Refining area of occupancy to address the modifiable areal unit problem in ecology and conservation

The ‘modifiable areal unit problem’ is prevalent across many aspects of spatial analysis within ecology and conservation. The problem is particularly manifest when calculating metrics for extinction risk estimation, for example, area of occupancy (AOO).Although embedded into the International Union for the Conservation of Nature (IUCN) Red List criteria, AOO is often not used or is poorly applied. Here we evaluate new and existing methods for calculating AOO from occurrence records and present a method for determining the minimum AOO using a uniform grid. We evaluate the grid cell shape, grid origin and grid rotation with both real-world and simulated data, reviewing the effects on AOO values, and possible impacts for species already assessed on the IUCN Red List. We show that AOO can vary by up to 80% and a ratio of cells to points of 1:1.21 gives the maximum variation in the number of occupied cells. These findings potentially impact 3% of existing species on the IUCN Red List, as well as species not yet assessed. We show that a new method that combines both grid rotation and moving grid origin gives fast, robust and reproducible results and, in the majority of cases, achieves the minimum AOO. As well as reporting minimum AOO, we outline a confidence interval which should be incorporated in to existing tools that support species risk assessment. We also make further recommendations for reporting AOO and other areal measurements within ecology, leading to more robust methods for future species risk assessment

Ghost crab burrow density at Watamu Marine National Park: an indicator of the impact of urbanisation and associated disturbance?

Ghost crab (Ocypode species) burrow densities have previously been used as an indicator of anthropogenic impact. This study aimed to assess the burrow density of Ocypode species (O. ryderi and O. cordimanus) at four sites across Watamu Marine National Park, Kenya. Two sites were in front of hotel complexes (denoting a high degree of urbanisation), and two were in front of residential housing among coastal scrub (denoting a low degree of urbanisation). The findings reveal significantly higher burrow densities at sites in front of residential housing, which was the less developed area. This provides further evidence that Ocypode burrow densities can be used, where other methods would be impractical, to estimate the impact of some human activities along beach fronts, such as at Watamu Marine National Park

Exceptional responders in conservation.

Conservation operates within complex systems with incomplete knowledge of the system and the interventions utilized. This frequently results in the inability to find generally applicable methods to alleviate threats to Earth's vanishing wildlife. One approach used in medicine and the social sciences has been to develop a deeper understanding of positive outliers. Where such outliers share similar characteristics, they may be considered exceptional responders. We devised a 4-step framework for identifying exceptional responders in conservation: identification of the study system, identification of the response structure, identification of the threshold for exceptionalism, and identification of commonalities among outliers. Evaluation of exceptional responders provides additional information that is often ignored in randomized controlled trials and before-after control-intervention experiments. Interrogating the contextual factors that contribute to an exceptional outcome allow exceptional responders to become valuable pieces of information leading to unexpected discoveries and novel hypotheses

Predicting intervention priorities for wildlife conflicts

There is growing interest in developing effective interventions to manage socially‐ and environmentally‐damaging conservation conflicts. Recent studies have identified a wide variety of different intervention strategies in various contexts but the reasons why one type of intervention is chosen over another remain underexplored. In this international study we surveyed conservation researchers and practitioners (N = 427) to explore how the characteristics of conflicts and characteristics of decision‐makers influence conflict recommendations. Using a fully‐factorial design, we experimentally manipulated three aspects of eight different conflict scenarios – the development status of the country, the conflict framing, and whether wildlife killing was illegal – and recorded whether respondents prioritised one of five intervention types: wildlife impact reduction, awareness, enforcement, economic incentives or stakeholder engagement. We also recorded information on respondents’ demographic and disciplinary backgrounds. Stakeholder‐based interventions were recommended most often in the survey and in written feedback. However, fitting multinomial mixed logit models with no missing scenarios (N = 411), we find that recommendations are influenced by small changes in the details of conflict, and differ according to respondent characteristics. Enforcement and awareness interventions are prioritised more in conflicts in more highly developed nations and by respondents with more natural‐science backgrounds and less experience of conflicts. Contrastingly, economic interventions are prioritised more when wildlife killing is described as illegal. Respondent age, gender and the development status of their home country also predicted some intervention decisions. Further interrogating the influences shaping conservation decision‐making will help towards developing evidence‐informed interventions

Accounting for complementarity to maximize monitoring power for species management

To choose among conservation actions that may benefit many species, managers need to monitor the consequences of those actions. Decisions about which species to monitor from a suite of different species being managed are hindered by natural variability in populations and uncertainty in several factors: the ability of the monitoring to detect a change, the likelihood of the management action being successful for a species, and how representative species are of one another. However, the literature provides little guidance about how to account for these uncertainties when deciding which species to monitor to determine whether the management actions are delivering outcomes. We devised an approach that applies decision science and selects the best complementary suite of species to monitor to meet specific conservation objectives. We created an index for indicator selection that accounts for the likelihood of successfully detecting a real trend due to a management action and whether that signal provides information about other species. We illustrated the benefit of our approach by analyzing a monitoring program for invasive predator management aimed at recovering 14 native Australian mammals of conservation concern. Our method selected the species that provided more monitoring power at lower cost relative to the current strategy and traditional approaches that consider only a subset of the important considerations. Our benefit function accounted for natural variability in species growth rates, uncertainty in the responses of species to the prescribed action, and how well species represent others. Monitoring programs that ignore uncertainty, likelihood of detecting change, and complementarity between species will be more costly and less efficient and may waste funding that could otherwise be used for management. Contabilizacion de la Complementariedad para Maximizar el Poder de Monitoreo para el Manejo de Especie

Establishing IUCN Red List Criteria for Threatened Ecosystems

The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature\u27s (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem\u27s extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012

Decision complacency and conservation planning

Article impact statement: : Conservation planners must use systematic decision?making tools and evidence to guide their decisions