Making inference from wildlife collision data: inferring predator absence from prey strikes
- Published
- Accepted
- Subject Areas
- Conservation Biology, Ecology, Mathematical Biology, Statistics
- Keywords
- Distribution, extinction, incursion, roadkill, wildlife collision, runway strike, numerical response, wildlife strike, Vulpes vulpes
- Copyright
- © 2016 Caley et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2016. Making inference from wildlife collision data: inferring predator absence from prey strikes. PeerJ Preprints 4:e2572v1 https://doi.org/10.7287/peerj.preprints.2572v1
Abstract
Wildlife collision data are ubiquitous, though challenging for making ecological inference due to typically irreducible uncertainty relating to the sampling process. We illustrate a new approach that is useful for generating inference from predator data arising from wildlife collisions. By simply conditioning on a second prey species sampled via the same collision process, and by using a biologically realistic numerical response functions, we can produce a coherent numerical response relationship between predator and prey. This relationship can then be used to make inference on the population size of the predator species, including the probability of extinction. The statistical conditioning enables us to account for unmeasured variation in factors influencing the runway strike incidence for individual airports and to enable valid comparisons. A practical application of the approach for testing hypotheses about the distribution and abundance of a predator species is illustrated using the hypothesized red fox incursion into Tasmania, Australia. We estimate that conditional on the numerical response between fox and lagomorph runway strikes on mainland Australia, the predictive probability of observing no runway strikes of foxes in Tasmania after observing 15 lagomorph strikes is 0.001. We conclude there is enough evidence to safely reject the null hypothesis that there is a widespread red fox population in Tasmania at a population density consistent with prey availability. The method is novel and has potential wider application.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Summarized runway strike data as analysed
Number of runway strikes for red foxes and lagomorphs (European hares & rabbits) recorded in Australian states and territories over the period 2002--2014. Source: Australian Traffic Safety Bureau.
R Code
R Code to run analyses. Will require OpenBUGS.