Determining the diet of an African mesocarnivore, the caracal: scat or GPS cluster analysis? Authors: Corlé Jansen, Alison J. Leslie, Bogdan Cristescu, Kristine J. Teichman, and Quinton Martins Source: Wildlife Biology, 2019(1) Published By: Nordic Board for Wildlife Research URL: https://doi.org/10.2981/wlb.00579 BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Complete website, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/terms-o-use. Usage of BioOne Complete content is strictly limited to personal, educational, and non - commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. Downloaded From: https://bioone.org/journals/Wildlife-Biology on 31 Oct 2019 Terms of Use: https://bioone.org/terms-of-use Wildlife Biology 2019: wlb.00579 doi: 10.2981/wlb.00579 © 2019 The Authors. This is an Open Access article Subject Editor: Al Glen. Editor-in-Chief: Ilse Storch. Accepted 29 August 2019 Determining the diet of an African mesocarnivore, the caracal: scat or GPS cluster analysis? Corlé Jansen, Alison J. Leslie, Bogdan Cristescu, Kristine J. Teichman and Quinton Martins C. Jansen, (https://orcid.org/0000-0002-8441-9639) ✉ ([email protected]) and A. J. Leslie, Dept of Conservation Ecology and Entomology, Stellenbosch Univ., Private Bag X1, 7602 Matieland, South Africa. – B. Cristescu and K. J. Teichman, The Cape Leopard Trust, Tokai, Cape Town, South Africa. BC also at: Inst. for Communities and Wildlife in Africa (iCWild), Dept of Biological Sciences, Univ. of Cape Town, Rondebosch, Cape Town, South Africa. KJT also at: Dept of Biology, Univ. of British Columbia, Kelowna, Canada. – Q. Martins, Audubon Canyon Ranch, Glen Ellen, CA, USA. The caracal Caracal caracal is the largest of Africa’s small felids (<20 kg). Across much of Africa, particularly where larger predators have been extirpated, caracal are one of the main carnivores contributing to livestock predation. Caracal dietary studies are outdated, typically have small sample sizes and have mainly relied on scat analysis. We used a combination of scat analysis (n = 250 scats) and GPS cluster visitation (n = 458 clusters visited; n = 91 clusters with feeding events) to estimate caracal diet in South Africa’s Succulent Karoo, a global biodiversity hotspot. Based on both methods, rock hyrax Procavia capensis was the caracal’s main prey. Small mammals accounted for 25.3% of total biomass consumed by caracal using scat analysis, however, were absent based on GPS cluster investigations. Domestic sheep Ovis aries biomass consumed was much higher (59.5%) when inferred from GPS cluster visitation than from scats (5%). Wild medium-to-large mam- malian prey had little variation between the two methods. GPS telemetry did not enable detection of small prey (<1 kg) and possibly over-represented large prey items, including livestock. Scat analysis provided a broader representation of cara- cal diet, but scat investigations could have underestimated larger prey since caracals ingest only small amounts of hair from large-bodied animals. We recommend a combination of GPS cluster visitation and scat analysis to determine the diet of caracal and other mesocarnivores across a range of prey sizes. Keywords: Caracal caracal, feeding ecology, mesocarnivore, predator–prey interactions, prey composition, Succulent Karoo, trophic spectrum The caracal Caracal caracal is a solitary felid and the largest ses (Iverson et al. 2004, Thompson et al. 2005). However, of Africa’s smaller felids (<20 kg), with males weighing up these methods typically cannot differentiate between species– to 15 kg and females up to 12 kg (Skinner and Chimimba specific prey items for complex multi-prey systems 2005). Previous caracal diet studies mostly utilised the inva- (Hardy et al. 2010). sive method of stomach contents analysis of dead caracal, Global positioning system (GPS) technology has or alternatively non-invasive scat analysis (Grobler 1981, advanced carnivore research substantially (Cagnacci et al. Stuart 1982, Palmer and Fairall 1988, Avenant and Nel 1997, 2010) with increased accuracy of kill site identification Avenant and Nel 2002, Braczkowski et al. 2012). Scat analysis (Bacon et al. 2011, Martins et al. 2011), as well as provid- can overestimate the importance of smaller prey items, such ing valuable insight into other aspects of carnivore ecology as rodents and invertebrates, in a predator’s diet (Klare et al. including movement (Martins and Harris 2013, Odden et al. 2011); however, data analysis methods have been developed 2014), resting (Cristescu et al. 2013) and habitat selection to decrease such biases (Ciucci et al. 1996, Marucco et al. (Cristescu et al. 2014, Fattebert et al. 2015). The use of 2008, Klare et al. 2011). Other methods used in dietary GPS cluster visitation as a method to estimate carnivore investigations include stable isotope and fatty acid analy- diet has been reported to over-represent larger prey items (Pitman et al. 2012, Tambling et al. 2012, Clark et al. 2014). Svoboda et al. (2013) is one of the few studies wherein GPS This work is licensed under the terms of a Creative Commons Attribution 4.0 International License (CC-BY) < http:// radio-collars were used to determine and visit kill sites of creativecommons.org/licenses/by/4.0/ >. The license permits a mesocarnivore, the bobcat Lynx rufus. This study, how- use, distribution and reproduction in any medium, provided the ever, only focused on locating white-tailed deer Odocoileus original work is properly cited. virginianus kill sites. Studies in Africa utilising GPS clusters 1 Downloaded From: https://bioone.org/journals/Wildlife-Biology on 31 Oct 2019 Terms of Use: https://bioone.org/terms-of-use to determine carnivore diet have been restricted to large carni- Material and methods vores, such as leopards Panthera pardus and lions Panthera leo (Tambling et al. 2010, Martins et al. 2011, Pitman et al. Study area 2012). To our knowledge, mesocarnivore diet composition has not been reported using a combination of GPS cluster The 810 km² study area forms part of the Namaqualand visitation and scat analyses outside of North America. District, Northern Cape, South Africa (Fig. 1). The area Caracal are reported to be one of the main mesocarni- falls within the Succulent Karoo Biome, one of only two vores responsible for livestock predation in South Africa semi-arid biodiversity hotspots in the world (Mittermeier (Avenant and Du Plessis 2008, Van Niekerk 2010). The et al. 2005). Namaqualand makes up approximately a need to understand their feeding ecology has been empha- quarter of the Succulent Karoo and boasts 3500 floral spe- sized in various past studies that have highlighted their cies in 135 families and 724 genera, of which 25% are potential for extensive damage to livestock (Avenant and endemic (Driver et al. 2003, Desmet 2007). Namaqualand Du Plessis 2008, Bergman et al. 2013, Du Plessis et al. is classified as a winter rainfall region (Cowling et al. 2015). Yet, management of caracal is often conducted 1999), with a mean annual precipitation of 160 mm. based on assumptions and traditional knowledge, with little The study area includes the eastern section of Namaqua scientific evidence contributing to management decisions National Park (30°16′62.7″S, 017°79′61.9″E) and sur- (Kerley et al. 2017). rounding commercial farms with free-ranging small-stock The main objective of this study was to compare caracal (sheep and goats) to the north, east and south of the diet estimation using scat analysis and GPS cluster visitation. national park. In addition to hosting naturally occurring We provide the first documentation on the comparative use small antelope species such as common duiker Sylvicapra of these two methods applied to a mesocarnivore species grimmia, klipspringer Oreotragus oreotragus and steenbok outside North America and hypothesize that the methods Raphicerus campestris, the national park also re-introduced of sampling (scat versus field investigation of GPS location springbok Antidorcas marsupialis, gemsbok Oryx gazelle and clusters) will influence the outcome of caracal diet estima- red hartebeest Alcelaphus buselaphus. Black-backed jackal tion. We hypothesize that scat analysis will reveal a greater Canis mesomelas are the caracal’s primary competitor but occurrence and biomass of small prey items than GPS clus- smaller carnivores such as Cape fox Vulpes chama, small- ter investigations, which will show diet to be dominated by spotted genet Genetta genetta and Cape grey mongoose large prey items. Based on the results of the methodological Galerella pulverulenta, as well as raptors may scavenge on comparison, we formulate suggestions for future studies on caracal kills. The leopard Panthera pardus, an apex preda- mesocarnivore diet. tor, also occurs within the study area. Figure 1. A map of South Africa (insert) showing the location of the study area in the Northern Cape. Locations of caracal Caracal caracal scats collected are indicated as a triangle and caracal clusters where prey remains were found using GPS cluster analysis are indicated as stars. 2 Downloaded From: https://bioone.org/journals/Wildlife-Biology on 31 Oct 2019 Terms of Use: https://bioone.org/terms-of-use Caracal capture and immobilization Prey species and when possible, prey sex and age (adult; sub-adult; and young-of-year [YoY]) were determined. Age Eight male caracal were captured from March 2014–April assignment was done based on tooth wear (incisors and pre- 2015 using cage traps and padded foothold traps. Cara- molars) and gum recession line (Schroeder and Robb 2005).