Climate change is a significant threat to glass sponge reefs
According to new UBC study, warming ocean temperatures and acidification significantly lower the skeletal strength and filter-feeding ability of glass sponges.
From the Alaska-Canada border and down the Georgian Strait, the reefs play an important role in the quality of water by removing microbes and circulating nutrients across food chains. They also provide vital habitat, including rockfish, spot prawns, herring, halibut and sharks, for many fish and invertebrates.
While the reefs are subject to significant, scientists know little about how these sponges respond to changes in the environment.
"Glass sponge reefs are 'living dinosaurs' thought to have been extinct for 40 million years before they were re-discovered in B.C. in 1986," said Angela Stevenson, who led the study as a postdoctoral fellow at UBC Zoology.
Stevenson collected Aphrocallistes vastus, one of three types of reef-building glass sponges, from Howe Sound for the study and took them to UBC where she conducted the first successful long-term laboratory experiment involving live sponges by simulating as closely as possible their natural environment.
Within a month, ocean acidification and warming, decreased the filtering capacity of the sponges by more than 50 per cent, resulting in tissue losses of 10 to 25 per cent that could starve the sponges.
"In Howe Sound, we want to figure out a way to track changes in sponge growth, size and area and area in the field so we can better understand potential climate implications at a larger scale," said co-author Jeff Marliave, senior research scientist at the Ocean Wise Research Institute.
Maritime Business World