Underwater gardeners are working to restore BC’s majestic kelp forests

In the cold waters of Barkley Sound on Vancouver Island, gardeners work on the seabed.

They are Victoria University scientists trying to recreate kelp forests, a crucial part of the marine habitat, amid threats from heat waves, climate change and voracious sea urchins.

Julia Baum, a professor of ocean ecology and global change at the University of Victoria, studied data going back decades about BC’s majestic underwater forests, which provide food and resources for fish and other coastal organisms.

She said “a very prolonged marine heat wave between 2014 and 2016” had a major impact on the northeast Pacific.

“And what we found was that in several places, the kelp forests were gone,” Baum said.

Bull kelp and giant kelp are the two main canopy-forming kelp species found in marine habitats off the west coast of Canada.

“We found that both disappeared in areas that got really anomalously warm during this long, prolonged heat wave,” Baum said.

The achievement determined the ongoing project on the restoration of kelp forests.

The four-year project, funded with $3.68 million from Fisheries and Oceans Canada, is now in its second year, with researchers teaming up with British Columbia coastal First Nations to grow kelp in Bamfield nurseries on Barkley Sound.

But the science of algae restoration is still in its infancy, Baum said.

Unlike vegetative plants that root in the soil, kelp instead uses a structure called a “hold” to attach itself to rocks.

She said her group experimented with planting young algae on various materials, such as different-sized rocks or gravel, “to try and see what would do best.”

Reforesting the ocean floor with algae is “hard work,” she said, with divers having to plant the algae, monitor its growth and measure its resilience under different conditions.

“So these are really large-scale manipulation experiments where we plant algae. It’s kind of replanting a forest, reforesting an area,” she said.

A statement from the university said collaborators include the Huu-aye-aht First Nations and other First Nations, the Marine Science Society of Western Canadian Universities, the Pacific Salmon Foundation, Genome BC, the Hakai Institute, West Coast Kelp and other groups.

Connie Crocker, the project’s First Nations liaison, built relationships between scientists and First Nations to apply Indigenous knowledge and expertise to the kelp restoration project.

“The road map to algae recovery is through awareness. It’s all about awareness – there’s strength in numbers,” she said in the statement.

“We need the public behind us… it’s urgent and the ocean is in danger. If people knew about the algae decline, we could make some progress.”

Baum said the project was urgent and that he felt “the push and the drive” to protect the kelp forests.

“Restoration projects often take a very long time to be successful because it’s hard work,” she said.

“But we’re approaching it in a really rigorous scientific way, and so I’m hoping we can make good progress and make a difference to our coastal kelp forest ecosystems.”

This report by The Canadian Press was first published on July 1, 2024.

Nono Shen, Canadian Press