This majestic system of fjords is home to diverse ecosystems. It’s dotted with forested islands and snow-capped mountains reaching skyward, all carved out in the last ice age. Incredibly, it is also only a short trip from downtown Vancouver. The history Howe Sound (Atl’ka7tsem) beings thousands of years ago with the Squamish people and other Coast and Interior Salish people. Heavily impacted by industrialisation throughout the 20^th century, the area has undergone a dramatic ecological turnaround in recent years. However, the pressure of climate change and an increase in human activity continues to build, which has prompted efforts to designate it a UNESCO biosphere reserve. There are more than 700 biospheres worldwide, 18 of which are in Canada. 

My personal discovery of glass sponge reefs happened in 2019 when I learned about the Glass Sponge Research Team, and I was captivated by the incredible photos they had shot of these prehistoric sites. It was initially believed that glass sponge reefs had gone extinct during the Jurassic period. However, in 1987, they were discovered living in very deep waters in the Hecate Strait in northern British Columbia. Very little is known about these primitive lifeforms except their outstanding capability to filter massive amounts of water and sequester ‘blue carbon’. There are eight sites in Howe Sound that are closed to commercial, recreational and bottom-contact fishing activities, but a further 17 have been discovered (at the time of writing). I clearly remember the first phone call with Hamish Tweed, who leads the Deep Glass Sponge Research Team, because of how passionate he was – not only about the deep-water technical diving, but also the conservation and protection of these sites. From talking to him I knew there was a bigger story to share, and that I wanted to tell it.

While the dive team has been exploring and documenting these animals since 2013 in collaboration with the Underwater Council of British Columbia, a much larger group of citizen scientists have been working on glass sponge reef protection for decades. Glen Dennison of the Marine Life Sanctuaries Society came across his first reef using a homemade drop camera (a combination of PVC pipe, electronics, and ingenuity), while trying to map dive sites for a book on diving in Howe Sound. Seeing a glass sponge is not unique in itself, but what makes these sponges unique is their formation into bioherms, or reefs, which have not been seen in the last 40 million years other than in fossilised remains throughout the world. These reefs are structures of living sponges built on top of dead sponge and rise above the seafloor, offering sanctuary to all kinds of marine life. Reef-forming glass sponge are known to occur only in British Columbia, and Howe Sound is exceptionally special in having the only known reef-forming sponges in water shallower than 40m. Marine biologists at Ocean Wise are continuing with their attempts to grow and study sponge in lab conditions for the first time – to better protect these creatures, we need to learn as much about them as possible.

Glen is the resident expert in diving these sites, having spent years zigzagging across the choppy waters recording the valuable GPS coordinates on his laptop. With his drop camera footage and coordinates coupled with the dive team’s footage, the Marine Life Sanctuaries Society compiled all the necessary data and created a report to hand over to the Canadian government’s Department of Fisheries and Oceans. This report marked the reef locations with an ‘X’, so the government could not ignore them. The threat of damage from human activity is great in Howe Sound due to its proximity to Vancouver, bottom contact fishing, anchoring and a general lack of awareness. Without this group of citizen scientists, it is unlikely these sites would have been protected. Ultimately, the story we set out to tell is how regular people are able to help the environment through perseverance and dedication, even though they receive little recognition and no government funding.

My knowledge of underwater filmmaking extends only to the first three metres of the ocean. The technical divers of the Glass Sponge Research Team use mixed gas breathing systems to access the reefs, some deeper than 60m. Cinematographer Bryce Zimmerman and I relied heavily on Hamish’s experience with underwater filming with his GoPro and the lighting techniques he has developed for these dark waters.

“As you can imagine there is a long list of things that can go wrong working and filming underwater,” Hamish explained. “Unlike a normal on land shoot where you have a team of people that can manipulate the environment, we can’t control our surroundings as we are operating in an alien world. Just to be there for that length of time each of our dive crew are on three separate life support equipment systems. You really have to trust the people you’re with in that environment. There is no verbal communication between the divers, there is also no daylight, so we have to rely on a number of signals using our dive lights to give direction and manage everyone’s safety. This takes years of practice to get a crew functioning like this and I feel very lucky to be working them.”

The first day of filming after COVID-19 regulations were relaxed in British Columbia was a leap of faith. Up to this point in production, our film had no usable underwater footage and almost everything that could go wrong had gone wrong. Even when human and equipment errors were avoided, the fickle winter weather of Howe Sound would scuttle the dive and we’d boat back to Horseshoe Bay without a single frame. But we hoped this day would be different. Bryce and I handed off the deep-water camera housing to Hamish and crossed our fingers – a ritual at this point. The divers were descending to depths of 35m, resulting in approximately 40 minutes to film the reef and accruing 45 minutes of decompression before they could surface. During the dive, we would try to distract ourselves from worry as the fate of our project was out of our hands.

“Our biggest challenge to date is lighting,” said Hamish. “Depending on the shot we are trying to get, we will have two or three divers using huge video lights to bring some daylight to a world that lives in darkness. What really hits me is the sheer size of these reefs. I wanted to try and accurately highlight that in our footage, so we spread the divers out and put our main lighting 6m above to get that wider shot.”

After a tense hour and a half, the divers re-emerged with faces red from the cold Canadian water and to our surprise and joy, the camera equipment functioned correctly! Hamish excitedly told us about the visibility around the glass sponge reef. It wasn’t until hours later when we were able to review the footage that we knew we had something special. This was some of the only footage of this glass sponge reef, which has only been dived by maybe 10 people. We had finally been able to do justice to the sponge bioherm that only exists in this one small pocket of the world.

“People ask me why we put ourselves through all that, and the risks you’re taking,” added Hamish. “For the last eight years our team’s goal is to bring that unseen realm back with us to share it with the rest of the world. These ancient and unbelievably rare animals need our help.”

Our hope with the documentary, Moonless Oasis, is to raise awareness of glass sponge reefs and encourage more people to care about their fate. If we don’t document these sites, it will be almost impossible to protect them. There is still so much we don’t know about the ocean and the glass sponge reefs are a prime example of this. Sponge reefs could once be found throughout the world’s ocean. The Howe Sound glass sponge reef is a rare remnant of that. On a personal level I hope this shows what can be done by anyone who is passionate and determined enough to protect the natural treasures of their homeland.

Stills courtesy of Nate Slaco, Bryce Zimmerman and Hamish Tweed.

Learn more about Nate Slaco’s film, Moonless Oasis: