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Inferring extinctions from sighting records of variable reliability

Lee, Tamsin E., McCarthy, Michael A., Wintle, Brendan A., Bode, Michael, Roberts, David L., Burgman, Mark A. (2013) Inferring extinctions from sighting records of variable reliability. Journal of Applied Ecology, 51 (1). pp. 251-258. ISSN 0021-8901. (doi:10.1111/1365-2664.12144) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)

The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided. (Contact us about this Publication)
Official URL
http://dx.doi.org/10.1111/1365-2664.12144

Abstract

A range of mathematical models has been developed to infer whether a species is extinct based on a sighting record. Although observations have variable reliability, current methods for detecting extinction do not differentiate observation qualities. A more suitable approach would consider certain and uncertain sightings throughout the sighting period. We consider a small population system, meaning we assume sighting rates are constant and the population is not declining. Based on such an assumption, we develop a Bayesian method that assumes that certain and uncertain sightings occur independently and at uniform rates. These two types of sightings are connected by a common extinction date. Several rates of false sightings can be calculated to differentiate between observation types. Prior rates of false and true sightings, as well as a prior probability that the species is extant, are included. The model is implemented in OpenBugs, which uses Markov chain Monte Carlo (MCMC). Based on records of variable reliability, we estimate the probability that the following species are extinct: Caribbean seal Monachus tropicalis, grey, black-footed ferret Mustela nigripes, Audubon & Bachman, greater stick-nest rat Leporillus conditor, Sturt, and lesser stick-nest rat Leporillus apicalis, Gould. As further examples, Birdlife International provided the sighting records for the Alaotra grebe Tachybaptus rufolavatus, Delacour, Jamaica petrel Pterodroma caribbaea, Carte, and Pohnpei mountain starling Aplonis pelzelni, Finsch, with prior probabilities for extinction. The results are compared with existing methods, which ignore uncertain sightings. We find that including uncertain sightings can considerably change the probability that the species is extant, in either direction. However, in our examples, including the quality of the uncertain sighting made little difference. When we ignore uncertain sightings, our results agree with existing methods, especially when the last sighting was near the end of the sighting period. Synthesis and applications. Estimating the probability that a species is extinct based on sighting records is important when determining conservation priorities and allocating available resources into management activities. Having a model that allows for certain and uncertain observations throughout the sighting period better accommodates the realities of sighting quality, providing a more reliable basis for decision-making. © 2013 The Authors. Journal of Applied Ecology © 2013 British Ecological Society.

Item Type: Article
DOI/Identification number: 10.1111/1365-2664.12144
Additional information: Unmapped bibliographic data: AD - School of Botany, University of Melbourne, Parkville, 3010, Australia [Field not mapped to EPrints] AD - Durrell Institute of Conservation and Ecology, School of Anthropology and Conservation, University of Kent, Kent, CT2 7NR, United Kingdom [Field not mapped to EPrints] JA - J. Appl. Ecol. [Field not mapped to EPrints]
Uncontrolled keywords: Anomalous reports, Bayes factor, Extirpation, Species persistence, Uncertainty
Subjects: Q Science
Q Science > QH Natural history > QH75 Conservation (Biology)
Divisions: Faculties > Social Sciences > School of Anthropology and Conservation
Faculties > Social Sciences > School of Anthropology and Conservation > DICE (Durrell Institute of Conservation and Ecology)
Depositing User: David Roberts
Date Deposited: 20 Feb 2014 14:22 UTC
Last Modified: 29 May 2019 11:53 UTC
Resource URI: https://kar.kent.ac.uk/id/eprint/38392 (The current URI for this page, for reference purposes)
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