A conservation group is calling for the government to protect a particular kind of reef unique to B.C., following a recent study that shows the “serious and immediate threats” posed by climate change and competition from the commercial fishing sector.
Canadian Parks and Wilderness Society-British Columbia is asking for the establishment of Marine Protected Areas for the province’s glass sponge reefs, a fragile reef that provides vital habitat for all kinds of marine animals within the Hecate Strait, Southern Strait of Georgia, Chatham Sound, and Howe Sound.
Bottom-contact fishing closures have been in place since 2015 for nine reefs in the Georgia Strait. With the discovery of five new reefs in Howe Sound last year, Fisheries and Oceans Canada (DFO) also created eight new marine refuge areas.
But Ross Jameson, the society’s ocean conservation manager, said these closures can theoretically be lifted at anytime by the current or future fisheries ministers, and it’s time to give the reefs the permanent protection of MPA designation.
“Marine Protected Areas will not only protect glass sponge reefs from physical damage caused by bottom-contact fishing, they will also act as natural climate solutions,” Ross said.
“Canada recognizes that we have something unique and vulnerable on our hands, and the government has shown it really wants to be the champion of protecting them … because they just aren’t found anywhere else in the world. We have seen some really good initiative and we want to see them keep up the momentum.”
B.C.’s glass sponge reefs provide critical habitat for 87 forms of sea life, including rockfish, prawns and herring. The filter feeders also play an important role cleaning the water of microbes and particles, while scrubbing the ocean floor of organic carbon at rates similar to old growth forests.
According to University of British Columbia research released last month, it’s estimated the 19 known reefs in the Salish Sea filter 100-billion litres of water each day, removing up to 90 per cent of bacteria from their surrounding waters.
The study, led by Angela Stevenson, a postdoctoral fellow at UBC Zoology, demonstrated ocean acidification and warming can have an immediate effect on the reefs’ pumping capacity, and contribute to irreversible tissue withdrawal and weakening of skeletal strength. In lab studies, 50-60 per cent of sponges ceased pumping within one month of gradual exposure to water warmed by 1.8 C, the estimated sea-temperature increase by 2100.
Further environmental data suggests irreversible damage is possible at just 0.5 C above current conditions.
Glass sponge reefs were thought to have been extinct since the Jurassic period until their rediscovery off Haida Gwaii in 1987. These four reefs, 9,000 years old and covering 1,000 square-km, are the largest known examples and were given MPA clasification in 2017.
Some commercial fishing groups were critical of the decision, saying they fully supported the classification but the size of the area in which fishing was prohibited, almost 150 per cent larger than the reefs’ actual footprint, took away important fishing grounds.
In an email response to Black Press Media, DFO didn’t comment on whether the reefs were under consideration for MPA classification, but noted such a move will require wide-spread consultations first.
“Any future decisions on protection measures for these reefs will be guided by DFO policies and legislation … Any decisions will factor in conservation objectives, an ecosystem-based approach, socio-economic considerations, the input and feedback from the Province, First Nations communities, as well as the views and interests from commercial and recreational harvesters, and other interest groups.”
Ross said he encourages more government-led conversations between all interest groups.