In the Wild
Researchers from Memorial University in St. John’s, N.L., helped write a new study that looks at how different animal species influence the carbon cycle. Here are a few Canadian animals that perform essential carbon cycling roles.
Three-spined stickleback | EAST COAST Great horned owl; striped skunk In the freshwater ponds and streams where they’re found, sticklebacks interrupt the carbon cycle by eating zooplankton and other tiny critters that eat algae, which would otherwise photosynthesize away some of the carbon dioxide produced by decaying material in these bodies of water. More sticklebacks mean fewer predators eating algae — and therefore less CO2.
Brent geese | ARCTIC Like the stickleback, brent geese have evolved relationships with their environment that affect the emission of CO2 and other greenhouse gases. In their case, it’s not because of hunting: brent geese are herbivores, and the plants they eat would otherwise decay, releasing greenhouse gases in the process.
Two-striped grasshopper | PRAIRIES As the case of the grasshopper shows, animals can also cause more greenhouse gases to be released into the atmosphere. Grasshoppers eat grasslands plants, sequestering CO2 just like the geese: but their predators, spiders, are responsible for completely reversing the sequestering impact of the grasshoppers. This isn’t a zero-sum game, though: biodiversity generally is responsible, in part, for keeping emissions under control in intact environments.
Cougar | ROCKIES As with the spiders, cougar predation on herbivores such as elk can contribute to CO2 production. But without predators, the herbivore population would grow uncontrolled, causing die-offs and instability that would also contribute to greenhouse gas production.
Sea otter | COASTAL B.C. Some predators, like the sea otters of coastal British Columbia’s underwater kelp forests, help their environment keep carbon from getting to the air. By simply enjoying sea urchins, their favourite food, the otters help out the kelp, which in turn takes in carbon. Left unchecked by the sea otters, urchins quickly munch their way through kelp forests.