Best Available Science and the Limitations of using science to make decisions on wildlife conservation and the dispute over Dingoes in Australia

​Best Available Science and the Limitations of using science to make decisions on wildlife conservation and the dispute over Dingoes in Australia
 
In my Wildlife Politics book, I devote a chapter to exploring the role that science plays in wildlife conservation decisionmaking. As is widely known, the ESA (Endangered Species Act) in the U.S. and several other major laws and international agreements specify that the best available science should be employed in making conservation decisions. Consequently, science has played a key role in wildlife policymaking, more so than in most policy areas. However, my chapter explores how the role of science is often limited. In several cases I document such as policies over bison leaving Yellowstone, politics trumps science.  However, the other limitations of science impact are due to uncertainties that are inherent in the scientific process itself such as inadequate or questionable data, key assumptions that dictate the results of models that are now regularly employed in science, and values that underlie scientific conclusions.  I illustrate how often scientists disagree among themselves over conclusions—these disagreements may be due to differences in assumptions and methods but can also be affected by their values and professional roles that they play.  For example, I discuss how Alaskan Department of Fish and Game researchers came to very different conclusions from environmentalist researchers concerning the impacts of grizzlies and wolves on game.  One of the areas that I discuss in depth is the controversy over the cascade effects of predators such as wolves—many researchers have focused on how predators such as wolves and otters may contribute to diversity by their take of prey and thus moderating the impacts of herbivores and sea urchins respectively.  However, in the book, I demonstrate the complexity of science that makes it difficult to draw clear conclusions about the impacts of predators.
 
Recently, the controversy over predator effects has emerged against, this time concerning dingoes in Australia.  Morris and Letnic in an article titled “Removal of an apex predator initiates a trophic cascade that extends from herbivores to vegetation and the soil nutrient pool” http://rspb.royalsocietypublishing.org/content/284/1854/20170111  conducted a study with some quasi-experimental controls to show that dingoes have had a positive effect on the amount of “soil nutrient level” by controlling populations of kangaroo.  The “quasi-experiment” occurred because a “dingo proof” fence had been constructed so that the researchers compared the dingo-occupied areas with dingo-less areas.  They concluded that there was evidence of positive trophic cascades that would assist biodiversity.  Another Australian researcher, Benjamin Allen, has published articles questioning the cascade effects hypothesis for dingoes such as in the following article: Allen, Benjamin A. A comment on the distribution of historical and contemporary livestock grazing across Australia: Implications for using dingoes for biodiversity Conservation. Ecological Management & Restoration, 12(1), April 2011, 26-30. He points out that can influence faunal declines including the amount and nature of livestock grazing, fire, disease, “introduce herbivores, and land clearing.” Thus effects attributed to the presence (or absence) of dingoes may actually be due to “landscape productivity” or “timing of rainfall.” He cautions that encouraging the spread of dingoes to spur cascades could be dangerous—dingoes could actually be a threat to the endangered species, not their saviors.
 
Another article by Kuijper et al. titled “Paws without claws? Ecological effects of large carnivores in anthropogenic landscapes” discusses other complicating factors that make it difficult to determine the effects of predators. In particular, they discuss how the presence and activities of humans affects the results of predators.  They discuss, for example, how in countries such as Sweden, human  takes of carnivores keeps their populations much reduced and thus it is questionable whether this small population of carnivores can affect prey species.  They also discuss how “agriculture” and “silviculture” along with “supplementary feeding” can allow “prey” to grow “beyond carnivore control.”  In addition, they state that human hunting very directly influences carnivore hunting location and thus push carnivore take of prey into remote locations.  Consequently, they conclude that “predator-prey interactions” are “highly complex-dependent” and thus it is difficult to arrive at a “general conclusion about the current or future effects of predators.” 
 
The above studies beg a discussion of how are policymakers to arrive at a policy based on “best science available” when there is uncertainty about causal factors?  I illustrate this dilemma in my Wildlife Politics book in cases involving wolverines in the U.S. as well as wolves.  What happens is that decisionmakers often rely on the judgments of professional wildlife researchers, realizing that their conclusions are based on imperfect knowledge that could change in the future with new studies. Critics of these decisions sometimes label these judgments as “junk science.”  The alternative is to rely on the values and preferences of elected or appointed officials whose opinions may be affected by stakeholders (e.g., hunters, ranchers, extractive industries, etc.)  Despite these limitations of science, overall, science has had a major impact on wildlife conservation policymaking.  Still, concerning he most controversial decisions, especially those involving predators who are threatening to humans, politics plays an important and often, the dominating, role.