Inside Stories

The difference between kelp and rope

Cetacea Lab: A Voice For Whales

Words by Janie Wray

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Janie Wray and the CetaceaLab have witnessed the comeback of the humpback whale along the coast of Canada’s Great Bear Rainforest. From 42 individuals in 2004, whale numbers have swelled to 335 in the lab’s latest survey.
Photo by Thomas P. Peschak

Cetacea Lab is a whale research facility nestled among the giant red cedars of Gil Island on the remote northern coast of British Columbia, Canada. Surrounding Gil Island are two deep channels known as Whale and Squally. Both names describe this habitat perfectly: the first reflects the boom in the humpback population while the second tells of winter gales that keep boat traffic to a minimum. We built this station more than a decade ago and at the time had no idea that our arrival would coincide with the return of the great humpback whale after years of hunting that ended in the late 1960s.

During our first surveys in 2004 and 2005 we documented 42 individual humpback whales. This number doubled in just four years and by the end of 2014 it had climbed to 335. The nutrient-rich habitat of this stretch of coast is becoming an increasingly important feeding ground for mothers, calves, juveniles and old adults that have seen change come and go. From early spring until mid-summer the most common foraging behaviour observed here is bubble-net feeding. The same whales meet year after year and together they perform an underwater spiral dance of cooperative and bubble-producing movements that force schools of herring from the depths of the ocean to the surface. In a feeding frenzy, giant gaping mouths consume tonnes of fish and krill each day. This dance is repeated over and over in a marathon that lasts from dusk till dawn for weeks on end. As spring becomes summer, the urgency to replenish fat cells after months without food diminishes and we begin to witness more social and robust activities between humpback whales.

Although we continue to share the good news of the return of the great humpback whale to the north coast of British Columbia, it comes at a price. The incidence of these gentle giants accidentally becoming entangled in fishing nets and crab and prawn gear is rising at an alarming rate and along this coast there is no real action plan in place to deal with the problem. More than half the entanglements occur around a humpback’s tail; second and third most frequent are those around the mouth and pectoral fins. When a humpback whale becomes entangled in fishing gear, serious infection can occur from flesh wounds caused by ropes rubbing tightly against its body. These ropes can bind the whale’s long pectorals to its sides and then, unable to move or dive to feed, the giant faces a long and torturous death by starvation. Sometimes the gear is wrapped around its head, with the same result.

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Janie Wray Project Leader - Founder of the North Coast Cetacean Society (NCCS)

Hermann Meuter Project Leader - Founder of the CetaceaLab

In Alaska and along the east coast of Canada and the USA it has been documented that more than 70% of the humpback population bear scars from entanglement, indicating that the whales have had close encounters with ropes or nets at some point in their lives. This also suggests that the way to deal with this increasing problem is to prevent the entanglement from taking place. Along the coast of British Columbia the two most common sources of cetacean entanglements are gill nets and crab or prawn pots. Many humpbacks become caught up in the vertical ropes that connect the pots on the ocean floor to buoys on the surface. The pots are also attached to each other by means of horizontal ropes. These lines are hazardous for humpbacks, which can ensnare themselves while feeding in the depths with their mouths open. But this, I believe, is not the only danger.

It was during an early morning survey that I caught a glimmer of insight from the playfulness of a juvenile humpback we call Ivory. It was just a few hours after sunrise – not that you would have known, as the fog was so thick it was impossible to see more than a few metres into the distance. Personally, I love these days on the water. Travel is extremely slow; I stop and listen for blows, then move forward again at just three to five knots. If I hear a blow, I turn everything off, pour a cup of coffee from my thermos and, with patience in my heart, sit and wait for the day to present itself. The fog usually burns off by 1 pm, creating a magical encounter between me and the majestic Great Bear Rainforest. With every moment the surroundings become clearer, revealing the connection between land and sea in a different light.

On this day I was sitting close to a large kelp bed wrapped around a tiny little rock island when I heard a blow. I could see movement in the kelp bed as it rose and fell. Then something very white, bumpy and long began to emerge. Long amber ribbons of kelp hung from what I now recognised as the pectoral fin of a humpback whale. Curiosity now had me and I moved closer, not really sure what was happening. Was the whale in trouble? It took a few minutes, but I soon realised that this young whale was actually playing in the kelp! Rolling and rolling, wrapping the long stems around its body, then moving to a new patch. I imagine that the rub of these cool, solid structures along the whale’s body must have felt like a giant back massage – the kelp spa for whales!

Then the light bulb came on and I made the connection. Is this what attracts humpback whales to the vertical lines that link rows of crab pots to the surface? Are they going in for a kelp roll or back scratch, not knowing the difference between the harmless benefits of kelp and the deadly power of man-made ropes, inches thick and impossible to break through? In that moment my heart broke; how could the innocence of such playful behaviour have the potential to end so tragically? This is just one small piece of a giant puzzle, but it’s another important clue to finding a way to protect these majestic animals.

Along the east coast of the USA the development of fishing gear and practices that are less likely to entangle a whale is becoming mandatory. For instance, the numbers of vertical lines in areas of high humpback abundance are to be reduced, and there are now restrictions on where and how gear is set and the number of traps or pots per line. One great example is the sinking of lines between prawn traps, so that instead of floating they lie on the ocean floor and cannot get in the way of a feeding whale. This presents problems, though, for fishermen in areas where the sea floor is rocky because over time the ropes may break from rubbing on the rocks. Another requirement is that the line attached to a buoy or flotation device must have a weak link so that an entangled whale is able to break free. In Australia many entanglements occur because floating buoy ropes are extremely long; when lobster fishers move traps from deep offshore waters to shallower inshore waters they neglect to shorten the retrieval buoy line. Shortening excessive rope immediately decreases the chance of entanglement. Changes such as these can also save fishermen the costs associated with the loss or destruction of their gear.

Unfortunately none of these regulations or practices are in place along the coast of British Columbia and the conversation to implement such changes needs to begin now. A few years ago a humpback swam right past the lab with a gill net wrapped around its head and dragging a 15-metre cork line behind it. It took 24 hours and an entire community working together to save this whale, but in the end we succeeded. The support that we received from local people on that day gives me great hope. There is no doubt that, as the population of humpback whales continues to increase, we need to work together with those who make a living from the marine resources of the British Columbian coast and take collective responsibility for the safety of whales. No creature on this planet deserves to suffer a long and tragic death when there is the potential to avoid it.