Tag Archives: biodiversity

On Wildlife Management

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There are two global views about wildlife management that are echoed in conservation biology. The first view is that we manage wildlife for the sake of wildlife so that future generations have the ability to see what we see when we go out into the woods and fields. The second view is that we manage wildlife and indeed all of nature for humans to exploit. The second view was elegantly summarized many years ago by White (1967):

“Our science and technology have grown out of Christian attitudes toward man’s relation to nature which are almost universally held not only by Christians and neo-Christians but also by those who fondly regard themselves as post-Christians. Despite Copernicus, all the cosmos rotates around our little globe. Despite Darwin, we are not, in our hearts, part of the natural process. We are superior to nature, contemptuous of it, willing to use it for our slightest whim. The newly elected Governor of California, like myself a churchman but less troubled than I, spoke for the Christian tradition when he said (as is alleged), “when you’ve seen one redwood tree, you’ve seen them all.” (p.1206)

The first view of wildlife is now for ecologists the dominant conservation ethic of our time, the recognition that wildlife and nature in general has intrinsic value (Vucetich et al. 2015). Yet when there are conflicts in environmental management, the second view that humans trump all comes to the fore. Think of examples in your region. When caribou and moose are declining, the shout goes up to shoot the wolves. The golden example of this is perhaps Norway where wolves are nearly all gone and moose are superabundant and fed in winter so that there are plenty for hunters to shoot in the following year. Where domestic and feral cats threaten bird populations, the view typically expressed is that cats are our pets and quite cute, and certainly cannot be regulated or controlled as feral pests.

One of the main defenses of biodiversity conservation during the last 20 years has been the role of ecosystem services. The utilitarian view that ecosystems do things for humans that you can then calculate in dollars has been used to carry conservation forward for those who subscribe to the second global view of nature as something that exists only for our exploitation. Two recent reviews are critical of this approach. Silvertown (2015) argues that the ecosystem services paradigm has been oversold and suggests alternatives. An important critical overview of the conundrum of biodiversity research is presented very clearly in Vellend (2017) and is essential reading for all those interested in environmental management issues and the collision of science and human values expressed in our two global views of biodiversity conservation.

Wildlife managers must operate with the first view in mind to manage wildlife for wildlife but at the same time must act in ways determined by their political masters to adopt the second view of human values over wildlife. Ecologists walk a thin line in this dilemma. A good example is the book by Woinarski et al. (2007) which details the disastrous state of environmental management in northern Australia. There are courageous attempts to resolve these management problems and to bridge the two global views by bringing ecological knowledge into policy development and environmental management (e.g. Morton et al. 2009, Lindenmayer et al. 2015). Many others beginning with Aldo Leopold in North America and many others in Europe have made elegant pleas for the first global view of wildlife conservation. The attempts now to bridge this gap between exploitation and preservation are to bring social sciences into environmental research programs, and these efforts can be increasingly effective. But there is a large contingent of the public that support the second view that humans are the most important species on earth. The increasing collision of rising human populations, resource shortages, and climate change produce a perfect storm of events that place wildlife management and environmental sustainability in a difficult position. Everyone who is able must speak up for the first global view in order to achieve a sustainable society on earth and for wildlife and biodiversity in general to be protected for future generations.

Lindenmayer, D.B.,et al. 2015. Contemplating the future: Acting now on long-term monitoring to answer 2050’s questions. Austral Ecology 40(3): 213-224. doi: 10.1111/aec.12207.

Morton, S.R., et al. 2009. The big ecological questions inhibiting effective environmental management in Australia. Austral Ecology 34(1): 1-9. doi: 10.1111/j.1442-9993.2008.01938.x.

Silvertown, J. 2015. Have Ecosystem Services been oversold? Trends in Ecology & Evolution 30(11): 641-648. doi: 10.1016/j.tree.2015.08.007.

Vellend, M. 2017. The biodiversity conservation paradox. American Scientist 105(2): 94-101.

Vucetich, J.A., Bruskotter, J.T., and Nelson, M.P. 2015. Evaluating whether nature’s intrinsic value is an axiom of or anathema to conservation. Conservation Biology 29(2): 321-332. doi: 10.1111/cobi.12464.

White, L., Jr. 1967. The historical roots of our ecologic crisis. Science 155(3767): 1203-1207.

Woinarski, J., Mackey, B., Nix, H., and Traill, B. 2007. The Nature of Northern Australia: Natural values, ecological processes and future prospects. Australian National University E Press, Canberra. (available at: http://press.anu.edu.au/publications/nature-northern-australia)

On Biodiversity and Ecosystem Function

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I begin with a quote from Seddon et al. (2016):

“By 2012, the consensus view based on 20 years of research was that (i) experimental reduction in species richness, at any trophic level, negatively impacts both the magnitude and stability of ecosystem functioning [12,52], and (ii) the impact of biodiversity loss on ecosystem functioning is comparable in magnitude to other major drivers of global change [13,54].”

The references are to Cardinale et al. (2012), Naeem et al. (2012), Hooper et al. (2012), and Tilman et al. (2012).

The basic conclusion of the literature cited here is that with very extensive biodiversity loss, ecosystem function such as primary productivity will be reduced. I first of all wonder which set of ecologists would doubt this. Secondly, I would like to see these papers analysed for problems of data analysis and interpretation. A good project for a graduate class in experimental design and analysis. Many of the studies I suspect are so artificial in design as to be useless for telling us what will really happen as natural biodiversity is lost. At best perhaps we can view them as political ecology to try to convince politicians and the public to do something about the true drivers of the mess, climate change and overpopulation.

Too many of the graphs I see in published papers on biodiversity and ecosystem function look like this (from Maestre et al. (2012): data from 224 global dryland plots)

There is a trend in these data but zero predictability. And even if you feel that showing trends are good enough in ecology, the trend is very weak.

Many of these analyses utilize meta-analysis. I am a critic of the philosophy of meta-analysis and not alone in wondering how useful many of these are in guiding ecological research (Vetter et al. 2013, Koricheva, and Gurevitch 2014). Perhaps the strongest division in deciding the utility of these meta-analyses is whether one is interested in general trends across ecosystems or predictability which depends largely on understanding the mechanisms behind particular trends.

Another interesting aspect of many of these analyses lies in the preoccupation with stability as a critical ecosystem function maintained by species richness. In contrast to this belief, Jacquet et al. (2016) have argued that in empirical food webs there is no simple relationship between species richness and stability, contrary to conventional theory.

Finally, another quotation from Naeem et al. (2012) which raises a critical issue on which ecologists need to focus more:

“In much of experimental ecological research, nature is seen as the complex, species-rich reference against which treatment effects are measured. In contrast, biodiversity and ecosystem functioning experiments often simply compare replicate ecosystems that differ in biodiversity, without any replicate serving as a reference to nature. Consequently, it has often been difficult to evaluate the external validity of biodiversity and ecosystem functioning research, or how its findings map onto the “real” worlds of conservation and decision making. Put another way, what light can be shed on the stewardship of nature by microbial microcosms that have no analogs in nature, or by experimental grassland studies in which some plots have, by design, no grass species? “ (page 1403)

And for those of you who are animal ecologists, the vast bulk of these studies were done on plants with none of the vertebrate browsers and grazers present. Perhaps some problems here.

Whatever one’s view of these research paradigms, no questions will be answered if we lose too much biodiversity.

Cardinale, B.J., Duffy, J.E., Gonzalez, A., Hooper, D.U., Perrings, C., Venail, P., Narwani, A., Mace, G.M., Tilman, D., Wardle, D.A., Kinzig, A.P., Daily, G.C., Loreau, M., Grace, J.B., Larigauderie, A., Srivastava, D.S. & Naeem, S. (2012) Biodiversity loss and its impact on humanity. Nature, 486, 59-67. doi: 10.1038/nature11148

Hooper, D.U., Adair, E.C., Cardinale, B.J., Byrnes, J.E.K., Hungate, B.A., Matulich, K.L., Gonzalez, A., Duffy, J.E., Gamfeldt, L. & O/’Connor, M.I. (2012) A global synthesis reveals biodiversity loss as a major driver of ecosystem change. Nature, 486, 105-108. doi: 10.1038/nature11118

Jacquet, C., Moritz, C., Morissette, L., Legagneux, P., Massol, F., Archambault, P. & Gravel, D. (2016) No complexity–stability relationship in empirical ecosystems. Nature Communications, 7, 12573. doi: 10.1038/ncomms12573

Koricheva, J. & Gurevitch, J. (2014) Uses and misuses of meta-analysis in plant ecology. Journal of Ecology, 102, 828-844. doi: 10.1111/1365-2745.12224

Maestre, F.T. et al. (2012) Plant species richness and ecosystem multifunctionality in global drylands. Science, 335, 214-218. doi: 10.1126/science.1215442

Naeem, S., Duffy, J.E. & Zavaleta, E. (2012) The functions of biological diversity in an Age of Extinction. Science, 336, 1401.

Seddon, N., Mace, G.M., Naeem, S., Tobias, J.A., Pigot, A.L., Cavanagh, R., Mouillot, D., Vause, J. & Walpole, M. (2016) Biodiversity in the Anthropocene: prospects and policy. Proceedings of the Royal Society B: Biological Sciences, 283, 20162094. doi: 10.1098/rspb.2016.2094

Tilman, D., Reich, P.B. & Isbell, F. (2012) Biodiversity impacts ecosystem productivity as much as resources, disturbance, or herbivory. Proceedings of the National Academy of Sciences 109, 10394-10397. doi: 10.1073/pnas.1208240109

Vetter, D., Rücker, G. & Storch, I. (2013) Meta-analysis: A need for well-defined usage in ecology and conservation biology. Ecosphere, 4, art74. doi: 10.1890/ES13-00062.1

On Conservation

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The question of how ecology can guide decisions about conservation actions is a vexed one of which much has already been written with respect to conservation triage (Bottrill et al. 2009, Gerber 2016). The global question – what should we do now? – produces two extreme answers: (1) do nothing. The biodiversity on earth has gone through many climatic fluctuations imposed by geology and planetary physics and these forces are out of our hands. Or (2) we must protect all species because we do not know if they are important for ecosystem function. The government recognizes that (2) is impossible, and either reflects back to answer (1) or politely asks scientists to suggest what is possible to achieve with limited funding. John Wiens (2016) in an interesting discussion in the British Ecological Society Bulletin (December 2016, pp 38-39) suggests that two possible solutions to this conundrum are to get more funding for conservation to reduce this clear financial limitation, or secondly to move from the conservation of individual species to that of ecosystems. The problem he and many others recognize is that the public at large fall in love with individual species much more readily than with ecosystems. It is the same problem medical science often faces with contributions from wealthy people – attack individual diseases with my funding, not public health in general.

Ecologists face this dilemma with respect to their research agenda and research grants in general – what exactly can you achieve in 3-5 years with a small amount of money? If your research is species-specific, something useful can often be studied particularly if the threatening processes are partly understood and you adopt an experimental approach. If your research is ecosystem oriented and your funds are limited you must generally go to the computer and satellite ecology to make any short term research possible. This problem of larger scale = larger costs can be alleviated if you work in a group of scientists all addressing the same ecosystem issue. This still requires large scale funding which is not as easily obtained as ecologists might like. The government by contrast wishes more and more to see results even after only a few years, and asks whether you have answered your original question. The result is a patchwork of ecological data which too often makes no one happy.

If you want a concrete example, consider the woodland caribou of western Canada (Schneider et al. 2010). For these caribou Hebblewhite (2017) has clearly outlined a case in which the outcomes of any particular action are difficult to predict with the certainty that governments and business would be happy with. Many small herds are decreasing in size, and one path is to triage them, leaving many small herds to go extinct and trying to focus financial resources to save larger herds in larger blocks of habitat for future generations. The problem is the oil and gas industry in western Canada, and hence the battle between resources that are worth billions of dollars and a few caribou. Wolf control can serve as a short term solution, but it is expensive and temporary. Governments like action even if it is of no use in the long term; it makes good media coverage. None of these kinds of conservation decisions are scientific in nature, and must be policy decisions by governments. It flips us back into the continuum between options (1) and (2) in the opening paragraph above. And for governments policy decisions are more about jobs and money than about conservation.

The list of threatened and endangered species that make our newspapers are a tiny fraction of the diversity of species in any ecosystem. There is no question but that many of these charismatic species are declining in numbers, but the two larger questions are: will this particular species go extinct? And if this happens will this make any difference to ecosystem function? There is scarcely a single species of all that are listed as threatened and endangered for which ecologists have a good answer to either of these questions. So the fallback position to option (1) is that we have a moral obligation to protect all species. But this fallback position leads us even further out of science.

In the end we must ask as scientists what we can do with the understanding we have, and what more needs to be done to improve this understanding. Behind all this scientific research looms the elephant of climate change which we either ignore or build untestable computer models to make ‘predictions’ which may or may not occur, if only because of the time scales involved.

None of these problems prevents us from taking actions on conservation on the ground (Wiens 2016a). We know that, if we take away all the habitat, species abundances will decline and some will go extinct. Protecting habitat is the best course of action now because it needs little research to guide action. There is much to know yet about the scale of habitats that need preservation, and about how the present scale of climate change is affecting protected areas now. Short term research can be most useful for these issues. Long-term research needs to follow.

Bottrill, M.C., et al. (2009) Finite conservation funds mean triage is unavoidable. Trends in Ecology & Evolution, 24, 183-184. doi: 10.1016/j.tree.2008.11.007

Gerber, L.R. (2016) Conservation triage or injurious neglect in endangered species recovery. Proceedings of the National Academy of Sciences USA, 113, 3563-3566. doi: 10.1073/pnas.1525085113

Hebblewhite, M. (2017) Billion dollar boreal woodland caribou and the biodiversity impacts of the global oil and gas industry. Biological Conservation, 206, 102-111. doi: 10.1016/j.biocon.2016.12.014

Schneider, R.R., Hauer, G., Adamowicz, W.L. & Boutin, S. (2010) Triage for conserving populations of threatened species: The case of woodland caribou in Alberta. Biological Conservation, 143, 1603-1611. doi: 10.1016/j.biocon.2010.04.002

Wiens, J.A. (2016) Is conservation a zero-sum game? British Ecological Society Bulletin 47(4): 38-39.

Wiens, J.A. (2016a) Ecological Challenges and Conservation Conundrums: Essays and Reflections for a Changing World. John Wiley and Sons, Hoboken, New Jersey. 344 pp. ISBN: 9781118895108

On Mushrooms, Monitoring, and Prediction

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Mushrooms probably run the world but we do not know this yet. My old friend Jim Trappe from Oregon State told me this long ago, and partly as a result of this interaction we began counting mushrooms at our boreal forest sites near Kluane, Yukon in 1993, long ago and even before the iPhone was invented. Being zoologists, we never perhaps appreciated mushrooms in the forest, but we began counting and measuring mushrooms appearing above ground on circular plots of 28m2. With the help of many students, we have counted about 12,000 plots over 24 years, even after being told by one Parks Canada staff member that they could not assist us because “real men do not count mushrooms”. At least we know our position in life.

At any rate the simple question we wanted to ask is whether we can predict mushroom crops one year ahead. We know that many species eat these mushrooms, from red squirrels (who dry mushrooms on spruce tree branches so they can be stored for later consumption), to moose (Alice Kenney has photographed them kneeling down to munch mushrooms), to caribou (Art Rodgers has videoed) to small rodents and insects, not to mention Yukon residents. We know from natural history observations that mushroom crops in the boreal forest are highly variable from year to year, ranging from 0.1 to 110 g/10m2 wet weight, for a CV of 138% (Krebs et al. 2008). The question is how best to predict what the crop will be next year.  Why do we want to know next year’s crop? Two reasons are that large crops provide food for many animals and thus affect overall ecosystem dynamics, and secondly that the essence of understanding in science is the ability to understand why changes occur and if possible to be able to predict them.

We assume it has to be driven by climate, so we can gather together climate data and it is here that the questions arise as to how to proceed. At one extreme we can gather annual temperatures and annual rainfall, and at the other extreme we can gather daily rainfall. We first make the assumption that it is only the weather during the summer from May to August that is relevant for our statistical model, so annual data are not useful. But then we are faced with a nearly infinite number of possible weather variables. We have chosen months as the relevant weather grouping and so we tally May temperature averages, May rainfall totals, growing degree days above 5°C, etc. for all the years involved. This leads us into a statistical nightmare of having far more independent variables than measurements of mushroom crops. If we have, for example, 15 possible measures of temperature and rainfall we can generate 32,768 models ignoring all the interactive models. There are several standard ways of dealing with this statistical dilemma, with stepwise regression being the old fashioned approach. But new methods and advice continue to appear (e.g. Elith et al. 2008, Ives 2015). The ability to compare different regression models with the AIC approach helps (Anderson 2008) as long as there is some biological basis to the models.

We adopted a natural history approach, given that many people believe that large mushroom crops are associated with above average rainfall. We are blessed in the Yukon with only one possible crop of mushrooms per year (at least for the present), so that also simplifies the kinds of models one might use. At any rate (as of 2016) the simplest regression model to predict mushroom biomass in a particular year turned out to involve only rainfall from May (early spring) of the previous year, with R2 = 0.55. But this success has just led us into more questions of why we cannot find a model that will explain the remaining 45% of the variance in annual crops. Should one just give up at this point and be happy that we can explain a large part of the annual variation, or should one press on doing more modelling and looking for other variables? Data dredging is more and more becoming an issue in the ecological literature, and in particular in ecological events likely to be at least partly associated with climate (Norman 2014).

Another ecological problem has been that we do not identify the species of mushrooms involved and deal only in biomass. It may be that species identification would help us to improve predictability. But there are perhaps 40 or more species of mushrooms in our part of the boreal forest, and so we now have to become mycologists. And then as Jim Trappe would tell me, all of this ignores the important questions of what is going on with these fungi underground, so we have only scratched the surface.

The next question is how long a predictive model based on weather will continue to hold in an area subject to rapid climate change. Climate change in the southern Yukon is relatively rapid but highly variable from year to year, and only continuing monitoring will keep us informed about how the physical measurements of temperature and rainfall translate into events in the biological world.

All of this is to say that counting and measuring mushrooms is enjoyable and keeps one connected to the real world. It is also a free type of good exercise, and part of citizen science. Continued monitoring is necessary to see how the boreal ecosystem responds to changing climate and to see if good years for mushroom crops become more frequent. And in good years, many kinds of mushrooms are good to eat if you can beat the squirrels to them.

Anderson, D.R. (2008) Model Based Inference in the Life Sciences: A Primer on Evidence. Springer, New York. ISBN: 978-0-387-74073-7

Elith, J., Leathwick, J.R. & Hastie, T. (2008) A working guide to boosted regression trees. Journal of Animal Ecology, 77, 802-813. doi: 10.1111/j.1365-2656.2008.01390.x

Ives, A.R. (2015) For testing the significance of regression coefficients, go ahead and log-transform count data. Methods in Ecology and Evolution, 6, 828-835. doi: 10.1111/2041-210X.12386

Krebs, C.J., Carrier, P., Boutin, S., Boonstra, R. & Hofer, E.J. (2008) Mushroom crops in relation to weather in the southwestern Yukon. Botany, 86, 1497-1502. doi: 10.1139/B08-094

Norman, G.G. (2014) Data dredging, salami-slicing, and other successful strategies to ensure rejection: twelve tips on how to not get your paper published. Advances in Health Sciences Education, 19, 1-5. doi: 10.1007/s10459-014-9494-8

Predator Free New Zealand

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The New Zealand Government announced in July 2016 the adoption of Predator Free New Zealand 2050, a program for the control and eradication of introduced pests. It is setting up a new public-private partnership company by the beginning of 2017 to help fund regional large-scale predator eradication programs with the anticipated funding ratio of 1 government dollar to 2 private dollars. This is a bold new program grounded in the fundamental research of an excellent array of conservation biologists that have carried out the field research underpinning what needs to be done to protect native biodiversity in New Zealand.

Because of its isolation and the complete absence of endemic terrestrial vertebrate predators, New Zealand has become a basket case for the conservation of native species after the introduction of four species of rodents – Norway rat, black rat, house mouse, and Pacific rat (kiore) – as well as the possum (introduced for fur), the stoat (to “control rodents”) and the hedgehog (Goldson et al. 2015). The initial focus in this program will be on rats, stoats, and possums. Rat control on islands has already been a major success story for New Zealand scientists (Russell et al. 2016).

Four short-term goals have been set for 2025 for the Predator Free New Zealand project:

  • An additional 1 million hectares of land where pests have been supressed or removed through Predator Free New Zealand partnerships
  • Development of a scientific breakthrough capable of removing at least one small mammal predator from New Zealand entirely
  • Demonstration areas of more than 20,000 hectares that are predator free without the use of fences
  • Complete removal of all introduced predators from offshore island nature reserves

This is a striking vision, and it puts New Zealand at the forefront of global conservation efforts and goals. Everyone appreciates that it will not be easy. In particular there has to be careful attention to the order in which pests are removed. Competition between invasive species as well as predation among them often has counterintuitive results. In New Zealand when rats were removed from experimental plots, house mice increased, and when possums were removed rats increased (Ruscoe et al. 2011). When stoats (Mustela erminea) were removed, there was no effect on rat or mouse abundance, contrary to what a model predicted (Tompkins and Veltman 2006). At the moment there is no clear way to do a total removal of these pest mammals all at once rather than sequentially.

One of the major stimuli for this program has been stopping bovine TB transmission from possums to cattle. The brushtail possum (introduced from Australia) is a disease reservoir and vector of bovine tuberculosis to cattle. Extensive control programs for possums are applied over about 10 million ha in New Zealand by the spreading of 1080 poison baits and trapping, and this program has reduced possum populations to low numbers but not eliminated this pest (Byrom et al. 2016). Poisoning for possum control also reduces stoats and rats, and so has secondary benefits for native biodiversity. A total of approximately NZ$55 million is spent each year on this control program, and if possums could be eradicated, the financial benefits would be great for the cattle industry. Byrom et al. (2016) showed that possum reduction by poisoning had benefits not only for TB transmission but also for increases in vegetation (reduced herbivory), invertebrate, frog and bird abundance.

Two worries are that the social license to continue widespread use of deadly poisons will erode in the future and secondly that the pest species will eventually evolve resistance to the poisons. For these reasons much research is needed on more clever ways of achieving pest reduction and elimination.

The success of island eradications in the past 20 years has emboldened ecologists to wish for successes on larger and larger scales. But eradication is a complex problem and there is a long history of success and failures, particularly in insect populations (Myers et al. 2000). But by reaching out with a direct challenge to applied ecologists, molecular biologists, chemists, and other clever scientists, New Zealand has moved the standard forward in ways that bode well for understanding more why ecology matters.

And then it is on to the feral cats.

Byrom, A.E., Innes, J. & Binny, R.N. (2016) A review of biodiversity outcomes from possum-focused pest control in New Zealand. Wildlife Research, 43, 228-253. doi: 10.1071/WR15132

Campbell, K.J., et al. (2015) The next generation of rodent eradications: Innovative technologies and tools to improve species specificity and increase their feasibility on islands. Biological Conservation, 185, 47-58. doi: 10.1016/j.biocon.2014.10.016

Goldson, S.L., et al. (2015) New Zealand pest management: current and future challenges. Journal of the Royal Society of New Zealand, 45, 31-58. doi: 10.1080/03036758.2014.1000343

Myers, J.H., Simberloff, D., Kuris, A.M. & Carey, J.R. (2000) Eradication revisited: dealing with exotic species. Trends in Ecology and Evolution, 15, 316-320.

Ruscoe, W.A. et al. (2011) Unexpected consequences of control: competitive vs. predator release in a four-species assemblage of invasive mammals. Ecology Letters, 14, 1035-1042. doi: 10.1111/j.1461-0248.2011.01673.x

Russell, J.C. & Broome, K.G. (2016) Fifty years of rodent eradications in New Zealand: another decade of advances. New Zealand Journal of Ecology, 40, 197-204. doi: 10.20417/nzjecol.40.22.

Tompkins, D.M. & Veltman, C.J. (2006) Unexpected consequences of vertebrate pest control: predictions from a four-species community model. Ecological Applications, 16, 1050-1061. doi: 10.1890/1051-0761(2006)016[1050:UCOVPC]2.0.CO;2

 

Biodiversity Conundrums

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Conservation ecologists face a conundrum, as many have pointed out before. As scientists we do not make policy. Most conservation problems are essentially a moral issue of dealing with conflicts in goals and allowable actions. Both the United States and Canada have endangered species legislation in which action plans are written for species of concern. In the USA species of concern are allotted some funding and more legal protection than in Canada, where much good material is written but funding for action or research is typically absent. What is interesting from an ecological perspective is the list of species that are designated as endangered or threatened. Most of them can be described colloquially as the “charismatic megafauna”, species that are either large or beautiful or both. There are exceptions of course for some amphibians and rare plants, but by and large the list of species of concern is a completely non-random collection of organisms that people see in their environment. Birds and butterflies and large mammals are at the head of the list.

All of this is fine and useful because it is largely political ecology, but it raises the question of what will happen should these rescue plans for threatened or endangered species fail. This question lands ecologists in a rather murky area of ecosystem function, which leads to the key question: how is ecosystem function affected by the loss of species X? The answer to this question depends very much on how you define ecosystem function. If species X is a plant and the ecosystem function measured is the uptake of CO2 by the plant community, the answer could be a loss of function, no change, or indeed an increase in CO2 uptake if species X for example is replaced by a weed that is more productive that species X. The answer to this simple question is thus very complicated and requires much research. For a hypothetical example, plant X may be replaced by a weed that fixes more CO2, and thus ecosystem function is improved as measured by carbon uptake from the atmosphere. But the weed may deplete soil nitrogen which could adversely affect other plants and soil quality. Again more data are needed to decide this. If the effect size is small, much research could provide an ambiguous answer to the original question, since all measurement involves errors.

So now we are in a box, a biodiversity conundrum. The simplest escape is to say that all species loss is undesirable in any ecosystem, a pontification that is more political than scientific. And, for a contrary view, if the species lost is a disease organism, or an insect that spreads human diseases, we will not mourn its passing. In practice we seem to agree with the public that the species under concern are not all of equal value for conservation. The most serious outcome of this consideration is that where the money goes for conservation is highly idiosyncratic. There are two major calls for funding that perhaps should not be questioned: first, for land (and water) acquisition and protection, and second, for providing compensation for the people whose livelihoods are affected by protected areas with jobs and skills that improve their lives. The remaining funds need to be used for scientific research that will further the cause of conservation in the broad sense. The most useful principle at this stage is that all research has a clear objective and a clear list of what outcomes can be used to judge its success. For conservation outcomes this judgement should be clear cut. Currently they are not.

When Caughley (1994) described the declining population paradigm and the small population paradigm he clearly felt that the small population paradigm, while theoretically interesting, had little to contribute to most of the real world problems of biodiversity conservation. He could not have imagined at the time how genetics would develop into a powerful set of methods of analysis of genomes. But with a few exceptions the small population paradigm and all the elegant genetic work that has sprung from it has delivered a mountain of descriptive information with only a molehill of useful management options for real world problems. Many will disagree with my conclusion, and it is clear that conservation genetics is a major growth industry. That is all well and good but my question remains as to its influence on the solution of current conservation problems (Caro 2008; Hutchings 2015; Mattsson et al. 2008). Conservation genetic papers predicting extinctions in 100 years or more based on low levels of genetic variation are not scientifically testable and rely on a law of conservation genetics that is riddled with exceptions (Nathan et al. 2015; Robinson et al. 2016). Do we need more untestable hypotheses in conservation biology?

Caro, T. 2008. Decline of large mammals in the Katavi-Rukwa ecosystem of western Tanzania. African Zoology 43(1): 99-116. doi:10.3377/1562-7020(2008)43[99:dolmit]2.0.co;2.

Caughley, G. 1994. Directions in conservation biology. Journal of Animal Ecology 63: 215-244. doi: 10.2307/5542

Hutchings, J.A. 2015. Thresholds for impaired species recovery. Proceedings of the Royal Society. B, Biological sciences 282(1809): 20150654. doi:10.1098/rspb.2015.0654.

Mattsson, B.J., Mordecai, R.S., Conroy, M.J., Peterson, J.T., Cooper, R.J., and Christensen, H. 2008. Evaluating the small population paradigm for rare large-bodied woodpeckers, with Implications for the Ivory-billed Woodpecker. Avian Conservation and Ecology 3(2): 5. http://www.ace-eco.org/vol3/iss2/art5/

Nathan, H.W., Clout, M.N., MacKay, J.W.B., Murphy, E.C., and Russell, J.C. 2015. Experimental island invasion of house mice. Population Ecology 57(2): 363-371. doi:10.1007/s10144-015-0477-2.

Robinson, J.A., Ortega-Del Vecchyo, D., Fan, Z., Kim, B.Y., and vonHoldt, B.M. 2016. Genomic flatlining in the endangered Island Fox. Current Biology 26(9): 1183-1189. doi:10.1016/j.cub.2016.02.062.

Does Forestry Make Money – Part 2

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About 2 years ago I wrote a blog asking the simple question of whether the forest industry in British Columbia makes money or whether it is operational only because of subsidies and the failure to recognize that biodiversity and ecosystem services could be valuable. A recent report from the research group in the Fenner School of the Australian National University has put the spotlight on the mountain ash forests of the Central Highlands of Victoria to answer this question for one region of southern Australia. I summarize their findings from their report (Keith et al. 2016) that you can access from the web address given below.

The ANU research group chose the Central Highlands study area because it included areas with controversial land use activities. The study area of 7370 sq km contains a range of landscapes including human settlements, agricultural land, forests, and waterways, and is used for a variety of activities including timber production, agriculture, water supply and recreation. It is also home to a range of species, including the endemic and critically endangered Leadbeater’s Possum. These activities and their use of ecosystems can be either complementary or conflicting. Managing the various activities within the region is therefore complex and requires evaluation of the trade-offs between different land uses and users, an issue common to forestry areas around the world.

The accounting structure (System of Environmental-Economic Accounting) which is used by the United Nations is described in more detail in the report. Both economic and ecological data are needed to produce ecosystem accounts and these sources of data must be integrated to gain an overall picture of the system. This integration of ecosystem services with traditional cash crops is the key to evaluating an area for all of its values to humans. In this particular area the provisioning of water to cities is a key economic benefit provided by this particular area. The following table from their report puts all these accounts together for the Central Highlands of Victoria:

Table 5. Economic information for industries within the study region in 2013-14
Agriculture Native Forestry Water supply Tourism
Area of land used (ha) 96,041a 324,380b 115,149c 737,072d
Sale of products ($m) 474 49 911 485
Industry valued added ($m) 257 9 233 260
Ecosystem services ($m) 121 15 101 42
Sale of products ($ ha-1) 4918 151 7911 659
Industry value added ($ ha-1) 2667 29 2023 353
Ecosystem services ($ ha-1) 1255 46 877 57

a area of agricultural land use
b area of native forest timber production
c area of water catchments
d total area of study region

The key point in this table is that the value-added per ha of forestry is $29 per ha per year. The equivalent value for water is $2033 per ha per year – or 70 times more, and the value added for agriculture is about 90 time more than that of forestry. The value-added value for tourism is $350 per ha per year, about 12 times more than that of forestry. None of this takes into account any potential government subsidies to these industries, and none involves directly the endangered species in the landscape. Three main points emerge from this analysis:

  1. In 2013-14, the most valuable industries in the region were tourism ($260 million), agriculture ($257 million), water supply ($233 million) and forestry ($9 million). This is as measured by the estimated industry value added (the contribution to GDP).
  2. In 2013-14, the most valuable ecosystem services in the region were food provisioning ($121 million), water provisioning ($101 million), cultural and recreation services ($42 million).
  3. At a carbon price of $12.25 per ton (the average price paid by the Commonwealth in 2015), the potential ecosystem service of carbon sequestration ($20 million) was more valuable than the service of timber provisioning ($15 million).

The main implications from the report for this large geographical area are three:

  • The benefits from tourism, agriculture, and water supply are large, while those from forestry are comparatively small. There is a potential for income from carbon sequestration.
  • The activities of tourism, agricultural and water supply industries are complimentary and may be combined with biodiversity conservation and carbon sequestration.
  • Timber harvesting in native forests needs to better account for the occurrence of fires and can be incompatible with species requirements for conservation.

The recent global interest in both climate change and species conservation has pushed this type of analysis to uncover the complementary and conflicting activities of all major global industries. Replacing the conventional GDP of a country or a region with a measure that takes into account the changes in the natural capital including gains and losses is a necessary step for sustainability (Dasgupta 2015, Guerry et al. 2015). This report from Australia shows how this goal of replacing the current GDP calculation with a green GDP can be done in specific areas. Much of biodiversity conservation hinges on these developments.

Dasgupta, P. 2015. Disregarded capitals: what national accounting ignores. Accounting and Business Research 45(4): 447-464. doi: 10.1080/00014788.2015.1033851.

Guerry, A.D., et al. 2015. Natural capital and ecosystem services informing decisions: From promise to practice. Proceedings of the National Academy of Sciences 112(24): 7348-7355. doi: 10.1073/pnas.1503751112.

Keith, H., Vardon, M., Stein, J., Stein, J., and Lindenmayer, D. 2016. Exzperimental Ecosystem Accounts for the Central Highlands of Victoria. Australian National University, Fenner School of Environment and Society. 22 pp. Available from:
http://fennerschool-associated.anu.edu.au/documents/CLE/VCH_Accounts_Summary_FINAL_for_pdf_distribution.pdf

On Critical Questions in Biodiversity and Conservation Ecology

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Biodiversity can be a vague concept with so many measurement variants to make one wonder what it is exactly, and how to incorporate ideas about biodiversity into scientific hypotheses. Even if we take the simplest concept of species richness as the operational measure, many questions arise about the importance of the rare species that make up most of the biodiversity but so little of the biomass. How can we proceed to a better understanding of this nebulous ecological concept that we continually put before the public as needing their attention?

Biodiversity conservation relies on community and ecosystem ecology for guidance on how to advance scientific understanding. A recent paper by Turkington and Harrower (2016) articulates this very clearly by laying out 7 general questions for analyzing community structure for conservation of biodiversity. As such these questions are a general model for community and ecosystem ecology approaches that are needed in this century. Thus it would pay to look at these 7 questions more closely and to read this new paper. Here is the list of 7 questions from the paper:

  1. How are natural communities structured?
  2. How does biodiversity determine the function of ecosystems?
  3. How does the loss of biodiversity alter the stability of ecosystems?
  4. How does the loss of biodiversity alter the integrity of ecosystems?
  5. Diversity and species composition
  6. How does the loss of species determine the ability of ecosystems to respond to disturbances?
  7. How does food web complexity and productivity influence the relative strength of trophic interactions and how do changes in trophic structure influence ecosystem function?

Turkington and Harrower (2016) note that each of these 7 questions can be asked in at least 5 different contexts in the biodiversity hotspots of China:

  1. How do the observed responses change across the 28 vegetation types in China?
  2. How do the observed responses change from the low productivity grasslands of the Qinghai Plateau to higher productivity grasslands in other parts of China?
  3. How do the observed responses change along a gradient in the intensity of human use or degradation?
  4. How long should an experiment be conducted given that the immediate results are seldom indicative of longer-term outcomes?
  5. How does the scale of the experiment influence treatment responses?

There are major problems in all of this as Turkington and Harrower (2016) and Bruelheide et al. (2014) have discussed. The first problem is to determine what the community is or what the bounds of an ecosystem are. This is a trivial issue according to community and ecosystem ecologists, and all one does is draw a circle around the particular area of interest for your study. But two points remain. Populations, communities, and ecosystems are open systems with no clear boundaries. In population ecology we can master this problem by analyses of movements and dispersal of individuals. On a short time scale plants in communities are fixed in position while their associated animals move on species-specific scales. Communities and ecosystems are not a unit but vary continuously in space and time, making their analysis difficult. The species present on 50 m2 are not the same as those on another plot 100 m or 1000 m away even if the vegetation types are labeled the same. So we replicate plots within what we define to be our community. If you are studying plant dynamics, you can experimentally place all plant species selected in defined plots in a pre-arranged configuration for your planting experiments, but you cannot do this with animals except in microcosms. All experiments are place specific, and if you consider climate change on a 100 year time scale, they are also time specific. We can hope that generality is strong and our conclusions will apply in 100 years but we do not know this now.

But we can do manipulative experiments, as these authors strongly recommend, and that brings a whole new set of problems, outlined for example in Bruelheide et al. (2014, Table 1, page 78) for a forestry experiment in southern China. Decisions about how many tree species to manipulate in what size of plots and what planting density to use are all potentially critical to the conclusions we reach. But it is the time frame of hypothesis testing that is the great unknown. All these studies must be long-term but whether this is 10 years or 50 years can only be found out in retrospect. Is it better to have, for example, forestry experiments around the world carried out with identical protocols, or to adopt a laissez faire approach with different designs since we have no idea yet of what design is best for answering these broad questions.

I suspect that this outline of the broad questions given in Turkington and Harrower (2016) is at least a 100 year agenda, and we need to be concerned how we can carry this forward in a world where funding of research questions has a 3 or 5 year time frame. The only possible way forward, until we win the Lottery, is for all researchers to carry out short term experiments on very specific hypotheses within this framework. So every graduate student thesis in experimental community and ecosystem ecology is important to achieving the goals outlined in these papers. Even if this 100 year time frame is optimistic and achievable, we can progress on a shorter time scale by a series of detailed experiments on small parts of the community or ecosystem at hand. I note that some of these broad questions listed above have been around for more than 50 years without being answered. If we redefine our objectives more precisely and do the kinds of experiments that these authors suggest we can move forward, not with the solution of grand ideas as much as with detailed experimental data on very precise questions about our chosen community. In this way we keep the long-range goal posts in view but concentrate on short-term manipulative experiments that are place and time specific.

This will not be easy. Birds are probably the best studied group of animals on Earth, and we now have many species that are changing in abundance dramatically over large spatial scales (e.g. http://www.stateofcanadasbirds.org/ ). I am sobered by asking avian ecologists why a particular species is declining or dramatically increasing. I never get a good answer, typically only a generally plausible idea, a hand waving explanation based on correlations that are not measured or well understood. Species recovery plans are often based on hunches rather than good data, with few of the key experiments of the type requested by Turkington and Harrower (2016). At the moment the world is changing rather faster than our understanding of these ecological interactions that tie species together in communities and ecosystems. We are walking when we need to be running, and even the Red Queen is not keeping up.

Bruelheide, H. et al. 2014. Designing forest biodiversity experiments: general considerations illustrated by a new large experiment in subtropical China. Methods in Ecology and Evolution, 5, 74-89. doi: 10.1111/2041-210X.12126

Turkington, R. & Harrower, W.L. 2016. An experimental approach to addressing ecological questions related to the conservation of plant biodiversity in China. Plant Diversity, 38, 1-10. Available at: http://journal.kib.ac.cn/EN/volumn/current.shtml

On Caribou and the Conservation Conundrum

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The central conundrum of conservation is the conflict between industrial development and the protection of biodiversity. And the classic example of this in Canada is the conservation of caribou. Caribou in the millions have ranged over almost all of Canada in the past. They are now retreating in much of the southern part of their range, have nearly gone extinct in the High Arctic, and are extinct on Haida Gwaii (Queen Charlotte Islands). The majority of populations with adequate data are dropping in numbers rapidly. The causes of their demise point to human habitat destruction from forestry, mining, oil and gas developments and roads (Festa-Bianchet et al. 2011). We march on with economic development, and caribou are in the way of progress.

The nexus of interactions underlying this crisis is reasonably well understood for boreal caribou and there is an extensive literature on the topic (Bergerud et al. 2007; Hervieux et al. 2013; Hervieux et al. 2014; Schaefer and Mahoney 2013; Wittmer et al. 2007). Caribou avoid human constructions like pipelines, mines, forestry operations, and roads. Forestry in particular opens up habitat that tends to favor deer and moose. Climate change makes winters less severe for deer. More prey makes more predators, and caribou are typically accidental, secondary prey from wolves that live largely off moose and deer. The habitats that humans open up with roads, seismic lines, and wellheads provide superhighways for wolves and other predators, so that predator access is greatly improved. Such access roads also allow hunters to access ungulates and potentially increase the harvest rate.

If predators are the key immediate factor reducing caribou populations, there seem to be two general solutions. Killing wolves is the most obvious management action, and much of wildlife management in North America has historically been based on the simple paradigm: “killing wolves is the answer, now what is the question?” But two problems arise. There are more predators than wolves (e.g. bears) and secondly killing wolves does not work very well (Hayes 2010). At best it seems to slow down the caribou decline at great expense, and it has to be continuous year after year because killing wolves increases the reproductive rate of those left behind and migration of wolves into the “control” area is rapid. So this management action becomes too expensive in the long run to work well and most people don’t want to see bears killed wholesale either. So the next option is to use fencing to protect caribou from contact with all predators. These fences could be on small areas into which pregnant female caribou are put in the spring to have their calves, and then released when the calves are a few months old and have a better chance of avoiding predators. Or the ultimate fence would be around hundreds of square kilometers to enclose a permanent caribou population with all the predators removed inside the fenced area. This would require continuous maintenance and is very costly. It turns caribou into a zoo animal, albeit on a large scale.

There is one other solution and that is to set aside very large areas of habitat that are not invaded by the forestry, mining, and oil industries, and to monitor the dynamics of caribou in these large reserves. Manitoba is apparently doing this, with reported success in stopping caribou declines.

Beyond these southern populations of caribou in the boreal forest zone, the problems of caribou population trends on the tundra are difficult to unravel, partly because of a lack of data arising from a shortage of funds (Gunn et al. 2011). Climate change is happening and the exact effects on tundra populations is unclear. Many barren-ground caribou herds show fluctuations in abundance with a period of about 50 years. Food supply exhaustion may be one factor in the fluctuations but harvesting is also involved. Local harvest data are often not recorded and with poor population data and poor harvest data we can rarely determine the trajectories of the herds or explain why they are changing in abundance. Peary caribou in the far north are suffering from climate change, rain events in winter that freezes their food supply of lichens under ice so they starve. No one knows how to alleviate the weather, and we only add to the problem with our greenhouse gas emissions. Peary caribou now survive in very low numbers but we cannot be sure that will continue.

All in all, we work hard to conserve large mammal ecosystems in tropical countries but seem far too unconcerned about our Canadian caribou heritage. To inform conservation actions, serious long-term population studies are sorely needed, including more frequent aerial census estimates for all the caribou herds, radio-collaring individuals for demographic data and movements, and complete harvesting data from all sources.

 

Bergerud, A.T., Dalton, W.J., Butler, H., Camps, L., and Ferguson, R. 2007. Woodland caribou persistence and extirpation in relic populations on Lake Superior. Rangifer 27(4): 57-78 (Special Issue No. 17). doi: http://dx.doi.org/10.7557/2.27.4.321

Festa-Bianchet, M., Ray, J.C., Boutin, S., Côté, S.D., and Gunn, A. 2011. Conservation of caribou (Rangifer tarandus) in Canada: an uncertain future. Canadian Journal of Zoology 89(5): 419-434. doi:10.1139/z11-025 .

Gunn, A., Russell, D., and Eamer, J. 2011. Northern caribou population trends in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 10. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 71 p. http://www.biodivcanada.ca/default.asp?lang=En&n=137E1147-1

Hayes, B. (2010) Wolves of the Yukon. Wolves of the Yukon Publishing, Smithers, B.C. ISBN: 978-1-4566-1047-0

Hervieux, D., Hebblewhite, M., DeCesare, N.J., Russell, M., Smith, K., Robertson, S., and Boutin, S. 2013. Widespread declines in woodland caribou (Rangifer tarandus caribou) continue in Alberta. Canadian Journal of Zoology 91(12): 872-882. doi:10.1139/cjz-2013-0123.

Hervieux, D., Hebblewhite, M., Stepnisky, D., Bacon, M., and Boutin, S. 2014. Managing wolves (Canis lupus) to recover threatened woodland caribou (Rangifer tarandus caribou) in Alberta. Canadian Journal of Zoology 92(12): 1029-1037. doi:10.1139/cjz-2014-0142 .

Schaefer, J.A., and Mahoney, S.P. 2013. Spatial dynamics of the rise and fall of caribou (Rangifer tarandus) in Newfoundland. Canadian Journal of Zoology 91(11): 767-774. doi:10.1139/cjz-2013-0132 .

Wittmer, H.U., McLennan, B.N., Serrouya, R., and Apps, C.D. 2007. Changes in landscape composition influence the decline of a threatened caribou population. Journal of Animal Ecology 76: 568-579. doi: 10.1111/j.1365-2656.2007.01220.x

On Gravity Waves and the 1%

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The news this week has been all about the discovery of gravity waves and the great triumphs of modern physics to understand the origin of the universe. There is rather less news on the critical ecological problems of the Earth – of agricultural sustainability, biodiversity collapse, pollution, climate change – not to mention the long recognized economic problems of poverty and inequality, globally and within our own countries. All of these issues converge to the questions of resource allocations by our governments that have failed to assess priorities on many fronts. Many see this but have little power to change the system that is continually moving to save and improve the fortunes of the 1% to the detriment of most people.

In scientific funding there has always been a large bias in favor of the physical sciences, as I have commented on previously, and the question is how this might be publicized to produce  a better world. I suggest a few rules for scientific funding decisions both by governments and by private investors.

Rule 1: For maximizing scientific utility for the biosphere including humans, we require a mix of basic and applied science in every field. Whether this mix should be 50:50, 30:70, or 70:30 should be an item for extended discussion with the implicit assumption that it could differ in different areas of science.

Rule 2: Each major area of science should articulate its most important issues that must be addressed in the short term and the long term (>50 years). For biodiversity, as an example, the most important short term problem is to minimize extinctions while the most important long term problem might be to maintain genetic variability in populations.

Rule 3: The next step is most critical and perhaps most controversial: What are the consequences for the Earth and its human population if the most important issue in any particular science is not solved or achieved? If the required experiments or observations can be delayed for 30 (or 50) years, what will it matter?

If we could begin to lay out this agenda for science, we could start a process of ranking the importance of each of the sciences for funding in the present and in the long term. At the present time this ranking process is partly historical and partly based on extreme promises of future scenarios or products that are of dubious validity. There is no need to assume that all will agree, and I am sure that several steps would have to be designated to involve not only young and older scientists but also members of the business community and the public at large.

If this agenda works, I doubt that we would spend quite so much money on nuclear physics and astronomy and we might spend more money on ocean science, carbon budgets, and sustainable agricultural research. This agenda would mean that powerful people could not push their point of view in science funding quite so freely without being asked for justification. And perhaps when budgets are tight for governments and businesses, the first people on the firing line for redundancy will not be environmental scientists trying their best to maintain the health of the Earth for future generations.

So I end with 2 simple questions: Could gravity waves have waited another 100 years for discovery? What is there that cannot wait?

(Finally, an apology. I failed to notice that on a number of recent blogs the LEAVE A REPLY option was not available to the reader. This was inadvertent and somehow got deleted with a new version of the software. I should have noticed it and it is now corrected on all blogs.)