Winners, losers emerge amid climate shift in B.C.
Seafood lovers might want to put away recipes for salmon in favour of sardines
A new study from UBC analyzed more than 1,000 aquatic species for vulnerability to the effects of climate change, and the news for three B.C. food fish is not good. William Cheung — an associate professor at the Institute for the Oceans and Fisheries — brought together biological data relevant to adaptability and applied “fuzzy logic” to the computations. The exercise identified 294 marine species worldwide that are most at-risk due to climate change by 2050. Here are some highlights for species native to B.C. waters: LOSER: Sockeye salmon are relatively large fish that are strongly affiliated with specific spawning grounds, fresh- and salt-water habitats, which limits their ability to adapt. They are unable to simply move to find better conditions. LOSER: Pacific coho share many of the limitations of the sockeye and, like the sockeye, they have a longish life cycle. Physiologically, they are suited to a very narrow band of temperatures. Pinks, on the other hand, seem to benefit from warmer water and may already be outcompeting their salmonid cousins. LOSER: Surf smelt were an important commercial fish a century ago until fishing pressure reduced their numbers. Smelt is an estuary species, living in shallow waters that are subject to dramatic change. While some fish can seek deeper, cooler water, that option is not available to the smelt. WINNER: Pacific sardine are a small, fast-growing fish with a really high turnover rate, which aids their ability to evolve in the face of changing conditions. Sardines also have a wide natural range, so they can move to more favourable conditions.
WINNER: California anchovy are similar to sardines in size and have a fast life cycle. Both may actually thrive in the future, taking advantage of changing conditions and exploiting available resources, especially where other species are suffering.
Footnote: The study placed Pacific bonito and green sturgeon among the top five most vulnerable fish in B.C. waters (losers) and includes Pacific sand dab, Pacific sandlance and neon flying squid among the five most adaptable (winners).