…but the Old Neighbourhood has Changed
Among the whale watching community in British Columbia, the summer of 2016 has become known as the ‘Humpback Comeback’. Between May and October 2016, humpback whales were seen in BC’s coastal waters in numbers that hadn’t been recorded in decades! Not only are humpbacks flooding into the area, they’re staying longer. Typically, humpback whales are seen in the spring as individuals pass us by on their way to their northern feeding grounds, where they spend the summer feeding on krill in Alaska. Then, we see them again in the fall as they pass through on their return trip to their winter breeding grounds in Hawaii or Mexico.
A map of the routes migratory humpbacks take as they travel from their breeding grounds in warm water to their feeding grounds in cold water. In the last few years, more humpbacks have been staying in southern British Columbia to feed instead of going all the way to Alaska. Graphic from the Hawaii Wildlife Fund website.
Only a few individuals typically stay here all summer and take advantage of the small fish and other tasty edibles that southern BC has to offer. But this past year, we had individuals hanging around for months, and many stayed long into the fall; in fact, if the food is good enough, some humpbacks may not even head south to breed at all! Female humpbacks don’t breed every year, so why go all the way to the tropics, where there is no food, if they can stay here and continue to eat well all winter? You may have experienced this survival instinct in another way. Who hasn’t cancelled a date in favour of ordering in pizza and watching a movie in pyjamas?
The result is that the humpbacks are moving back in. Not only are we seeing more of them in the usual places, we’re seeing them moving back into areas they haven’t occupied since pre-whaling times. This trend is continuing along the southern and central British Columbia coastlines, much to the delight of whale watchers, whale researchers and coastal residents. This comeback is a great sign for the whales’ population, as it means that their numbers are recovering from being overhunted during the early 1900’s. But there’s a catch: while the humpbacks were gone, their old stomping grounds have changed. Humans are using the ocean for things that they weren’t before. An increase in shipping and other boat traffic has made the waters crowded and noisy, and an increase in fishing activity has created an underwater obstacle course of fishing lines, crab and shrimp pots, and nets. A growing marine industry on the central coast is fish farming, where juvenile salmon are kept in open net pens. While humpback whales aren’t interested in eating the salmon, they have started using the space the fish farms occupy to rest and travel between their own feeding areas. Because of their size and inability to echolocate, humpbacks find it hard to see nets and fishing gear, and can blunder into them, getting tangled and stuck. This can cause injury and, in severe entanglements, drowning and death.
A map of the BC coast showing areas with both high humpback whale presence and high fishing activity. As humpback numbers increase, the likelihood of entanglements in fishing gear will increase as well. Graphic created by the BC Cetacean Sightings Network using data from Fisheries and Oceans Canada.
In 2016, twenty-two whale entanglements were reported by Fisheries and Oceans Canada. Of those, only six whales were successfully disentangled and saved. This is almost double the average number of whale entanglements per year, and researchers and rescuers are expressing concern. It is also likely that many more whales were entangled, but never reported, either because they were not spotted in time or because fishermen or fish farmers feared backlash if they reported whales caught in their gear. Nobody wants to be responsible for the death of such a large, intelligent and treasured animal, but officials urge anybody who sees a whale in trouble to report it to the marine mammal stranding hotline. Paul Cottrell, the coordinator of the stranding response team, has stressed that the sooner his team hears about an entangled whale, the better chance they have of successfully saving it.
The raw, damaged fluke of a juvenile humpback that was saved from drowning in a fish farm net after gruelling hours of work by the disentanglement team in September 2016. Photo by CBC News.
In the fall of 2016, three humpbacks were reported tangled in fish farm equipment within three months, two of which were in the same farm. One whale was saved, but two others drowned. Fish farm entanglements are generally very rare, and an investigation has been launched by Fisheries and Oceans to better understand this recent rash of entanglements. Whales getting caught in equipment is not just bad for the whales: fishermen and fish farmers don’t want to be known for hurting whales, and they don’t like replacing lost gear either. We hope for everyone’s sake that the fish farm investigation can come up with solutions that will help prevent further problems. The Department of Fisheries and Oceans as well as non-profit organizations like the Marine Education and Research Society are working tirelessly to monitor fisheries and educate fishermen in order to prevent negative interactions between fishermen and whales.
The Humpback Comeback is great news for the whales, but it means that we have to start learning to share our coastal waters with large, flippered neighbours once again. I have faith that we can find a way, and that the humpbacks will be here to stay.
Marine Wildlife Guide