Classical approaches to assessing the sustainability of bushmeat hunting in tropical forests have serious limitations, according to van Vliet et al. (2015); they therefore suggest that “resilience approaches” are needed in order to incorporate complexity in such sustainability assessments. As examples of such approaches they list companion models, fuzzy-logic cognitive mapping, and multi-agent-based models. The authors, however, fail to distinguish between assessing sustainability and the much broader quest of achieving sustainability. According to the authors, companion modeling and fuzzy-logic cognitive mapping are, respectively, methods for supporting collective decision-making and for collaboratively building conceptual models. These methods may well have a potential to contribute to achieving sustainability, but assessing sustainability is something else.
Sustainability as a scientific concept dates back over 200 years, when it was described in German forestry literature (e.g., Hartig 1804) as the capacity of any level of timber extraction to endure in time. During the 20th century, this concept also became widely adopted within wildlife and fishery sciences and management. However, as described by Salo et al. (2014, pp. 32–36), towards the end of the 20th century the term sustainability entered the arena of political discourse, where it often lost its original meaning related to durability in time and instead often became a normative concept, synonymous for anything “good”, “desirable”, or “morally right”, particularly when used in compound terms such as “social sustainability” and similar. Unfortunately, this practice also spilled over into the academic literature. The paper of van Vliet et al. is, thus, just one more of many papers where this loss of clarity of concepts leads to a corresponding loss of clarity of thought.
Research on bushmeat hunting can have a wide variety of specific focuses. The call of van Vliet et al. for increased attention to social and economic aspects of tropical forest hunting is pushing on open doors. In their review of the literature, the authors themselves provide numerous examples of research that has related hunting practices to, for example, bushmeat markets, prices, demographic change, changing livelihood opportunities, household size, nutrition and food security, and culture. The list could be made much longer, including, for example, the costs of supplies and labor (Hofer et al., 2000, Sirén and Wilkie 2015), income and wealth (Wilkie et al. 2005; Sirén et al. 2006; Godoy et al. 2010; Vasco and Sirén, submitted to Animal Conservation), changes in hunting technology (Hames 1979, Alvard 1995, Koster 2009, Sirén 2014), and common property governance (Osemeobo, 1991, Barrett et al. 2001, Bremner and Lu 2006, Sirén 2006).
Furthermore, van Vliet et al. paint a false picture of what wildlife management efforts in tropical forests are all about. In fact, maximum sustained yield (MSY) is seldom, if ever, the goal. This is not only because harvesting at MSY is economically suboptimal when search costs are significant (Milner-Gulland and Mace 1998, Clark 2010, Salo et al. 2014), but also because the focus is not at all on “seeking optimal states”. Usually it is even less a realistic option to “ban hunting altogether” according to “precautionary principles”. This is because the societal context in these regions typically is such that resource governance constitutes a far harder challenge than resource management (see Salo et al. 2014, chapters 15 and16). Therefore, a reasonably realistic goal in the short and medium terms must, in most cases, be to just make a bad situation a bit less bad.
For that purpose, such in-situ participatory processes and adaptive management processes that van Vliet et al. propose are indeed more likely to directly affect sustainability of hunting in the right direction than is research narrowly aimed at the production of journal articles. In order to know whether this actually happens, though, there will still be a need for assessing sustainability through quantitative empirical methods. The methods available are constantly improving. van Vliet et al. themselves list a wide variety of such methods—including comparisons of before and after, or between different sites subject to different hunting intensity—as well as demographic models, population trend methods, and harvest-based or market-based indicators, to which I would like to add methods based on evaluating spatial gradients of harvest (Sirén et al. 2004, Sirén and Parvinen 2015). Multi-agent models, as suggested by van Vliet et al. (2015), may also have potential; although, similar to many other methods, they suffer from the difficulty of estimating ingoing model parameters with the needed precision.
This work was funded by the Prometeo Project of the Secretariat for Higher Education, Science, Technology and Innovation of the Republic of Ecuador. Thanks to Matti Salo for commenting on an earlier version of the manuscript.