Early last week, a study from a group of universities, research centres and environmental groups in the United States pointed out a broadening danger for commercial fisheries in 15 states, 14 of them on the Atlantic coast.
The study, by scientists with the University of California at Davis, Duke University, the Natural Resources Defence Council and the Ocean Conservancy, says that the rapid acidification of the planet’s oceans now poses direct threats to the scallop, clam and oyster industries in California and right up the Atlantic coast, growing more severe as you move northwards.
(The potential threat would be a lot easier to discount if ocean acidification in the Pacific Ocean wasn’t already showing clear commercial effects; acidification there has damaged spawning and cost the Pacific oyster industry some US$110 million.)
The problem is that many species, from plankton on up, are built around calcium carbonate: higher acidity in the ocean affects calcium carbonate formations, but also affects everything from marine species’ ability to reproduce to their ability to shed carbon dioxide from their muscle tissue. There’s been plenty of research on the nuts and bolts of ocean acidification, but less on its direct effects on species.
Some things are known.
The success of spawning cod is known to be affected by ocean acidity. As well, primary food sources for commercial species are at risk. Almost every Atlantic Canadian commercially harvested crustacean and mollusk is on the list of organisms that face risks. The food sources of those commercial species are likely to be affected even more harshly.
“Laboratory experiments demonstrate that early life stages of large, calcifying marine organisms, including echinoderms (e.g., starfish, brittle stars, sea urchins and sea cucumbers), bivalves (e.g., scallops, mussels, clams and oysters), crustaceans (e.g., lobsters, crabs, shrimp and krill), and corals are vulnerable to ocean acidification during the fertilization, cleavage, larval settlement, and reproduction stages,” according to fisheries research published in the journal Marine Ecology in 2008.
But if it’s bad along the coastal U.S., the dangers in Atlantic Canada run higher.
Here, the species affected are worth billions in landed value every year, and, to add to the damage, colder water in the North Atlantic seems to be absorbing atmospheric carbon dioxide — and getting more acidic in the process — even faster than other regions:
“The North Atlantic, with its exceptional capacity to uptake atmospheric carbon dioxide, will likely see greater rates of ocean acidification relative to other ocean basins, especially as its ability to buffer future carbonic acid formation is continually reduced through time,” DFO science from 2012 points out.
(To put that “exceptional capacity” in context, the North Atlantic is 15 per cent of the surface area of the world’s oceans, but has taken in 23 per cent of the carbon dioxide absorbed by those oceans.)
The bottom line? The fishing and aquaculture industry may quickly learn what insurance companies already know about climate change and carbon dioxide emissions: the end result of continuing to pollute has clear, identifiable business costs. For the insurance industry, it’s the cost of more frequent — and more violent — storms. For crucial Atlantic fisheries, it’s the potential for fewer and weaker fish species. And it’s not the heartiest of industries already.
Russell Wangersky, Journal Pioneer, 2 March 2015. Article.
