A citizen science based survey method for estimating the density of urban carnivores

Scott, DM, Baker, R, Charman, N, Karlsson, H, Yarnell, RW ORCID logoORCID: https://orcid.org/0000-0001-6584-7374, Mill, AC, Smith, GC and Tolhurst, BA, 2018. A citizen science based survey method for estimating the density of urban carnivores. PLoS ONE, 13 (5): e0197445. ISSN 1932-6203

[thumbnail of 11261_Yarnell.pdf]
Preview
Text
11261_Yarnell.pdf - Published version

Download (1MB) | Preview

Abstract

Globally there are many examples of synanthropic carnivores exploiting growth in urbanisation. As carnivores can come into conflict with humans and are potential vectors of zoonotic disease, assessing densities in suburban areas and identifying factors that influence them are necessary to aid management and mitigation. However, fragmented, privately owned land restricts the use of conventional carnivore surveying techniques in these areas, requiring development of novel methods. We present a method that combines questionnaire distribution to residents with field surveys and GIS, to determine relative density of two urban carnivores in England, Great Britain. We determined the density of: red fox (Vulpes vulpes) social groups in 14, approximately 1km2 suburban areas in 8 different towns and cities; and Eurasian badger (Meles meles) social groups in three suburban areas of one city. Average relative fox group density (FGD) was 3.72 km-2, which was double the estimates for cities with resident foxes in the 1980’s. Density was comparable to an alternative estimate derived from trapping and GPS-tracking, indicating the validity of the method. However, FGD did not correlate with a national dataset based on fox sightings, indicating unreliability of the national data to determine actual densities or to extrapolate a national population estimate. Using species-specific clustering units that reflect social organisation, the method was additionally applied to suburban badgers to derive relative badger group density (BGD) for one city (Brighton, 2.41 km-2). We demonstrate that citizen science approaches can effectively obtain data to assess suburban carnivore density, however publicly derived national data sets need to be locally validated before extrapolations can be undertaken. The method we present for assessing densities of foxes and badgers in British towns and cities is also adaptable to other urban carnivores elsewhere. However this transferability is contingent on species traits meeting particular criteria, and on resident responsiveness.

Item Type: Journal article
Publication Title: PLoS ONE
Creators: Scott, D.M., Baker, R., Charman, N., Karlsson, H., Yarnell, R.W., Mill, A.C., Smith, G.C. and Tolhurst, B.A.
Publisher: Public Library of Science
Date: 2018
Volume: 13
Number: 5
ISSN: 1932-6203
Identifiers:
Number
Type
10.1371/journal.pone.0197445
DOI
Rights: Copyright: © 2018 Scott et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Divisions: Schools > School of Animal, Rural and Environmental Sciences
Record created by: Linda Sullivan
Date Added: 04 Jun 2018 11:07
Last Modified: 04 Jun 2018 11:07
URI: https://irep.ntu.ac.uk/id/eprint/33801

Actions (login required)

Edit View Edit View

Statistics

Views

Views per month over past year

Downloads

Downloads per month over past year