Increased population density and behavioural flexibility of African clawless otters ( Aonyx capensis ) in specific anthr
- PDF / 554,235 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 3 Downloads / 205 Views
Increased population density and behavioural flexibility of African clawless otters (Aonyx capensis) in specific anthropogenic environments Tshepiso L Majelantle 1 & Andre Ganswindt 1,2,3 & Rowan K Jordaan 1 & David J Slip 4,5 & Robert Harcourt 5 & Trevor McIntyre 1,6 Accepted: 12 October 2020 # Springer Science+Business Media, LLC, part of Springer Nature 2020
Abstract Land transformation for anthropogenic use is the leading cause of species decline globally. However, few species are able to succeed in anthropogenically disturbed environments. African clawless otters (Aonyx capensis) occur in a wide variety of habitats, and thus are good model species to investigate animal adaptation to anthropogenic environments. Therefore, we aimed to estimate and compare population densities, group size, and activity time of African clawless otters occurring in a transformed area, Millstream Farm, and two natural areas, Verloren Vallei Nature Reserve and Cobham Nature Reserve. Camera trap arrays, consisting of between 18, 27 and 24 cameras, were placed on all three sites, recording otter presence for a total of 2439 camera days. Using random encounter models, we estimated that the transformed area had the highest density of African clawless otters (8.2 ± 2.3 km−2), compared to otter densities at Verloren Vallei and Cobham Nature Reserve, South Africa, (natural areas) with estimated densities of 0.7 ± 0.2 km−2 and 2.1 ± 0.6 km−2 respectively. We found a significant difference (p = 0.007) between group sizes in the transformed area (detections = 112; group size range = 1–5) and natural areas (detections = 29; group size range = 1–3). Furthermore, there was a significant difference in otter activity time (p = 0.033, activity overlap = 66.5 ± 8.33%) between Verloren Vallei Nature Reserve and the transformed area at Millstream Farm. This study illustrates how African Clawless otters exhibit behavioural plasticity in order to exploit a resource-rich anthropogenic environment. Keywords Land transformation . Camera traps . Random encounter model . Behavioural plasticity . African clawless otter
Introduction Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11252-020-01068-1) contains supplementary material, which is available to authorized users. * Trevor McIntyre [email protected] 1
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0028, South Africa
2
Endocrine Research Laboratory, Department of Anatomy and Physiology, University of Pretoria, Onderstepoort 0110, South Africa
3
Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
4
Taronga Conservation Society Australia, Bradley’s Head Road, Mosman, NSW 2088, Australia
5
Marine Predator Research Group, Department of Biological Sciences, Macquarie University, North Ryde, NSW 2113, Australia
6
Department of Life and Consumer Sciences, University of South Africa, Roodepoort 1710, South Africa
Good estimates
Data Loading...
