Near and far, how apex species interact with us—and the ecological changes we have wrought.

Bobcats

Sightings are on the rise, but little is known about bobcats in Southern New England, so two wildlife biologists—professor Thomas Husband and the Department of Environmental Management’s Charles Brown ’85—captured one in November as part of a five-year study.

A tracking collar reveals he’s “wandering a lot farther than we expected: Snug Harbor, Bonnet Shores, Matunuck, Charlestown,” says Brown. “We lose track of him for a few days, but we always catch up to him.”

Bobcats weigh up to 35 pounds and are the most widely distributed feline in North America. In Rhode Island, they are believed to consume mostly rabbits, squirrels and rodents. Hotspots are South Kingstown, Westerly and Foster, but they also travel through densely populated areas of Cranston, Warwick and West Warwick.

It’s turning out to be difficult to trap more of the canny animals. Bait like dead ducks, rabbits and squirrels has failed to ensnare any, although motion-sensor cameras indicate several have investigated researchers’ traps. Other animals are less suspicious: gray foxes, fishers, a red-tailed hawk and several opossums have been released.

Copepods

Calanus glacialis copepods are crustaceans, slightly smaller than a raisin, crucial to Arctic ecosystems. Important food for fish and seabirds, they’re predators themselves—but they’re so tiny that their eating habits can be difficult to study.

Alison Cleary, Ph.D. ’15, spent six months with colleagues at the University Centre in Svalbard, Norway, working on new DNA sequencing tools to figure out what was in the copepods’ stomachs.

The sun doesn’t set during Svalbard’s summer; months of winter darkness follow. Much of the coastal sea is covered in solid ice. So the copepods eat plant-like plankton when there’s enough sunlight for it to grow. In the depths of winter, they fast. In early spring and late summer, they eat animal plankton.

Why care? They play a vital role in a food web that, so far, has been the most stressed by climate change. “Understanding the things Calanus eat under different circumstances has implications for how organisms that eat Calanus, and those even higher up the food chain, will fare,” says Cleary.

Sharks

Makos are among the fastest swimmers in the ocean and travel great distances between feeding grounds. They’re also sought after by fishermen around the world because they taste good.

So biologist Brad Wetherbee teamed up with shark experts in Nova Scotia to establish the Great Shark Race. Businesses and individuals sponsor sharks by buying satellite tracking tags; the researchers trace their paths, and encourage people to follow them online.

The winner, a shark dubbed Ebenezer by its sponsor, entrepreneur Richard Branson, traveled more than 7,000 miles during the race, departing the Maryland coast for the Canadian Maritimes, then racing straight to South America before turning around and coming back.

“Sometimes they go straight for a thousand miles without stopping, then stop and zigzag around,” observes Johann Becker ’17, who studies makos with Wetherbee and won a $19,000 National Oceanic and Atmospheric Administration scholarship in April.

Three of the eleven tagged sharks were killed by fishermen during the six-month race.

Orcas

Most of what is known about killer whales comes from the Pacific Northwest—but they’re also found in the North Atlantic, and Tara Stevens, Ph.D. ’17, is the first to investigate the 200 or so that live around Newfoundland and Labrador.

“We had no idea what they were even feeding on, but it became clear minke whales are a predominant prey,” explains Stevens. “We would see sometimes 10 or 20 killer whales jumping on a minke to force it underwater. Their strategy is to drown them.”

Orcas also eat dolphins, porpoises and seals, and perhaps fish: “We’ve seen some taking halibut and tuna off longlines,” Stevens says. “There used to be a substantial population associated with the tuna fishery in the Gulf of Maine, but the fishery crashed and we don’t know where they went.”

It’s unknown whether orcas in the North Atlantic are prey specialists, like their Pacific cousins, but Stevens says some may be: for instance, those that remain year-round in Newfoundland and Labrador have been sighted within the pack ice, feeding on breeding seals.