
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/317136591 Carnivore distributions in Botswana are shaped by resource availability and intraguild species Article in Journal of Zoology · May 2017 DOI: 10.1111/jzo.12470 CITATIONS READS 41 778 5 authors, including: Lindsey Rich J. Weldon Mcnutt California Department of Fish and Wildlife 132 PUBLICATIONS 3,502 CITATIONS 35 PUBLICATIONS 757 CITATIONS SEE PROFILE SEE PROFILE Marcella J. Kelly Virginia Polytechnic Institute and State University 207 PUBLICATIONS 5,184 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: African wild dog population monitoring in Northern Botswana View project Master's Research View project All content following this page was uploaded by Lindsey Rich on 04 October 2017. The user has requested enhancement of the downloaded file. Journal of Zoology. Print ISSN 0952-8369 Carnivore distributions in Botswana are shaped by resource availability and intraguild species L. N. Rich1, D. A. W. Miller2, H. S. Robinson3,4, J. W. McNutt5 & M. J. Kelly1 1 Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA, USA 2 Department of Ecosystem Science and Management, Penn State, University Park, PA, USA 3 College of Forestry and Conservation, University of Montana, Missoula, MT, USA 4 Panthera, New York, NY, USA 5 Botswana Predator Conservation Trust, Maun, Botswana Keywords Abstract camera trap; carnivore; community dynamics; intraguild species; occupancy modeling; seasonal The composition of ecological communities is shaped by the interplay between distributions. interspecific interactions and species’ habitat and food requirements. The influence of interspecific interactions is particularly widespread within carnivore guilds, Correspondence where species must balance the trade-off between resource acquisition and poten- Lindsey N. Rich, Department of Fish and Wildlife tially costly encounters with intraguild competitors/predators. We tested whether Conservation, Virginia Tech, 318 Cheatham Hall, intraguild species activity or resource availability had a stronger influence on the Blacksburg, VA 24061-0321, USA. seasonal distributions of 10 carnivore species in northern Botswana. We deployed Email: [email protected] 132 camera stations across a 330 km2 area during the 2014 dry season and 2015 wet season. For each species and season, we developed occupancy models based Editor: Matthew Hayward on resource availability (i.e. prey, vegetation and water) and on intraguild species (i.e. photographic detection rates of intraguild competitors and predators). We then Received 16 June 2016; revised 29 March 2017; used k-fold cross-validation to assess the relative predictive ability of each model. accepted 4 April 2017 Carnivore distributions were generally negatively associated with dense vegetation and contrary to expectations, positively associated with the detection rate of intra- doi:10.1111/jzo.12470 guild species. This suggests competitor/predator avoidance did not play a large role in influencing carnivore distributions in northern Botswana, a result that differs from other systems, and might be attributed to differences in habitat, carnivore den- sities, and prey availability. The predictive ability of our resource availability vs. intraguild species models differed between seasons and among species. Leopard distributions, for example, were best predicted by resource availability during the dry season and by the activity of intraguild species in the wet season. The majority of seasonal distributions were best predicted by intraguild species activity or a combination of both resource availability and intraguild species activity. As envi- ronments continually change, studies similar to ours are pertinent as they can be used to monitor distributions of wildlife communities and to better understand the relative importance of the diversity of ecological processes impacting wildlife com- munities. Introduction Such information is especially pertinent for mammalian carni- vores as they are wide ranging, sensitive to environmental and Carnivore populations have declined globally due to increasing land use changes, and generally exist at low densities, making human populations, widespread habitat loss, and declining prey them particularly vulnerable to local extinctions (Woodroffe & populations (Ripple et al., 2014; Bauer et al., 2015). African Ginsberg, 1998; Bauer et al., 2015). wild dogs (Lycaon pictus), tigers (Panthera tigris), and lions The composition of carnivore communities is shaped by the (Panthera leo), for example, have each disappeared from interplay between competitive interactions, and species’ habitat >80% of their historical range (Ripple et al., 2014; Bauer and food requirements (Rosenzweig, 1966; Holt, 1984). Com- et al., 2015). As the extent and quality of wildlife habitat petitive interactions are particularly widespread within the car- erodes, information on the distributions of remaining carnivore nivore community, influencing individual behavior, population populations is needed to facilitate informed conservation dynamics, and community structure (Rosenzweig, 1966; Palo- actions aimed at mitigating declines (Pettorelli et al., 2010). mares & Caro, 1999; Caro & Stoner, 2003). Typically, Journal of Zoology (2017) – ª 2017 The Zoological Society of London 1 Carnivore distributions in Botswana L. N. Rich et al. competition increases as carnivore species become more similar availability, whereas the distributions of meso-carnivores would in habitat selection, diet, activity pattern, and body size be influenced by both resource availability and the activity of (Rosenzweig, 1966). Interspecific killing (i.e. killing with or intraguild species (Palomares & Caro, 1999; Heithaus, 2001). without consumption), alternatively, is more likely among car- By evaluating the relative importance of the diversity of eco- nivore species with body sizes that differ by a factor of 2–5.4 logical processes impacting carnivore communities, our and with overlapping diets (Donadio & Buskirk, 2006). The research aims to inform the conservation of these wildlife pop- potential for intraguild interactions can result in spatial and ulations in sub-Saharan Africa. temporal niche partitioning among species, with subordinate species often changing their habitat use to less optimal areas in Materials and methods an effort to minimize encounters with dominant species (Creel & Creel, 1996; Durant, 1998). This can result in top predators Study area matching the distributions of their prey, while subordinate predators balance the trade-off between resource acquisition Our study was carried out in Ngamiland District of northern and risk of aggression and kleptoparasitism from larger preda- Botswana. The dominant land covers included floodplains, tors (Palomares & Caro, 1999; Heithaus, 2001). In East Africa, grasslands, and mopane shrub (Colophospermum mopane) and for example, cheetahs (Acinonyx jubatus) and wild dogs, both woodlands. Our study site encompassed the eastern section of subordinate competitors, occurred in areas with lower prey Moremi Game Reserve and parts of wildlife management areas densities than areas frequented by lions and spotted hyenas NG33/34 (Fig. 1). Wildlife was fully protected within Moremi (Crocuta crocuta), the dominant competitors (Creel & Creel, Game Reserve and partially protected within the wildlife man- 1996; Durant, 1998). agement areas. Both areas were used for photographic tourism When modeling intraguild interactions and community (i.e. no hunting or livestock grazing). The region has two dis- dynamics, it is also vital to account for species’ decisions tinct seasons, dry and wet, with rain (~300–600 mm/year) fall- regarding habitat use, as habitat selection plays an important ing almost exclusively during the wet season, which generally role in determining population dynamics and community struc- lasts from November to April. ture (Brown, Laundre & Gurung, 1999; Heithaus, 2001). Prey density, for example, has been found to be a fundamental dri- Camera trap survey ver of carnivore densities and distributions (Carbone & Gittle- man, 2002) as has water availability, with carnivore occupancy We deployed camera stations at 132 locations across a 330 km2 often increasing close to permanent water sources (Pettorelli area between August and November 2014 (dry season) and again et al., 2010; Schuette et al., 2013). Vegetation cover and pro- between February and May 2015 (wet season). Each camera sta- ductivity may also influence carnivore distributions, often due tion included two opposing cameras, offset by 0.5–1 m. The to their relationships with prey abundance (Pettorelli et al., majority of cameras were Panthera v4 incandescent-flash camera 2005). traps (0.18 s trigger speed) but we also used several Bushnell The mammalian carnivore community in northern Botswana TrophyCam infra-red camera traps (0.3 s trigger speed). To keep is one of the most diverse assemblages of carnivores in Africa detection rates comparable among stations, we ensured every (Caro & Stoner, 2003). The strength and frequency of interac- camera station included at least one Panthera camera trap. We tions within this carnivore guild likely varies based on resource mounted cameras on trees and if no trees were available, on availability, the respective species’ resource requirements, and metal fence posts hammered into the ground. We secured cam- their rank
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