Many species around the world are declining. This is true even in my own field of marine mammal science, where the species are incredibly charismatic and great for garnishing attention from the public. Most notably, the Chinese river dolphin, the baiji, was declared extinct in 2006. However, several other species and populations are on the verge of following suit. These including the vaquita, the Maui’s dolphin, and the North Atlantic right whale. The interesting thing these examples have in common is that we know why each is declining. However, the human activities threatening these critically endangered species are being allowed to continue.
Oh, there are plenty of efforts to reduce the impacts. However, the vast majority of conservation actions seek only to minimise the impact of increasing human activity on species of interest. For instance, new fishing gear does reduce bycatch and the re-routing of shipping lanes and the slowing of ships does reduce collisions. Better still we can bring out the holy grail of marine conservation, the marine protected area (MPA), to limit one or more human activities in a given area.
There is indeed evidence that MPAs can help reduce declines of marine mammal species in the face of human activities. However, their success depends upon the appropriate application of a reasonable amount of data, as well as a large size, old age, isolation and comprehensive enforcement. In any case, MPAs rarely reduce any restricted human activities across their wider region, merely displacing it instead. For example, on occasions when fishing activity is restricted, fishermen have come to realise that catches near the MPA do indeed go up. This has given rise to a practice known as “fishing the line” where the density of fishing along the MPA boundaries increases to unprecedented levels. For marine mammals, this often means an almost continuous line of nets around their prime habitat. Woe betides those who wander out of the protected regions.
The other problem is the sheer range of human pressures. Let us consider, for example, the humble harbour porpoise, where many populations are exposed to fishing activity, pile driving, seismic surveys for oil and gas, drilling noise, military and fishing sonar, bridge noise, contaminants, oil spills (both accidental and operational), marine debris (including discarded fishing gear and consumable plastic bags) and climatic change. While many countries have extensive environmental impact assessment laws, assessments of cumulative impact resulting from this onslaught are typically very limited. This is because there are almost certainly many unknown or under-appreciated emergent impacts arising from the various combinations of exposures. As a consequence, cumulative impact management is almost non-existent. Migratory species are even more at risk, as consideration of activities beyond the immediate jurisdiction is even more difficult and, therefore, even more rare.
The upshot of all of this is that the majority of conservation actions, while commendable, are not going to save a species, which instead face an inevitable loss in what is effectively a war of attrition. The reason for this is simply that the conservation measures merely place a small bandage on an all-too-often gaping wound. To illustrate this, we shall return to the example of the new fishing gear.
Bycatch may indeed be lowered, but any reduction in prey availability or exclusion of animals from their food source arising from the fishery remains, as does operational noise, the introduction of machine oils, other chemicals and various objects that can be washed into the ocean. Lost fishing gear can still become an entanglement risk for cetaceans. Furthermore, any future increase in the size of the fishing fleet may nullify any benefit of the new gear.
Fortunately, there is another way. Instead of focusing on specific issues, it is possible to approach the problems more holistically by addressing the source. In this way, we can simultaneously contend with bycatch, overfishing, and a considerable amount of marine debris by simply looking to reduce the amount of fish we remove from the oceans. Likewise, noise from oil and gas surveys and drilling operations, oil spills, micro-plastics, ocean acidification and even climate change can all be tackled through a concerted effort to reduce our oil usage.
But how realistic is this? While eliminating oil or fish consumption completely is unlikely, we can actually do quite a lot to reduce the unnecessary extraction of both with relatively little effort. Consider that the International Energy Agency has determined that over half of the CO2 savings needed to cut global CO2 production by 50 % can be achieved through end-use fuel switching and end-use fuel and electricity efficiency alone. Similarly, the Food and Agriculture Organization of the United Nations has calculated that roughly one-third of all food produced for human consumption in the world is lost or wasted, and this figure doesn’t even consider non-target fish discarded as bycatch.
Obviously, eliminating this wastage would not be directly translated into directly comparable on-the-water improvements, but how much better would the oceans be if there were even 20 % fewer fishing boats, or 15 % fewer oil tankers and seismic surveys?
Addressing the problem is also reasonably straight forward. Both fishing and fossil fuels are heavily subsidised industries, making wastage affordable. Eliminating these subsidies would push up prices and make such waste uneconomical. Some of these subsidies could also be redirected to fund research into, for example, true alternatives to our power needs in search of real longer-term solutions.
Attacking the source of the problem also allows conservation biologists to act proactively, rather than reacting simply to the next proposed industrial development. One important side-effect would be the emergence of clear, consistent messaging from previously unconnected groups, such as those working to protect narwhals from seismic noise and those trying to reduce ingestion of plastic debris in porpoises. We, as marine mammal biologists, would also be adding our voices to those already working to address climate change or halt over-fishing, increasing the weight of science in support of reductions in fossil fuel and fish consumption.
We can continue to spend considerable effort to limit the increase in the total impact of human activity on marine mammals. However, we must refocus at least some attention towards reductions in human need for marine resources. If we cannot achieve this, there will be some species that we simply will never be able to save.
Andrew J. Wright
George Mason University,
Department of Environmental Science and Policy,
Fairfax, Virginia, USA
This article is dedicated to the memory of Rev. Fred Wright (7th July 1915 – 23rd March 2014)