they form reefs.

You can learn more about glass sponges and see more videos at our website:

The hunt for glass sponge larvae

Amanda loves tide poolsby Amanda Kahn

This past week, I left frozen Edmonton, Alberta for some field work on the coast.  My supervisor (Sally Leys) and I went on the hunt for larvae of glass sponges.  Several years ago, a single larva was spotted in a sponge collected in November or December.  We then found sperm and eggs in sponges this past year, so we decided to go investigate.  This is important because this species of glass sponges forms the foundation of the sponge reefs that populate the straits of western Canada (and so far, form reefs nowhere else in the world), so learning about how and when they reproduce will help us determine what factors might positively or negatively affect their breeding success, and therefore the successful growth of the reefs.

Check out the post documenting our trip at the Leys lab website.

Credit: A Kahn 2012

Also, to see what the reefs look like that these sponges form,  check out the video at this link, compiled by Sameena Sherman of the Leys lab, showing reefs in Hecate Strait.