Scientists are now struggling to predict the marine winners and losers, so they can work out food web, fisheries and ecological implications. Already, it looks like the killer whales will be one of the losers. Studies show that acidification will likely impact killer whales by disrupting the echolocation they use to navigate and find prey, by altering the way sound is absorbed under the sea. More dangerously, as the ocean grows more acidic, their food sources will be threatened. Killer whales eat chinook salmon, and the salmon in turn eat tiny pteropods or “sea butterflies.” And “unless pteropods can develop protective mechanisms to prevent shell dissolution within this century, they will not fare well in the future,” says Victoria Fabry, the world’s leading pteropod expert, who spoke to Maclean’s from a research station in French Polynesia.
Ocean acidification is “essentially irreversible” during periods measured in mere decades, according to Britain’s Royal Society. Its effects, however, will not begin to be felt until mid-century. So there is some hope that tiny sea organisms will adapt to the rising acid levels. Many of them multiply several times every day, so they will have some 50,000 generations to adapt to mid-century conditions. Other zooplankton, however, can live multiple years, so it’s not yet clear whether there is enough time for them to evolve. In geologic terms, a quick change occurs over 10,000 years, but the acidification of the oceans appears to be happening over a period of 50 to 100 years.
Still, that may be enough time to avoid the impending catastrophe. Out on the water in the zodiac, Peter Ross from the Department of Fisheries and Oceans points to an example that proves how successful we can be when we do act. It’s an elephant seal and her brand-new pup—no more than five days old, by his estimate. He notes that the seals were once reduced to just 27 individuals, but now number more than 100,000. They’re moving into B.C. waters, and in February, the province recorded its first birth. Nearby, gulls have formed a frenzied, squawking cloud indicating a “herring ball”—when the fish form a tight, defensive ball near the ocean surface. From here, it is hard to believe something so deeply wrong may be brewing beneath us.
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