Uncertain sightings and declarations of extinction

Uncertain sightings and declarations of extinction

The extinction of a species can be inferred from a record of its sightings. Existing methods for doing so assume that all sightings in the record are valid. Often, however, there are sightings of uncertain validity. To date, uncertain sightings have been treated in an ad hoc way, either excluding them from the record or including them as if they […]

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Modelling plant extinction risk under climate change

Models that couple habitat suitability with demographic processes offer a potentially improved approach for estimating spatial distributional shifts and extinction risk under climate change. Applying such an approach to five species of Australian plants with contrasting demographic traits, the researchers show that: (i) predicted climate-driven changes in range area are sensitive to the underlying habitat model, regardless of whether demographic traits […]

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Assessing species relocations in Australia

Species relocation programs are increasingly performed with the intention of establishing a self-sustaining population of threatened or declining native species. However, the use of experimental quantitative approaches in species relocation programs is still relatively uncommon, despite a number of international studies recommending clear guidelines and standards. This paper evaluates species relocation programs conducted within Australia to assess how programs performed in relation […]

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A Red List of Ecosystems

CEED Workshop (Melbourne, May 2012) The IUCN Red List of Ecosystems was inspired by the success of the IUCN Red List of Threatened Species, which informs governments and society about the current status and trends of species-level biodiversity. The Red List also provides data for the prioritisation of management strategies. While the Red List of Threatened Species is valuable, […]

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The many faces of Marxan

One of the secrets of her success Marxan is a command line interface (CLI) program written in the C programming language. Versions are available for Windows, Mac OSX and Linux. It doesn’t have a graphical user interface (GUI). What does that mean? Basically that, by herself, Marxan is faceless. She accepts inputs as numbered data and she outputs solutions […]

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Marxan out of the ‘box’

More than a sales pitch “Marxan is the most widely used software in the world for supporting the design and implementation of marine and terrestrial reserve systems.” That’s a line many readers would have seen in several stories on Marxan appearing in Decision Point over the years. While it’s demonstrably true, this line is increasingly sounding like a glib […]

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What is this thing called ‘resilience’?

A bluffers guide to resilience thinking The word ‘resilience’ is now common in many vision and mission statements. But ask the people who use these statements what they think it means and you get a range of different answers, most of which relate to how something or someone copes with a shock or a disturbance. Concepts of resilience are […]

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What happens when an economist approaches a threshold?

Ecological thresholds, uncertainty and decision making The concept of thresholds features prominently in ecology and resilience theory. The idea is that if a variable crosses a threshold value, an ecological system can change abruptly and substantially. How this affects decisions made by rational environmental managers can depend greatly on how uncertain they are about the value of the threshold. […]

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Monitoring in the space/time continuum

For effective ecological monitoring, do we preference time or space? Long-term ecological monitoring is universally recognised as critical for understanding ecological systems, how they change over time, and for biodiversity conservation. But long-term ecological monitoring programs often look very different from each other. At one extreme are programs, such as the International Long Term Ecological Research Network (ILTER, see […]

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Bio-perversity in the plantation

Minimizing poor outcomes from carbon plantings Bio-perversity — negative biodiversity and environmental outcomes arising from a narrow policy and management focus on single environmental problems without consideration of the broader ecological context. Like it or not, the carbon economy is coming to town. No-one can predict exactly what it will look like but the bottom line is that one way […]

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Resilience thinking versus decision theory?

No contest There is much discussion about what is often perceived to be alternative paradigms for environmental management – resilience thinking and decision theory. Two recent papers In Trends in Ecology and Evolution (Fischer et al., 2009; Polasky et al. 2011) develop and, in different ways, partially resolve the apparent tension. However, we think there probably wasn’t any tension to […]

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