Along the Dallas Road breakwater in Victoria, there is a flourishing abundance of kelp forests beneath the cold waters, as highlighted by Brian Timmer, a PhD student at the University of Victoria (UVic). While these areas thrive due to the chilly water, other regions in British Columbia are experiencing localized warming, resulting in the disappearance of once-thriving kelp forests.
A recent study led by Timmer from UVic, published in Ecological Applications, examined historical data on kelp and its associated macroalgae communities in the northern Salish Sea. By analyzing maps, scuba surveys, and aerial photos dating back to 1972 and replicating these studies in 2023, the research team discovered significant changes in the kelp ecosystem.
The study revealed that the expansive bull kelp forests that once covered over 5.5 million square meters in the northern Salish Sea, particularly around the Comox and Denman Island region, have vanished. This loss is ten times larger than the previously accepted baseline established around 2000.
Contrary to the belief that recent heatwaves, like the “Blob” heatwave from 2014 to 2016, were solely responsible for the disappearance of bull kelp forests in British Columbia, Timmer’s research suggests that the most substantial decline occurred between 1972 and 1984. The study focused on a warm water pocket near Comox and Denman Island, showcasing significant ocean warming trends over the past 50 years.
Kelp, considered a foundation species and primary producer, plays a crucial role in marine ecosystems by providing habitat and sustenance for various sea creatures. The decline in kelp populations, including a 78% reduction in sugar kelp and a 98.5% decline in red bladed algae since 1972, is attributed to the warming waters along British Columbia’s coast.
To address this issue, Timmer collaborates with the Kelp Rescue Initiative and First Nations to restore kelp forests in the province. By identifying suitable areas for kelp habitats and reintroducing kelp species, efforts are being made to protect and revive these vital marine ecosystems.