Members of DFO’s Marine Mammal Rescue are chalking up an incident this week as a win even though they didn’t have to do anything when they arrived on scene.
Paul Cottrell, fisheries biologist and coordinator for the Department of Fisheries and Oceans’ Marine Mammal Rescue, and his team members responded Sunday at about 5 p.m. after they received a call to help free a juvenile killer whale entangled in the line of a prawn trap just off Rocky Point in north Nanaimo.
The young whale dragged the line and trap for about 600 metres and was struggling to free itself.
Boaters nearby called the DFO whale rescue unit and stayed back and observed until help arrived.
“What happened initially was the big killer whales were foraging and consuming and tenderizing a harbour seal right where the buoy [for the trap line] is and near the end of the kill, unfortunately one of the juvenile killer whales got caught up in the rope there,” Cottrell said.
The orca managed to get itself untangled shortly after the DFO team arrived on scene.
“They don’t always get out themselves,” Cottrell said. “I’ve been involved in quite a few rescues over the years … where animals were stuck.”
Cottrell said no two entanglements are alike. Depending on the whale’s struggles, trap lines can wrap around their tails multiple times or become caught up in the animal’s mouth, pectoral fins and tail so the whale becomes effectively hog-tied and unable to move. If a whale can’t get to the water’s surface it can drown.
Some animals get tangled up more often than others.
“I think they’re very aware of their surroundings, killer whales, but I think it’s often curiosity too,” Cottrell said. “There are a couple of animals that are renowned for interacting with ropes and floats and lines … One of the animals we rescued a number of [times] was an animal that has a bad habit of doing that and … every year, this one particular animal we get three or four calls … he’s quite a character.”
Because of their smaller size, orcas don’t have the stamina of whales with greater body mass that can actually drag fishing gear for very long distances, sometimes for months, so it’s important that help comes quickly.
“We’re basically a kind of SWAT team, ready to respond at any time,” Cottrell said. “I have kit with me all the time because it’s a priority in my job to be able to respond to entangle animals, so it’s kind of cool and I love it.”
Research is being conducted in Canada and the U.S. to design rope-less fishing gear or release mechanisms to prevent entanglement, but there are ways to help avoid it which include using tether lines that sink to the ocean bottom or lines that limit slack for a whale to wrap itself up in.
“If you have too much loose line an animal can easily get wrapped around there and they’ll interact with the line, maybe deep where they don’t see it and if they panic and roll, they get it around their tail stock and they’re screwed,” Cottrell said.
He said the people who called his team for help did the right thing by staying back from the whales and observing until help arrived.
“You really have to be careful when you come on scene to really assess before you start cutting, because if you make the wrong cut you can actually make things worse for the animal,” he said.
Anyone who spots a whale stranded on the shore, entangled in fishing gear or otherwise in distress is asked to report the incident immediately to the 24-hour DFO marine mammal incident hotline at 1-800-465-4336.