How we all kill whales
By Michael Moore
My first job after veterinary school in 1983 was for the International Whaling Commission examining the efficacy of explosive harpoons for killing fin whales on an Icelandic whaling vessel. Later, I encountered a very different way of killing whales. A North Atlantic right whale was first sighted entangled in fishing gear in May of 1999. Five months later it was dead off Cape May, New Jersey. The entangling rope and gillnet, bound around both armpits, and tightly stretched over its back, had dissected off the blubber leaving a massive wound (below) while it was still alive.
These two very contrasting scenarios of how humans kill whales have preoccupied me ever since. The whalers were intent on killing for profit, and did so with remarkable efficiency. My concerns centred on whether the hunt was sustainable. In contrast, the entangled animal was killed without intent, but I was extremely concerned about the animal’s welfare while it was taking five months to die. Some anti-whaling advocates criticise commercial whaling, while ignoring the unintentional killing of whales in many countries. The idea that individuals should judge another nation’s motivations and methods of killing whales, struck and strikes me as being far from clear ethically.
There are a number of conservation and welfare factors at work in these two ways that man kills whales today, whether by intent or not. Here I focus primarily on commercial whaling and entanglement, but there are other topics that could be included, such as scientific and aboriginal whaling, euthanasia of living stranded whales, lethal and sublethal vessel strikes, effects of ocean noise and contaminants on whales, and premature death of larger odontocetes in captive display. ‘Whaling’ is defined in the Oxford English Dictionary as “the action, practice, or business of catching whales”. Whenever fixed fishing gear is set in areas that are known to be frequented by large whales, there is a probability (that is gear and species dependent) that whales will be captured by the gear and that these encounters will affect the whale’s welfare and sometimes be lethal. Many of these animals if large enough to break out are subsequently ‘released’ as they swim off with the entangling gear, however, as with other catch and release fisheries and commercial fishery bycatch release, animals often die. Likewise, some whales species are caught on the bulbous bows of large ships and brought to port dead.
Whaling by Design
Killing whales with harpoons and associated tools has been commercially profitable for at least 1000 years, since King Sancho (the Wise) of Navarre levied a tax on baleen plates in 1150. Open boat whaling evolved from shore based whaling to European and American whaling from larger mother vessels offshore. These fisheries relied primarily on handheld harpoons, using drag to tire a whale to enable delivery of lances to vital organs in the chest. The explosive harpoon and faster vessels later enabled wholesale, sequential devastation of balaenopterid and sperm whale stocks around the world. Most of the concern at that time was with loss of stocks, many of which have yet to recover significantly. It was only in recent decades that the nature of the death caused by an explosive harpoon became a central theme of some anti-whaling protests. The message was mixed: hunting whales is cruel; there are not enough of them. Explosive harpoons can be comparable to other hunting methods. The bigger issues are: sufficiency of animals to sustain a given mortality, not knowing population sizes at all well; and our ongoing abject failure to manage whale stocks, indeed any high seas fishery, sustainably. We should not be killing whales by design.
Whaling by default
Humans also kill whales unintentionally: vessel strike, fishery bycatch, marine debris, food chain effects, and oil and chemical spills. Pinniped and cetacean mortalities from acute fishing gear bycatch entanglement have been estimated to be hundreds of thousands of individuals per year. Large whales are often powerful enough to break free from the anchored fishing gear and swim off, with residual gear around their appendages. This gear adds substantial drag, depleting energy reserves, and ultimately the animal dies. Such mortalities are certainly underestimated, as some large whale species are negatively buoyant and sink on death especially if they are lipid depleted. On the eastern North American Continental shelf death by entanglement in fishing gear is on aggregate the most common diagnosed cause of death among 323 individuals from eight large whale species: 18% entangled, 10% vessel struck, 14% non-human related, and 57% undiagnosed in a sample of 323 animals. In contrast to commercial and aboriginal whaling, and vessel strike, the time to death for whales that do not drown acutely can be extremely prolonged. Fatally entangled right whales can take an average of six months to die. Entanglement scars also give evidence of persistent sub-lethal fishing gear interactions in North Atlantic right whales. For the period 1980-2009 in a sample of 626 whales, 83% had been entangled at least once, 59% more than once, with 26% acquiring new scars every year, with no obvious trend in terms of incidence. Another way to think about this is that the majority of North Atlantic right whales are repeatedly more restrained than any animal in a zoo. We tend to talk about the ocean as wilderness yet, in this area and others, it is far from that, being the workplace of industries that kill whales by design and default.
Palliative measures have included removal of entangling fishing gear by trained disentanglement teams (IWC, 2010), with recent international training. However prevention of entanglement is the only lasting solution, given the difficulty of disentanglement. Prevention measures have largely hinged on gear modification, such as sinking ground lines and breakaway links. There needs to be a fundamental shift in terms of fishery management for mitigating whale entanglement not only using tested, practical, safe and effective gear modification, but also by focusing on keeping the gear and the whales separate in time and space. Such a proposal may seem radical and unacceptable from a fishing industry perspective, however it would create Marine Protected Areas that could serve fishery as well as marine mammal conservation agendas.
Michael Moore has a veterinary degree from the University of Cambridge, and a PhD from the Woods Hole Oceanographic Institution (WHOI)/ Massachusetts Institute of Technology Joint Program in Biological Oceanography. He is the Director of the WHOI Marine Mammal Center and provides veterinary support for management of marine mammal strandings on Cape Cod, MA, USA by the International Fund for Animal Welfare. He is the author of the paper ‘How we all kill whales‘, published in ICES Journal of Marine Science.
The ICES Journal of Marine Science publishes articles, short communications, and critical reviews that contribute to our scientific understanding of marine systems and the impact of human activities. The Journal serves as a foundation for scientific advice across the broad spectrum of management and conservation issues related to the marine environment.