Preferences elicitation can be a challenging exercise for citizens participating in assessment surveys. It is even more challenging when it comes to complex and unfamiliar ecosystems and the threatened ecosystem services they provide. Making people aware of the characteristics of the ecosystem services being valued is determinant for the assessment process. We investigated the impact of familiarity and academic information supply on people's preferences for twenty selected ecosystem services of French Mediterranean coastal lagoons. The results show that regardless of familiarity and information supply, there is a strong consensus about the highest importance of regulation and maintenance ecosystem services as well as environmental education and research opportunity ecosystem services. By contrast, nine of the cultural ecosystem services, together with two provisioning ecosystem services showed heterogeneous preferences among the different citizen groups. Using a combination of descriptive and inferential statistics these eleven ecosystem services split up into three clusters characterized as (i) contemplative leisure, (ii) heritage, and (iii) consumptive activities. Familiarity and academic information supply had a strong impact on the preferences for these three clusters of ecosystem services.

Efficient biodiversity management strategies aim to allocate conservation efforts so as to maximize diversity in ecological systems. Toward this end, defining a diversity criterion is an important but challenging task, as several different indices can be used as biodiversity measures. This paper elicits and compares two criteria for biodiversity conservation based on indices stemming from different disciplines: Weitzman's index in economics and Rao's index in ecology. These indices use different approaches to combine information about measures of (1) the probability distributions of the species that are present in an ecosystem (i.e. survival probabilities) and (2) the degree of dissimilarity between these species. As an important step toward in situ conservation criteria, we add to these elements information about (3) the ecological interactions that take place between species. Considering a simple three-species ecosystem, we show that criterion choice has palpable policy implications, as it can sometimes lead to divergent management recommendations. We disentangle the roles played by elements (1), (2) and (3) in the ranking of outcomes, which allows us to highlight several specificities of the two criteria. An important result is that, other things being equal, Weitzman's in situ ranking tends to favor robust species that are least concerned with extinction, while Rao's in situ ranking generally gives priority to more vulnerable species that are closer to extinction.

Biological invasions entail massive biodiversity losses and tremendous economic impacts that justify significant management efforts. Because the funds available to control biological invasions are limited, there is a need to identify priority species. In this paper, we first review current invasive species prioritization methods and explicitly highlight their strengths and pitfalls. We then construct a cost–benefit optimization framework that offers the theoretical foundations of a simple method for the management of multiple invasive species under a limited budget. We provide an algorithm to operationalize this framework and render explicit the assumptions required to satisfy the management objective.

In this paper, we investigate the determinants of private flood mitigation in France. We conducted a survey among 331 inhabitants of two flood-prone areas and collected data on several topics, including individual flood mitigation, risk perception, risk experience, and sociodemographic characteristics. We estimate discrete choice models to explain either the precautionary measures taken by the household, or the intention to undertake such measures in the future. Our results confirm that the Protection Motivation Theory is a relevant framework to describe the mechanisms of private flood mitigation in France, highlighting in particular the importance of threat appraisal and previous experience of floods. Some sociodemographic features also play a significant role in explaining private flood mitigation. We also observed that respondents who had already taken precautionary measures have a lower perception of the risk of flooding than respondents who planned to implement such measures at the time of the survey. This result can be explained by the existence of a feedback effect of having taken precautionary measures on risk perception. If subsequent studies support this assumption, it would imply that intended measures, rather than implemented ones, should be examined to explore further the determinants of private flood mitigation.