Glass Sponge Reefs: a New Opportunity for Conservation Research

OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

Glass Sponge Reefs: a new opportunity for conservation research

AUTHOR Jeff Marliave, Ph.D., Senior Research Scientist, What’s happening with Howe Sound Research Group, Coastal Ocean Research Institute, Vancouver Aquarium Marine Science Center glass sponge reefs? REVIEWER Lena Clayton, B.Sc., Researcher, Marine Life In 2015, Fisheries and Oceans Canada (DFO) closed bottom contact fishing Sanctuaries Society (i.e., all commercial and recreational bottom contact fishing activities for prawn, shrimp, crab and groundfish, including halibut, were prohibited) at nine glass sponge reefs in the Strait of Georgia, including reefs surround- ing Passage Island at the entrance to Howe Sound, and at Defence Islands northeast of Anvil Island.1 During the process leading to those closures, citizen scientists Glen Dennison and Lena Clayton were actively using a new method of drop-camera drift transects to identify locations of glass sponge reefs in Howe Sound (Figure 1). These newly identified Howe Sound sponge reefs were not considered during that earlier federal process, so they remain unprotected, with the exception of the Passage Island sponge reefs.

Photo: Adam Taylor

Glass Sponge Reefs | Page 116 OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

Therefore, citizen scientist divers, dive industry rep- ages of the sponges together with these location iden- resentatives (guides, instructors) and the Vancouver tifier stakes, in order to allow monitoring of sponge Aquarium’s Howe Sound divers met in May 2015 to growth and health over time at this site. discuss approaches to protecting these Howe Sound sponge reefs. In an about-face on previous secrecy In late May, the annual prawn fishing season took about reef locations in order to protect sponges from place, with many observations of fishing on Howe accidental anchor damage, it was decided to go public Sound glass sponge reefs noted by conservationists. and invite citizen science divers on the reefs to gain The fishery closed earlier than planned in 2016 owing public awareness. With a grant from Mountain Equip- to low catch rates. The greatest human conflict with ment Co-op (MEC), the Vancouver Aquarium Marine glass sponge reefs relates to fishing gear damage to Science Centre developed a web page2 showing citizen the reefs,3 whether from downrigger contact, bottom science divers how to locate and photograph or video- trawling or prawn trap contact, and has been the basis tape various bar-coded stakes around the periphery of for almost all the negotiated closures with fishing the inshore Defence Island bioherm, then submit im- sectors for the sake of sponge reef protection.

Photomural of offshore Defence bioherm at 100 feet depth. Eight photos taken by Jeff Marliave in August of 2004 and merged using Photoshop.

Is there a particular importance or connection to First Nations?

The Defence Islands are sacred to the Squamish Na- in seeing conservation of the glass sponge reefs off the tion, and the Squamish Nation has indicated interest eastern Defence Island.

Glass Sponge Reefs | Page 117 OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

Figure 1. Pink dots indicate glass sponge reef locations in Howe Sound determined by drifting drop-camera method of Glen Dennison and Lena Clayton (personal communication). The four southern-most reefs are located inside a DFO closure implemented in 2015. The green shading represents the approximate area of Squamish River and Fraser River outflows in Howe Sound.

Glass Sponge Reefs | Page 118 OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

Why is it important?

Glass sponge reefs (also called bioherms) were glass sponge species in Howe Sound. The cloud name thought to have gone extinct thousands of years ago4 comes from its appearance. when they were discovered off the Canadian continental shelf in the mid-1980s.5 Howe Sound is the only These glass sponge reefs provide refuge for rockfish known location where these glass sponge reefs are broodstock,6,7 and in Howe Sound the redstripe rock- shallow enough to be studied by scuba divers using fish is a species almost exclusively associated with compressed air, making them uniquely accessible to these reefs. Spot prawns aggregate around the sponge the diving community. Cloud sponge is a common reefs, and for that reason the conflict with prawn name for Aphrocallistes vastus, the main reef-forming trapping activity arises.

What is the current state?

“Local knowledge” about cloud sponges differs de- that accumulate around the periphery of the reefs. pending on who you talk to. Fishermen have long said Whereas the Pacific cod trawl fishery in the Strait of of cloud sponges, “oh, yeah, that’s sea cabbage, and Georgia eliminated large areas of glass sponge reef on it grows back the next winter.” In contrast, divers Halibut and McCall Banks, the prawn trap fishery has had the lore that cloud sponges are hundreds of years caused more localized damage, which may experience old and never grow back if damaged. The truth is that healing and recovery during favourable climate cycles. there appears to be a tendency for individual sponges to grow at varying rates during different climate Monitoring is needed to determine the extent to which cycles. Deterioration has been observed during the sponge reefs can heal damage caused by climate cycles buildup of El Niños (warm coastal winters) and rapid or mechanical damage by humans. The dive volun- episodic growth was observed in some sponges during teers posting on the Aquarium website for the bar code La Niña cycles (cooler winters). In 2015, the first proof marked areas at the inshore Defence Island location of fragment healing and reattachment in cloud spon- have already documented that necrosis of a head of ges was published;8 notably, healing took place during cloud sponge can occur within several months.10 La Niña weather.

Mechanical damage to sponge reefs in Howe Sound has been documented in the video transects of Glen Den- nison.9 The prawn fishery has focused on fishing near these reefs because of the high densities of prawns

Glass Sponge Reefs | Page 119 OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

What’s being done?

In October 2016, seven organizations11 submitted a Salish Sea Ecosystem Conference in Vancouver in proposal to Fisheries and Oceans Canada asking for April 2016, there were four presentations on the glass protection of the glass sponge reefs in Howe Sound. sponge reefs of Howe Sound, covering various aspects The Regional Director General for the Pacific Region of the biology, ecology and conservation of these reefs. responded suggesting that the detailed information Between these March and April meetings and the May provided on the Howe Sound Sponge Reefs would feed announcement of inclusion of the sponge reef near directly into the marine conservation target strategy Halkett Point inside the new boundaries of Halkett of establishing new effective area-based conservation Marine Park, there has been favourable publicity of measures, such as closing fisheries in waters that are these reefs. On May 31, the David Suzuki Foundation home to sensitive sponges and corals. and Vancouver Aquarium hosted a public meeting at Kay Meek Centre featuring Howe Sound videos, in- Diving representatives approached BC Parks to discuss cluding a sponge reef video by Roy Mulder. possible expansion of Halkett Bay Marine Provincial Park on Gambier Island, to include the Halkett pin- A new federal process for protection of Howe Sound nacle sponge reef. On May 26, 2016, the B.C. Minister glass sponge reefs under the federal Pacific Region of Environment, Mary Polak, announced the expan- Cold-Water Coral and Sponge Conservation Strategy,12 sion of Halkett Bay Marine Park to include the sponge which was released in 2011, is being urged for Howe reef. Future plans are for funding a safe, permanent Sound. Requests are now being promulgated. boat moorage for divers’ access to that sponge reef. Citizen science will be enhanced owing to the access- Divers need to exercise caution to avoid breaking ibility of this reef at Halkett Point to commercial dive sponges by contact with fins or hands, so a new Pro- charters out of Horseshoe Bay. fessional Association of Diving Instructors (PADI) course has been developed to teach safe diving prac- On March 23, 2016, Canadian Parks and Wilderness tice around sponge reefs. Society (CPAWS) hosted an evening at Science World on glass sponge reefs, which included discussion of the Strait of Georgia and Howe Sound reefs. At the

Glass Sponge Reefs | Page 120 OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

Glass sponge reef home to juvenile rockfish. (Photo: Adam Taylor)

What can you do?

Individual and Organization Actions:

• Contribute to citizen science projects in order to monitor glass sponge growth at the inshore 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 Howe Sound, specifically if bottom contact fishing or mooring your vessel.

Government Actions 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 Howe Sound. • Support local citizen science projects, and formal studies aimed at understanding and monitoring glass sponge reefs. • Install a safe and permanent moorage for dive boats at glass sponge reef sites. • Implement full protection of glass sponge reefs throughout all of Howe Sound. • Restrict bottom contact fishing throughout all glass sponge reefs in Howe Sound.

Glass Sponge Reefs | Page 121 OCEAN WATCH | Howe Sound Edition SPECIES AND HABITATS

Resources

Drop camera and other videos of sponge reefs in Howe Sound mlssbc.com/2013/04/27/mlss-collaborates-with- experts-from-vancouver-aquarium/

Footnotes

1 http://www.pac.dfo-mpo.gc.ca/oceans/protection/sponge_reef- 8 Marliave, J. 2015. Cloud Sponge, Aphrocallistes vastus (Porifera: recif_eponge-eng.html Hexactinellida), fragment healing and reattachment. Canadian Field- Naturalist. 129(4):399-402. 2 http://www.vanaqua.org/act/research/howe-sound-group/sponges 9 For examples, see Mulder, R. “Sponge Damage.” Video, June 1, 2015. 3 Kahn, A.S., L.J. Vehring, R.R. Brown, and S.P. Leys. 2016. Dynamic Accessed Sept 19, 2016. https://mlssbc.com/2015/06/08/defence- change, recruitment and resilience in reef-forming glass sponges. island-bioherm-dive-may-31-2015/ and “MLSS Discovers Massive Journal of the Marine Biological Association of the United Kingdom. Sponge Bioherm in Howe Sound.” Oct 7, 2014. Accessed Sept 19, 2016. 96 (2): 429-436. https://mlssbc.com/2014/10/07/mlss-discovers-massive-sponge- 4 Krautter, M., K.W. Conway, J.V. Barrie and M. Neuweiler. 2001. bioherm-in-howe-sound/ Discovery of a “living dinosaur”: globally unique modern 10 Vancouver Aquarium. “Diving Sponge Reefs and Gardens. Accessed hexactinellid sponge reefs off British Columbia, Canada. Facies. 44: Sept 19, 2016. http://www.vanaqua.org/act/research/howe-sound- 265-282. group/sponges 5 Conway, K.W., J.V. Barrie, W.C. Austin, and J.L. Luternauer. 1991. 11 Canadian Parks and Wilderness Society, Marine Life Sanctuaries Holocene sponge bioherms on the western Canadian continental Society, Canadian Marine Environment Protection Society, David shelf. Continental shelf research. 11: 771-790 Suzuki Foundation, Future of Howe Sound Society, Sunshine Coast 6 Marliave, J.B., K.W. Conway, D.M. Gibbs, A. Lamb and C. Gibbs. Conservation Association, and the Vancouver Aquarium Marine 2009. Biodiversity and rockfish recruitment in sponge gardens and Science Centre. bioherms of southern British Columbia, Canada. Marine Biology. 156: 12 http://www.pac.dfo-mpo.gc.ca/oceans/protection/docs/cscs-pcce- 2247-2254 eng.pdf 7 Cook, S.E. 2005. Ecology of the hexactinellid sponge reefs on the western Canadian continental shelf. MSc thesis, University of Victoria, Canada.

Glass Sponge Reefs | Page 122