Correlates of rediscovery and the detectability of extinction in mammals

School of Biological Sciences, Goddard Building (8), The University of Queensland, St Lucia, Queensland 4072, Australia.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.05). 09/2010; 278(1708):1090-7. DOI: 10.1098/rspb.2010.1579
Source: PubMed


Extinction is difficult to detect, even in well-known taxa such as mammals. Species with long gaps in their sighting records, which might be considered possibly extinct, are often rediscovered. We used data on rediscovery rates of missing mammals to test whether extinction from different causes is equally detectable and to find which traits affect the probability of rediscovery. We find that species affected by habitat loss were much more likely to be misclassified as extinct or to remain missing than those affected by introduced predators and diseases, or overkill, unless they had very restricted distributions. We conclude that extinctions owing to habitat loss are most difficult to detect; hence, impacts of habitat loss on extinction have probably been overestimated, especially relative to introduced species. It is most likely that the highest rates of rediscovery will come from searching for species that have gone missing during the 20th century and have relatively large ranges threatened by habitat loss, rather than from additional effort focused on charismatic missing species.

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    Herpetological Monographs 12/2014; 28(1):1-23. DOI:10.1655/HERPMONOGRAPHS-D-13-00003 · 1.73 Impact Factor
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    • "The rediscovery of an extinct species may present a variety of regulatory challenges and raise the question of the direction future conservation efforts should take [15]. Although species rediscovery can draw media attention, promote conservation efforts, and encourage research aimed at understanding population declines [9,16], it may also spur unsupported optimism for the survival of the species [12]. Many rediscovered species remain seriously threatened with extinction and could go extinct if concerted efforts are not directed to their conservation [12]. "
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    PLoS ONE 10/2013; 8(10):e78638. DOI:10.1371/journal.pone.0078638 · 3.23 Impact Factor
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    • "A broad climatic niche may also promote resilience to climate change , because it facilitates colo - nization of habitats with changed climate ( Crawford 1997 ) . Broad niches imply physiological tolerance and large geographical ranges ( Fisher & Blomberg 2011a ) , so traits that confer resistance and resilience are not mutually exclusive . Rabinowitz ( 1981 ) and Kattan ( 1992 ) modelled traits likely to determine resistance to environmental change ( geographical range , habitat specificity and local abundance ) and used this to rank the vulnerabil - ity of Columbian birds to extinction . "
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    ABSTRACT: Global climate change is a threat to ecosystems that are rich in biodiversity and endemism, such as the World Heritage-listed subtropical rainforests of central eastern Australia. Possible effects of climate change on the biota of tropical rainforests have been studied, but subtropical rainforests have received less attention. We analysed published data for an assemblage of 38 subtropical rainforest vertebrate species in four taxonomic groups to evaluate their relative vulnerability to climate change. Focusing on endemic and/or threatened species, we considered two aspects of vulnerability, (i) resistance, defined by indicators of rarity (geographic range, habitat specificity and local abundance), and (ii) resilience defined by indicators of a species’ potential to recover (reproductive output, dispersal potential and climatic niche). Our analysis indicates that frogs are most vulnerable to climate change, followed by reptiles, birds, then mammals. Many species in our assemblage are regionally endemic montane rainforest specialists. Monitoring of taxa in regenerating subtropical rainforest showed that many species with high resilience also persist in disturbed habitat, confirming that the resilience model is a good indicator of recolonisation potential. These results will help to prioritise adaptation strategies for species most at risk. We conclude that to safeguard the most vulnerable amphibian, reptile and bird species against climate change, unprotected climatically stable habitats (cool refugia) need to be identified, so that they can be restored and incorporated in the current reserve system, and existing montane subtropical rainforest should be better protected.
    Austral Ecology 04/2013; In Press. DOI:10.1111/j.1442-9993.2012.02437.x · 1.84 Impact Factor
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