C1 Hall

Directions in Conservation Biology Revisited


Erlend B. Nilsen
Diana Bowler
John Linnell


In any scientific endeavour, the object is to understand how the natural world works. In applied sciences this endeavour is further motivated by a need to predict the effectiveness of management interventions based on scientific data, results or theories.. Conservation biology, which is at its roots an applied science emerged as a science in the 1980’s. Although it profits from older disciplines such as ecology, it is still a relatively young science. In his seminal paper from 1994, G. Caughley (Directions in Conservation Biology, J. Anim. Ecol. 63: 215-244) identified two paradigms in conservation biology. He proposed that while the small population paradigm (concerned with the viability of small populations) is theory laden, the declining population paradigm (concerned with declining populations) was scant of theoretical basis and was carried out mainly as a series of case studies often with limited general interest. To which extent these statements are still justified as conservation biology as a scientific field has grown older remains largely unstudied.

In this talk, we will present the results from a review based on a random sample of papers published in the main conservation and applied ecology journals across the last decades. We will limit our review to studies that present (and analyse) empirical data from the natural world. Thus, the papers we include and that broadly falls within the frames of the ecological disciplines, and we disregard papers that belong mainly within the social sciences or forum articles. We first present a summary of the relative frequency of experimental versus observational/correlative studies. The we will then focus on how frequently individual studies mainly i) describe associations among variables, ii) document causal effects, or iii) mainly present updated parameter estimates (e.g. demographic rates from new study sites). Furthermore, we assess the frequency of clearly stated hypothesis from which logical and testable predictions are deduced. When hypothesis are present we assess their generality and boldness in terms of taxonomic and environmental coverage. Finally, for the papers that state clearly testable predictions we assess to which extent they make formal statistical assessments of the resulting models’ predictive capabilities.

The ultimate goal of conservation biology is to make a difference in the real world, but the impact of science on conservation outcomes is often hotly contested. We argue that conservation biologists ought to pay attention the philosophy of science and the philosophy of biology, and that a better understanding of how conservation biology as a science is carried out is timely.