Crocuta Crocuta)
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applyparastyle "fig//caption/p[1]" parastyle "FigCapt" applyparastyle "fig" parastyle "Figure" Journal of Mammalogy, 100(6):1941–1953, 2019 DOI:10.1093/jmammal/gyz135 Published online September 18, 2019 Pastoralist activities affect the movement patterns of a large African carnivore, the spotted hyena (Crocuta crocuta) David S. Green* and Kay E. Holekamp Department of Integrative Biology, Michigan State University, East Lansing, MI 48823 (DSG, KEH) Program in Ecology, Evolutionary Biology, and Behavior, Michigan State University, East Lansing, MI 48823 (DSG, KEH) Downloaded from https://academic.oup.com/jmammal/article/100/6/1941/5571540 by guest on 25 September 2021 Present address of DSG: Institute for Natural Resources, Oregon State University, Corvallis, OR 97331 * Correspondent: [email protected] Populations of large carnivores are declining in many parts of the world due to anthropogenic activity. Some species of large carnivores, however, are able to coexist with people by altering their behavior. Altered behaviors may be challenging to identify in large carnivores because these animals are typically cryptic, nocturnal, live at low densities, and because changes in their behavior may be subtle or emerge slowly over many years. We studied the effects of livestock presence on the movements of one large carnivore, the spotted hyena (Crocuta crocuta). We fit 22 adult female spotted hyenas with GPS collars to quantify their movements in areas with and without livestock or herders present, in and around a protected area in southwestern Kenya. We investigated anthropogenic, social, and ecological effects on the speed of movement, distances traveled, long-distance movements, and extraterritorial excursions by spotted hyenas. Hyenas living primarily within the protected area, but in the presence of livestock and herders, moved faster, traveled over longer distances, and were more likely to be within their territories than did conspecifics living in areas without livestock and herders. Hyenas of low social rank were more likely than hyenas of high social rank to engage in long-distance travel events, and these were more likely to occur when prey were scarce. The movement patterns of this large African carnivore indicate a flexibility that may allow them to persist in landscapes that are becoming increasingly defined by people. Key words: anthropogenic disturbance, Crocuta crocuta, East Africa, GPS collars, Mara-Serengeti ecosystem, pastoralism, protected areas Large carnivores often occupy apex trophic positions in their for real or perceived threats to livestock in North America and natural habitats, and they may limit populations of both sym- Europe (e.g., wolves Canis lupus—Liberg et al. 2012), and patric prey and other predators. However, populations of large hunted for sport in Africa (e.g., lions Panthera leo—Packer carnivores have been declining worldwide (Ripple et al. 2014). et al. 2009, 2010). This persecution has extirpated large carni- The reduction or complete extirpation of large carnivores can vore species from many ecosystems (Ripple et al. 2014). Other have ecosystem-wide consequences due to the removal of the effects of people on large carnivore populations may be indi- top-down control they exert over species at lower trophic levels rect, and these can include habitat loss and reduced prey avail- (Miller et al. 2001; Schmitz et al. 2010; Ripple et al. 2014). ability due to overharvesting (Ripple et al. 2014). The indirect Declining numbers of large carnivores can effect changes in bi- effects of humans on large carnivores have been harder to elu- odiversity (Estes et al. 2011) and disease prevalence (Levi et al. cidate than direct effects because they may elicit only subtle 2012), and often have negative economic consequences at both changes in the carnivores themselves, and because they may local and national levels (Taylor et al. 2016). take years to manifest. The negative effects of people on large carnivores are a factor Protected areas can help prevent conflicts between humans contributing to their declining numbers. For example, large car- and carnivores (Packer et al. 2013; Bauer et al. 2015), and most nivores are poached for their body parts in Asia (e.g., tigers populations of large carnivores currently reside within or ad- Panthera tigris—Dinerstein et al. 2007), killed in retaliation jacent to protected areas. However, edge effects associated © 2019 American Society of Mammalogists, www.mammalogy.org 1941 1942 JOURNAL OF MAMMALOGY with nearby human populations, and human pressures inside of livestock elicits changes in the movement patterns of spotted the protected areas, have cast considerable doubt on the effi- hyenas in areas where they are being disturbed by people and cacy of protected areas as sanctuaries for carnivore conserva- livestock, 2) variation in hyena movements due to livestock is tion (Woodroffe and Ginsberg 1998; Wittemyer et al. 2008; also affected by social rank, and 3) certain ecological condi- Loveridge et al. 2017). For example, anthropogenic disturbance tions (e.g., rainfall, temperature, moonlight, prey availability) within protected areas can affect carnivore community struc- affect the movements of spotted hyenas, regardless of their so- ture (Baker and Leberg 2018; Farr et al. 2019) and influence cial rank or the presence of livestock. We also inquired whether their use of space (Olson et al. 2018; Ladle et al. 2019). In some the presence of livestock within the territorial boundaries of a areas of the world, conflict between carnivores and livestock spotted hyena clan increases the probability that hyenas spend or the people protecting them is a major cause of the decline time outside those same boundaries. Downloaded from https://academic.oup.com/jmammal/article/100/6/1941/5571540 by guest on 25 September 2021 in carnivore numbers (Woodroffe and Ginsberg 1998; Ripple et al. 2014), even within protected areas (Green et al. 2018). Aside from retaliatory killings, the mere presence of livestock Materials and Methods within protected areas can affect carnivore ecology and be- Study site.—From April 2012 through November 2014, we havior (Soofi et al. 2018; Broekhuis et al. 2019). Thus, under- studied the movement patterns of spotted hyenas within and standing how the activity of pastoralists may be influencing the around the Masai Mara National Reserve (henceforth, “the behaviors of large carnivores represents an important area of Reserve”) in southwestern Kenya (Fig. 1). The Reserve is cov- research due to increasing numbers of both humans and live- ered primarily with open grassland interspersed with riparian stock, particularly in developing nations. habitat along seasonal watercourses. The Reserve has histori- Behavior is the first line of defense for many species to cope cally supported many resident herbivore and carnivore species with changing environments (Sih 2013; Wong and Candolin year-round, and it is also visited seasonally by migrating herbi- 2015; Sih et al. 2016), and large carnivores often modify their vores from the Serengeti National Park to the south (Bell 1971; behaviors to mitigate the negative effects of people. It has been Sinclair and Norton-Griffiths 1979), and the Loita Plains to the hypothesized that the slow life histories, large body sizes, and northeast (Stelfox et al. 1986). The only permanent river in the complex habitat requirements of large carnivores might pre- Reserve, the Mara River, also serves as the boundary between vent them from finding ways to coexist with humans (Cardillo two different management agencies operating on its eastern 2005). In contrast to predictions of this hypothesis, empirical and western sides, respectively (Fig. 1). The eastern side of the work has shown that some large carnivores living in human- Reserve is managed by the Narok County Government. Within dominated landscapes can alter their behaviors in subtle ways the eastern side of the Reserve, the Talek region, in particular, to coexist with people. Some species shift their activity pat- is an area near the border that in recent decades has been sub- terns to become more nocturnal (Gaynor et al. 2018), increase jected to an exponential increase in the number of livestock their vigilance (Pangle and Holekamp 2010), modify how they present inside the Reserve (Boydston et al. 2003a; Kolowski navigate landscapes occupied by humans (Oriol-Cotterill et al. and Holekamp 2009; Green et al. 2018, 2019b). Formation of 2015), and change their space use to avoid areas of human ac- several private conservancies north of the Reserve (Fig. 1) has tivity altogether (Van Dyke et al. 1986; Schuette et al. 2013). created an island of land, called Talek town and environs, occu- Here, we used GPS collar technology to examine the ways in pied by several thousand Masai pastoralists and their livestock. which the movements of wild spotted hyenas (Crocuta crocuta) Herders from Talek communities accompanying their livestock were affected by livestock presence, while also accounting for inside the Reserve are armed with weapons (e.g., clubs, spears), other socio-ecological factors that might affect hyena move- and conflicts between herders and hyenas stemming from live- ments. Spotted hyenas are gregarious large carnivores that ex- stock depredation now represent the greatest source of mor- hibit remarkable plasticity in many aspects of their behavior tality for hyenas on the eastern side of the Reserve (Pangle and (Holekamp and Dloniak 2010). Spotted hyenas can cope