The Sea of Glass: Protecting BC’s unique glass sponge reefs

Deep in the cold dark waters of the BC coast lie rare ecosystems once thought extinct: glass sponge reefs! While individual glass sponges have been identified around the world, glass sponge reefs are mostly unique to beautiful British Columbia. On the north and central coasts, these living reefs stretch for hundreds of kilometres across the seafloor and reach the height of a six story building. Smaller reefs also grow in the Salish Sea on the south coast, just outside Vancouver and Victoria. BC truly has a sea of glass!

Natural Solution to Climate Change

These marine animals are an integral part of a healthy marine habitat. Glass sponge reefs provide shelter for marine life including rockfish and shrimp, store carbon on the ocean floor, filter bacteria out of the water, and fertilize the ocean. The sea of glass supports thriving culture and livelihoods for coastal communities.

With skeletons made of silica, these sponges are extremely fragile. Bottom contact fishing such as bottom trawling and shrimp trapping easily shatter their bodies. Sediment on the seafloor kicked up by these fishing methods also causes them to “choke” and stop feeding.

ID: illustration of orange rockfish and prawn silhouette by white reef

Glass sponge reefs provide habitat for economically important rockfish and shrimp

ID: White reef tube illustration with purple bacteria moving through with blue arrows

ID: illustration white reef tubes with carbon iicon being absorbed

ID: white reef tubes with 3 amonia icons being expelled

Strong Permanent Protection for the Sea of Glass

CPAWS-BC looks to protect the Sea of Glass by calling on the federal government to ban bottom contact fishing on or near glass sponge reefs with marine protected areas (MPAs) and Other Effective Conservation Measures (OECMs) such as marine refuges and fishing closures.

North and Central Coasts

North and Central Coasts
South Coast

Hecate Strait/Queen Charlotte Sound Glass Sponge Reefs Marine Protected Area

Off the north and central coasts of BC, the Hecate Strait/Queen Charlotte Sound Glass Sponge Reefs Marine Protected Area (MPA) prohibits bottom contact fishing. CPAWS-BC is calling on the federal government to make the MPA bigger because new research shows that sediment from beyond the one kilometre buffer zone, as far away as six kilometres, can cause the sponges to choke.

Strait of Georgia and Howe Sound Glass Sponge Reefs

On the south coast, the marine refuges and fishing closures of the Strait of Georgia and Howe Sound Glass Sponge Reef Conservation Initiative protect the Salish Sea’s glass sponge reefs. While not full marine protected areas, these OECMs prohibit bottom contact fishing. CPAWS-BC is calling on the federal government to make these protections more permanent since the current laws can be removed with a change in ministry leadership. We are also calling for better monitoring and enforcement because after the fact fines do not prevent fishing damage from occurring in the first place.

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