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To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2006.00560.x Byline: ATTE MOILANEN (*), BRENDAN A. WINTLE ([dagger]), JANE ELITH ([dagger]), MARK BURGMAN ([dagger]) Keywords: distribution discounting; distribution smoothing; information-gap decision theory; reserve-network design; site-selection algorithm; spatial reserve design; zonation Abstract: Abstract: Methods for reserve selection and conservation planning often ignore uncertainty. For example, presence-absence observations and predictions of habitat models are used as inputs but commonly assumed to be without error. We applied information-gap decision theory to develop uncertainty analysis methods for reserve selection. Our proposed method seeks a solution that is robust in achieving a given conservation target, despite uncertainty in the data. We maximized robustness in reserve selection through a novel method, 'distribution discounting,' in which the site- and species-specific measure of conservation value (related to species-specific occupancy probabilities) was penalized by an error measure (in our study, related to accuracy of statistical prediction). Because distribution discounting can be implemented as a modification of input files, it is a computationally efficient solution for implementing uncertainty analysis into reserve selection. Thus, the method is particularly useful for high-dimensional decision problems characteristic of regional conservation assessment. We implemented distribution discounting in the zonation reserve-selection algorithm that produces a hierarchy of conservation priorities throughout the landscape. We applied it to reserve selection for seven priority fauna in a landscape in New South Wales, Australia. The distribution discounting method can be easily adapted for use with different kinds of data (e.g., probability of occurrence or abundance) and different landscape descriptions (grid or patch based) and incorporated into other reserve-selection algorithms and software. Abstract (Spanish): Analisis de Incertidumbre para la Seleccion de Reservas a Escala Regional Resumen: Los metodos para la seleccion de reservas y la planificacion de conservacion a menudo ignoran la incertidumbre. Por ejemplo, las observaciones de presencia-ausencia y las predicciones de los modelos de habitat son utilizadas como datos, pero comunmente se asume que no tienen errores. Aplicamos la teoria de decisiones con vacio de informacion para desarrollar metodos de analisis de incertidumbre para la seleccion de reservas. El metodo que proponemos busca una solucion que sea robusta en el logro de una determinada meta de conservacion, a pesar de la incertidumbre en los datos. Maximizamos la robustez de la seleccion de reservas mediante un metodo novedoso, 'descuento de la distribucion,' en el que la medida del valor de conservacion de un sitio o especie (relacionado con las probabilidades de ocupacion especificas) era penalizado por una medida de error (en nuestro estudio, relacionado con la precision de la prediccion estadistica). Debido a que el descuento de distribucion se puede implementar como una modificacion de los archivos de datos, es una eficiente solucion computable para la inclusion del analisis de incertidumbre en la seleccion de reservas. Por lo tanto, el metodo es particularmente util para problemas de decisiones de altas dimensiones caracteristicos de la evaluacion regional de la conservacion. Implementamos el descuento de distribucion en el algoritmo zonation para la seleccion de reservas que produce una jerarquia de prioridades de conservacion en el paisaje. Lo aplicamos a la seleccion de reservas para siete faunas en un paisaje en New South Wales, Australia. El metodo de descuento de la distribucion se puede adaptar facilmente a diferentes tipos de algoritmos (basados en cuadriculas o parches) y se puede incorporar a otros algoritmos y datos de software (e.g., probabilidad de ocurrencia o abundancia) para la seleccion de reservas, asi como a diferentes descripciones del paisaje. Author Affiliation: (*)Metapopulation Research Group, Department of Biological and Environmental Sciences, P.O. Box 65, FI-00014, University of Helsinki, Finland, emailatte.moilanen@helsinki.fi ([dagger])School of Botany, University of Melbourne, Parkville, VIC 3010, Australia Article History: Paper submitted September 11, 2005; revised manuscript accepted March 27, 2006.

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2006.00525.x Byline: FIONA FIDLER (*s.), MARK A. BURGMAN (*), GEOFF CUMMING ([dagger]), ROBERT BUTTROSE (*), NEIL THOMASON ([double dagger]) Keywords: Bayesian methods; confidence intervals; statistical power; statistical significance testing Abstract: Abstract: Over the last decade, criticisms of null-hypothesis significance testing have grown dramatically, and several alternative practices, such as confidence intervals, information theoretic, and Bayesian methods, have been advocated. Have these calls for change had an impact on the statistical reporting practices in conservation biology? In 2000 and 2001, 92% of sampled articles in Conservation Biology and Biological Conservation reported results of null-hypothesis tests. In 2005 this figure dropped to 78%. There were corresponding increases in the use of confidence intervals, information theoretic, and Bayesian techniques. Of those articles reporting null-hypothesis testing-which still easily constitute the majority-very few report statistical power (8%) and many misinterpret statistical nonsignificance as evidence for no effect (63%). Overall, results of our survey show some improvements in statistical practice, but further efforts are clearly required to move the discipline toward improved practices. Abstract (Spanish): Impacto de la Critica a las Pruebas de Significancia de Hipotesis Nula en las Practicas de Reporte Estadistico en Biologia de la Conservacion Resumen: En la ultima decada, las criticas a la prueba de significancia estadistica han crecido dramaticamente, y se han propuesto varias practicas alternativas, como los intervalos de confianza, teoria de la informacion y metodos Bayesianos. Han tenido impacto estos llamados al cambio sobre las practicas de reporte estadistico en biologia de la conservacion? En 200 y 2001, 92% de los articulos muestreados en Conservation Biology y Biological Conservation reportaron pruebas de hipotesis nulas. En 2005 esta cifra cayo a 78%. Hubo incrementos correspondientes en el uso de intervalos de confianza, teoria de la informacion y tecnicas Bayesianas. De los articulos que reportan pruebas de hipotesis nulas-que facilmente aun constituyen la mayoria-muy pocos (8%) reportan el poder estadistico y muchos mal interpretan la no significancia estadistica como evidencia de no efecto (63%). En general, los resultados de nuestro muestreo muestran algunas mejorias en la practica estadistica, pero claramente se requieren mayores esfuerzos para que la disciplina tenga mejores practicas. Author Affiliation: (*)School of Botany, University of Melbourne, Victoria 3010, Australia ([dagger])School of Psychological Science, La Trobe University, Victoria 3086, Australia ([double dagger])Department of History and Philosophy of Science, University of Melbourne, Victoria 3010, Australia Article History: Paper submitted August 3, 2005; revised manuscript accepted February 6, 2006. Article note: (s.) email fidlerfm@unimelb.edu.au

The identification and prioritisation of natural values and the potential threats to them is an essential part of the management of parks and reserves by Parks Victoria, which regularly explores alternative ways to undertake and improve the efficiency of this process. Here we describe an application of ecological risk assessment techniques for identifying and analysing risks to natural values in the mallee national parks of north-western Victoria. Utilizing a workshop setting and multiple assessors, hazards were identified with the aid of a hazard matrix. A modification of the risk analysis protocol from the Australian Standard for Risk Management, AS/NZS 4360, was used to facilitate assessment by multiple participants and to capture the full range of their judgements so as to best characterise threats to natural values. An iterative process provided opportunity to resolve uncertainty due to linguistic ambiguity and vagueness, and genuine differences of opinion that remained were explicitly represented in the final ranking of the hazards. A fault tree was then used to explore the ecological complexities behind one particular issue of concern in the mallee parks.

Environmental management involves assessments of the costs and benefits of stochastic processes. Judgements about the likelihoods and consequences of these processes depend on a broad range of uncertainties, most of which are unacknowledged in current approaches to qualitative risk assessments such as the Australian standard (AS/NZS 4360-1999). This article outlines some of the major sources of uncertainty in ecological risk assessments and provides a case study of the magnitude of the uncertainty associated with subjective assessments. It demonstrates the extent to which uncertainties may be reduced by consideration of a few kinds of uncertainty. And it suggests alternative approaches to risk assessment that are valuable primarily for ensuring that debates are relatively transparent, internally consistent, and free of ambiguity.

We examined association patterns of wild, nonprovisioned pygmy chimpanzees in the central rain forest of Zaire. Associations among individuals within two communities (Hedons and Rangers) and one splinter group (Blobs) were discribed using two measures: the proportion of time spent together in parties, and the proportion of time spent in close proximity while feeding. Patterns were exposed using multivariate analysis and tested using nonparametric (Mantel) tests. Associations among females characterized the social interactions of both Hedons and Blobs. Associations among males, and between males and females, were common only for the Rangers. Parties of Blobs tended to be small (average size: 4), whereas parties of Hedons were of variable size (average: 7), and those of Rangers were predominantly large (average: 10). Thus, variation in association patterns corresponded loosely to differences in party size. Associations among females were most prevalent in small parties. By contract, associations among males and between males and females were more apparent in large parties. This intracommunity correlation of social organization and party size parallels differences between the Lomako and Wamba study sites. This relationship may reflect the importance of female alliances when food is limited and the ability of single males to monopolize small, but not large, parties of associated females.

Author(s): Barry W. Brook (corresponding author) [1, 2]; Julian J. O'Grady [1]; Andrew P. Chapman [1]; Mark A. Burgman [3]; H. Resit Akçakaya [4]; Richard Frankham [1] Population viability analysis [...]

Many governments aspire to evidence-based policy and practice. The predominant, conventional approaches to using experts are either to seek the advice of one highly regarded individual, or to convene a [...]

Statistical reporting process in environmental conservation programs is examined.

Three broadly used systematic conservation classification protocols are assessed for accuracy of extinction risk prediction, and causes of discrepancies are identified. Findings emphasize the importance adequate training and the representation of uncertainties in calculations and reports.

The rate of false absences for two species of forest owl and four species of arboreal marsupial based on eight repeat visits to fifty survey locations in southeastern Australia are examined. The results suggest that temperature, rainfall and habitat quality influenced the detectability of most species.

An evaluation of three different systems for calculating species extinction threat levels is presented. Positive correlations among the threat rankings were found among the three systems, and the rankings are linked with predicted risk of extinction.

Research has been conducted on inferior immigrant populations. The authors have investigated the effect of these populations on competitively superior wild species in terms of decline risk, and they report the results.

The use of alternative methods for conservation management where the data are sparse or of low quality and the PVA s have little useful predictive value is discussed. The results suggest that in the absence of any better alternative, the heuristic advantages of PVA, together with its predictive reality, make it by far the best conservation management tool.

The use of alternative methods for conservation management where the data are sparse or of low quality and the PVA s have little useful predictive value is discussed. The results suggest that in the absence of any better alternative, the heuristic advantages of PVA, together with its predictive reality, make it by far the best conservation management tool.

A set of concepts and formulas that can be used in lieu of detailed population viability studies and habitat modeling exercises to determine the protected areas required to provide desirable conservation outcomes for a suite of threatened plant species is outlined. The tools presented in the study provide a fast, transparent and explicit means of assessing the conservation requirements of plants.

The World Conservation Union (IUCN) has defined a set of categories for conservation status and decision rules based on thresholds of various parameters. A specific guideline is proposed to deal with uncertainty, which may be categorized as semantic, measurement error, and natural variability.

Methods for assessing the conservation status of a species for the most part do not allow for underlying uncertainty inherent to the data. For species for which little good data are available, an unreliable estimate of the status of the species results. Threat assessment when there is a range of values can be done within the fuzzy sets framework to broaden evaluation. With two biological variables, use of fuzzy sets together with a point scoring convention brings a range of possible outcomes, not a single one, which would come from the point estimate approach. Different kinds of uncertainty can be used to give a measure of reliability of results. Allowing for uncertainty can change an assessment for a species and can change conservation priorities.