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The spatiotemporal response of species to past global change must be understood for adaptive management and to make useful predictions. Characteristics of past population dynamics are imprinted in genes, yet these molecular 'log books' are just beginning to be used to improve forecasts of biotic responses to climate change. This is despite there now being robust quantitative frameworks to incorporate such information. A tighter integration of genetic data into models of species range dynamics should lead to more robust and validated predictions of the response of demographic and evolutionary processes to large-scale environmental change. The use of these multidisciplinary methods will help conservation scientists to better connect theory to the on-ground design and implementation of effective measures to protect biodiversity. [ABSTRACT FROM AUTHOR]

Ecological niche models (ENMs) are the primary tool used to describe and forecast the potential influence of climate change on biodiversity. However, ENMs do not directly account for important biological and landscape processes likely to affect range dynamics at a variety of spatial scales. Recent advances to link ENMs with population models have focused on the fundamental step of integrating dispersal and metapopulation dynamics into forecasts of species geographic ranges. Here we use a combination of novel analyses and a synthesis of findings from published plant and animal case studies to highlight three seldom recognised, yet important, advantages of linking ENMs with demographic modelling approaches: 1) they provide direct measures of extinction risk in addition to measures of vulnerability based on change in the potential range area or total habitat suitability. 2) They capture life-history traits that permit population density to vary in different ways in response to key spatial drivers, conditioned by the processes of global change. 3) They can be used to explore and rank the cost effectiveness of regional conservation alternatives and demographically oriented management interventions. Given these advantages, we argue that coupled methods should be used preferentially where data permits and when conservation management decisions require intervention, prioritization, or direct estimates of extinction risk. [ABSTRACT FROM AUTHOR]

Abstract: To ensure both long-term persistence and evolutionary potential, the required number of individuals in a population often greatly exceeds the targets proposed by conservation management. We critically review minimum population size requirements for species based on empirical and theoretical estimates made over the past few decades. This literature collectively shows that thousands (not hundreds) of individuals are required for a population to have an acceptable probability of riding-out environmental fluctuation and catastrophic events, and ensuring the continuation of evolutionary processes. The evidence is clear, yet conservation policy does not appear to reflect these findings, with pragmatic concerns on feasibility over-riding biological risk assessment. As such, we argue that conservation biology faces a dilemma akin to those working on the physical basis of climate change, where scientific recommendations on carbon emission reductions are compromised by policy makers. There is no obvious resolution other than a more explicit acceptance of the trade-offs implied when population viability requirements are ignored. We recommend that conservation planners include demographic and genetic thresholds in their assessments, and recognise implicit triage where these are not met. [Copyright &y& Elsevier]

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The article focuses on the issues behind the condition of rare species. Standard bioeconomics claimed that wildlife harvests will stop when the expense of locating individuals of a species surpasses the financial gain, thus protecting that species from overexploitation. However, a group of researchers developed a mathematical model to prove that exploitation of such species can have paradoxical result. Moreover, the author discussed the concept of an Allee effect.

Investigates the predictive accuracy of population viability analysis (PVA) in conservation biology. Use of PVA to predict extinction risks for threatened species and to compare alternative options for their management; Discovery of a closed match between the risk of population decline and observed outcomes; Confirmation of the accuracy of PVA.

The article presents a letter regarding the dangers of media sensationalism in conveying the principles of conservation biology to the masses. According to the authors, media attention is both a blessing and a curse for conservationists. It promotes awareness of the importance of preserving biodiversity, but requires nature programming to be entertaining and eccentric. They argue that "Crocodile Hunter" Steve Irwin misunderstood sustainable use of wildlife, forest fragmentation and how domestic and invasive species can damage biodiversity values. They suggest that Irwin’s perceived martyrdom and the subsequent slaughter of stingrays is evidence that his fans did not fully embrace conservation issues.

Highlights: [•] Genetic factors remain inadequately addressed in conservation management. [•] Effective population size (Ne )=50 does not prevent inbreeding depression. [•] Ne ⩾100 is required to limit inbreeding depression to 10% over 5 generations. [•] Ne =500 is too low for retaining evolutionary potential; Ne ⩾1000 is required. [•] IUCN Red List Criterion C thresholds for population size require doubling. [Copyright &y& Elsevier]

We present the first meta-analysis of a key measure in conservation biology: minimum viable population (MVP) size. Our analysis is based on studies published since the early 1970s, and covers 141 sources and 212 species (after filtering 529 sources and 2202 species). By implementing a unique standardization procedure to make reported MVPs comparable, we were able to derive a cross-species frequency distribution of MVP with a median of 4169 individuals (95% CI=3577–5129). This standardized database provides a reference set of MVPs from which conservation practitioners can generalize the range expected for particular species (or surrogate taxa) of concern when demographic information is lacking. We provide a synthesis of MVP-related research over the past 30 years, and test for ‘rules of thumb’ relating MVP to extinction vulnerability using well-known threat correlates such as body mass and range decline. We find little support for any plausible ecological and life history predictors of MVP, even though correlates explain >50% of the variation in IUCN threat status. We conclude that a species’ or population’s MVP is context-specific, and there are no simple short-cuts to its derivation. However, our findings are consistent with biological theory and MVPs derived from abundance time series in that the MVP for most species will exceed a few thousand individuals. [Copyright &y& Elsevier]