Conservation is a strange mix of science and politics. What exactly the fraction of the mix is I would not hazard a guess, but probably the science of conservation biology is a small part of the total. That is not an excuse for anyone not to go into conservation as a career but you need to realize what you are walking into.
Many people have written about this but the latest radio announcements about wolf killing in western Canada got me thinking again about the problem of killing one native species to possibly protect another native species. Wolves eat caribou, mountain caribou are endangered, wolves are not (at the moment) endangered, therefore a simple solution: shoot A to save B. But think about this a bit and first of all realize that this is certainly not a scientific decision. Science tests hypotheses but it does not decree policies of action. The scientific issue buried in this controversy is whether or not shooting wolves will save the mountain caribou. How far, as a conservation scientist, do you trace the causality of a problem like this? Wolves eat a lot of moose as well as caribou. Oil and gas companies make roads to their wells and gas fields, paving the way for easy wolf dispersal to catch more moose or caribou. Moose love successional landscapes, and forestry companies love to make moonscapes by logging, generating successional landscapes. Deer also love farmland and successional landscapes, and mountain lions increase when deer increase. Mountain lions also take the occasional jogger. Where do we stop the causal chain?
If causality stops at the farm gate, wolves eat caribou therefore shoot them, life is simple. But to an ecologist this is missing the elephant in the room, our human use of landscapes. We make landscapes better for some species and worse for others, but we typically refuse to bear any responsibility for these landscape changes. How many logging companies or oil companies have been prosecuted for making wolves more abundant? So we go back to the farm gate and argue that killing wolves will have no effect on dwindling caribou because there are other predators out there – bears for example – that also eat caribou. And an honoured law of conservation biology is that once you get to a low population for the most part you are doomed no matter what happens. You cannot in a limiting case save a caribou herd of n = 1. But let us be optimistic as ecologists and argue that killing wolves will save the caribou. We have to add “this year” to that statement because, as Bob Hayes (2010) so elegantly argued in his book, once you start killing wolves you can never stop if that is your management solution. Caribou are caught in a nexus of wolves, bears, moose, deer, and elk in parts of western North America, and there is as yet no clear way of analyzing this nexus in a predictive manner. Killing wolves is the answer, but what is the question?
Money for management is yet another matter that enters the picture. Dollars spent on helicopter gunships cannot be spent on habitat improvements for other less charismatic species. So one needs value judgements here also, and this is not a scientific question but a policy one.
I think these conservation dilemmas are a general problem, and no doubt much is written about them. Do we kill an introduced species to save a native one? Do we forget about an introduced pest because a threatened bird species feeds on the pest? Do we get rid of an introduced weed that is poisonous to cattle but provides nectar for bees? Or in the present case do we kill one native species to potentially save another native species? Few of these questions are scientific questions and few can ever be sorted out by getting more data. So this is the problem I am not sure how to face. We go into conservation ecology to do science, but in the end we become a policy advisor that can be easily dismissed for political, social, or budget reasons. There is no way around this as far as I can see. If you think wolves are a valuable part of biodiversity, agitate not to kill them. If you think caribou will be preserved by killing wolves, go for the guns. All the arguments about the role of top predators in ecosystems (Ordiz et al. 2013, Ripple et al. 2014) can fall on deaf ears if society has a different value system than conservation biologists have.
Hayes, B. (2010) Wolves of the Yukon. Wolves of the Yukon Publishing, Smithers, B.C.
Ordiz, A., Bischof, R. & Swenson, J.E. (2013) Saving large carnivores, but losing the apex predator? Biological Conservation, 168, 128-133. doi: 10.1016/j.biocon.2013.09.024
Ripple, W.J., Estes, J.A., Beschta, R.L., Wilmers, C.C., Ritchie, E.G., Hebblewhite, M., Berger, J., Elmhagen, B., Letnic, M., Nelson, M.P., Schmitz, O.J., Smith, D.W., Wallach, A.D. & Wirsing, A.J. (2014) Status and ecological effects of the world’s largest carnivores. Science, 343, 1241484. doi: 10.1126/science.1241484