Banner Photo: A juvenile yelloweye rockfish over a glass sponge reef. (Credit: Adam Taylor)

2020 Rating

2020 Rationale

Considerable advances in knowledge have been made; however, glass sponges remain vulnerable to mechanical damage and climate change.

2017 Rating

2017 Rationale

Once thought extinct, the discovery of glass sponge reefs in Howe Sound has spurred a flurry of interest in these ancient organisms. Efforts from citizen scientists, divers and researchers have been instrumental in expanding protected marine areas to safeguard this critical fish habitat. Threats remain and research and advocacy efforts are high.

The following is an excerpt from the full updated article. Download the full 2020 article for all content and references.

Glass Sponge Reefs: fragile habitats require further protection

Authors: Jeff Marliave, Senior Research Scientist, Howe Sound Conservation and Research Team, Ocean Wise Research Institute

Aroha Miller, Manager, Ocean Watch, Ocean Wise Research Institute 

Reviewer: Anja Dunham, Research Scientist, Fisheries and Oceans Canada (DFO)

Excerpt from 2020 article

Glass sponge reefs only occur in B.C.’s Pacific coastal waters. Átl’ḵa7tsem/ Txwnéwu7ts/Howe Sound has some of the best, most intact sponge reefs in all of B.C. The reefs in Átl’ḵa7tsem/Txwnéwu7ts/Howe Sound are the only ones that are shallow enough to reach by air diving; all other known reefs occur at much greater depths and require technical diving or use of a remotely operated vehicle (ROV) to access. This aspect alone makes these Átl’ḵa7tsem/Txwnéwu7ts/Howe Sound reefs extremely unique and comparatively accessible.

Read the full article to see what else is happening.

  Edit to 2020 article

Citizen science conducted by the Marine Life Sanctuaries Society (MLSS) was instrumental in the discovery and documentation of glass sponge reefs within Átl’ḵa7tsem/Txwnéwu7ts/Howe SoundIn 2017, MLSS submitted published reports1,2 to Fisheries and Oceans Canada (DFO), providing evidence of nine newly discovered, unprotected sponge aggregations on the east side of Átl’ḵa7tsem/Txwnéwu7ts/Howe SoundThe MLSS documentation identified biological significance (biodiversity, ecological services, and community composition) in support of the DFO assessment of these reefs.3,4 As a result of this work, and work by other conservation groupseight Marine Refuge Conservation Areas were established in April 2019. 

In May 2019, nine additional suspected sponge reef aggregations on the west side of Átl’ḵa7tsem/Txwnéwu7ts/Howe Soundseveral mapped by MLSS, were surveyed and ground-truthed by DFO. Five of these reefs are currently awaiting protection approval.5 MLSS continues to report infractions to DFO of increased poaching for fish and prawns on these reefs. 

1. Clayton, L. and G. Dennison. 2017. Inexpensive video drop-camera for surveying sensitive benthic habitats: applications from glass sponge (Hexactinellida) reefs in Howe Sound, British Columbia. Canadian Field-Naturalist 131(1): 46-54. 

2. McAuley (Tryon), L. 2017.Howe Sound Glass Sponge Reef Identification. Report on behalf of MLSS to DFO. 39 pp. 

3. DFO. 2018. Glass sponge aggregations in Howe Sound: locations, reef status, and ecological significance assessment. DFO Canadian Science Advisory Secretariat Science Response 2018/032 43 pp. 

4. Dunham, A., Archer, SK., Davies, SC., Burke, LA., Mossman, J., Pegg, JR., and Archer, E.  Assessing condition and ecological role of deep-water biogenic habitats: glass sponge reefs in the Salish Sea. Marine Environmental Research. 141: 88-99. 

5. DFO. 2020. Ground-truthing the latest set of suspected glass sponge reefs in Howe Sound: Reef delineation and status assessment. DFO Canadian Science Advisory Secretariat Science Response 2020/026 28 pp. 

Read the full article here.

Background: A quillback rockfish on a glass sponge reef, Ḵw’émḵw’em/Defense Islands. (Credit: Adam Taylor)

What’s been done since 2017?

The table below reports on progress made on recommended actions from the previous 2017 article, where identified. Many of these require ongoing action.

2017 Action Action Taken
Individual and Organization Actions
Install a safe and permanent moorage for dive boats at glass sponge reef sites. The Marine Life Sanctuaries Society (MLSS) and partners have installed the base of what will be a permanent mooring buoy at the Halkett Marine Park sponge reef at Halkett Pinnacle. This will provide safe moorage and safe access for divers to the sponge garden on a ridge contiguous with the deeper sponge reef. Citizen science documentation of that garden and reef is anticipated, with the cooperation of commercial dive boat operators, and with web data reports and scientific assistance from Ocean Wise Research Institute, similar to the Annapolis Reef in Halkett Bay.
Government Action and Policy
Implement full protection of glass sponge reefs throughout all of Átl’ḵa7tsem/Txwnéwu7ts/Howe Sound. In March 2019, DFO announced the closure of the nine documented glass sponge reef complexes in Átl’ḵa7tsem/Txwnéwu7ts/ Howe Sound to bottom-contact fishing with the establishment of eight distinct Marine Refuges. Furthermore, nine additional possible reef sites in Átl’ḵa7tsem/Txwnéwu7ts/ Howe Sound were mapped in the DFO report3 that preceded the public review process. Those sites have since been surveyed in a DFO ROV research cruise in May 2019; publication of results is anticipated in 2020. 

What can you do?

A detailed overview of recommended actions relating to climate change is included in The path to zero carbon municipalities. In some cases, no progress was identified on previous recommended actions; these remain listed below.

action-individual Individual and Organization Actions:

    • Contribute to citizen science projects in order to monitor glass sponge growth at the inshore Ḵw’émḵw’em/ Defence Island sponge reef.
    • Report illegal fishing and trapping to DFO within sponge closure areas.
    • Take the padi course developed to teach safe diving practice around sponge reefs before diving around sponge reefs.
    • Familiarize yourself and others with locations of sponge reefs throughout Átl’ḵa7tsem/Txwnéwu7ts/Howe Sound, specifically if bottom contact fishing or mooring your vessel.

action-governmentGovernment Action and Policy:

    • Encourage local education and awareness of the importance of sponge reefs, and the risks they face.
    • Advertise the uniqueness of the opportunity to dive a sponge reef using compressed air in Átl’ḵa7tsem/ Txwnéwu7ts/Howe Sound.
    •  Support local citizen science projects, and formal studies aimed at understanding and monitoring glass sponge reefs.
    • Restrict bottom contact fishing throughout all glass sponge reefs in Átl’ḵa7tsem/Txwnéwu7ts/Howe Sound.
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