The Ecological Role of Native and Introduced Species in the Diet of The
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The ecological role of native and introduced species in the diet of the puma Puma concolor in southern Patagonia J uan Ignacio Z ano´ nMartı´ nez,Alejandro T ravaini,Sonia Z apata ´ D iego P rocopio and M iguel Angel S antillA´ n Abstract There is evidence for the ecological extinction of Introduction the native prey of the puma Puma concolor in north- western Argentine Patagonia. In this study we examine he puma Puma concolor is a generalist predator whether this is also the case in southern Patagonia. From Tthroughout its wide distribution in the Western Hemi- 2009 2004 to 2007 we examined the puma’s diet in three sphere (Wilson & Mittermeier, ). Its diet can be protected areas and two sheep ranches in Santa Cruz affected by the abundance and vulnerability of its prey, province. A total of 282 puma scats were analysed. In two habitat characteristics, competition with other carnivores 1983 1990 of the protected areas and in the ranches 60–74% of the (Currier, ; Iriarte et al., b), fluctuations in its native 2000 2003 puma’s diet was native prey. Prey species were primarily prey populations (Novaro et al., ; Polisar et al., ) 2001 guanaco Lama guanicoe, followed by Patagonian mara and anthropogenic factors (Fuller & Sievert, ). The Dolichotis patagonum, lesser rhea Pterocnemia pennata varied diet of the puma across its range reflects the diverse 2002 pennata, Patagonian pichi Zaedyus pichiy and Magellanic habitats it inhabits (Sunquist & Sunquist, ). The puma penguin Spheniscus magellanicus. In the third protected can satisfy its food requirements by predating on either area the main prey was the European hare Lepus euro- native or introduced wild and domestic species (Ackerman 1984 1994 1996 paeus. Our results show a clear difference in the diet of the et al., ; Ockenfels, ; Wehausen, ; Franklin et al., 1999 2000 2009 puma in southern compared to north-western Patagonia. ; Novaro et al., ; Donadio et al., ; Foster 2010 1 150 Large native herbivores (i.e. guanaco and lesser rhea) et al., ) of a wide variety of sizes (, – kg; Iriarte 1990 maintain their role as the main prey species for the puma et al., b). Although categorized as Least Concern on the in southern Patagonia. We suggest, therefore, that IUCN Red List because it is a widespread species, the puma native prey could be restored to those areas of Argentine is considered to be declining and its conservation presents 2008 Patagonia, such as the north-west, where they are currently numerous challenges (Caso et al. ). ecologically extinct. Facilitating native species recovery In North America the puma’s diet formerly comprised 2005 and/or restoration and applying more rigorous controls large prey, especially ungulates (Beck et al., ). For to prevent the introduction of potential alien prey species example, mule deer Odocoileus hemionus, pronghorn of the puma, both within and outside protected areas, Antilocapra americana and bighorn sheep Ovis canadensis needs to be evaluated as a regional strategy. are important components of the puma’s diet in the states of Utah, Arizona and California, USA, respectively Keywords Argentina, diet, ecological extinction, Patagonia, (Ackerman et al., 1984; Ockenfels, 1994; Wehausen, 1996). predation, Puma concolor In the tropical areas of Central and South America the puma’s prey includes a wide range of species and sizes, from ungulates to small mammals such as deer, and marsupials and small and large rodents (Rabinowitz & JUAN IGNACIO ZANO´ N MARTI´NEZ* (Corresponding author) and SONIA Nottingham, 1986; Iriarte et al., 1990b; Scognamillo et al., ZAPATA Centro de Investigaciones de Puerto Deseado, Universidad Nacional 2003 2010 de la Patagonia Austral, C.C. 238, Avenida Prefectura Naval S/N, 9050 Puerto ; Foster et al., ). In Chilean Patagonia the diet of Deseado, Santa Cruz, Argentina. E-mail [email protected] the puma is dominated by large-bodied native prey such as ALEJANDRO TRAVAINI and DIEGO PROCOPIO Centro de Investigaciones de the guanaco Lama guanicoe and pudu Pudu pudu but Puerto Deseado, Universidad Nacional de la Patagonia Austral, Consejo pumas also prey on introduced species such as domestic Nacional de Investigaciones Cientı´ficas y Te´cnicas, Puerto Deseado, Santa Cruz, Argentina sheep Ovis aries and European hare Lepus europaeus 1984 ´˜ 1986 1990 MIGUEL A´ NGEL SANTILLA´ N Centro para el Estudio y Conservacio´n de las (Wilson, ;Yanez et al., ; Iriarte et al., b; Aves Rapaces en Argentina, Universidad Nacional de La Pampa, Santa Rosa, Franklin et al., 1999; Rau & Jime´nez, 2002). La Pampa, Argentina There are few studies of the puma’s diet in Argentine *Also at: Consejo Nacional de Investigaciones Cientı´ficas y Te´cnicas, Centro Patagonia. Studies during 1984–1997 at Lihuel Calel Na- para el Estudio y Conservacio´n de las Aves Rapaces en Argentina, Universidad Nacional de La Pampa, Santa Rosa, La Pampa, Argentina tional Park in southern La Pampa province showed that Received 21 July 2010. Revision requested 7 October 2010. puma diet comprised mainly plains vizcacha Lagostomus Accepted 9 December 2010. maximus, a rodent weighing c. 4.5 kg (Branch et al., 1996; ª 2012 Fauna & Flora International, Oryx, 46(1), 106–111 doi:10.1017/S0030605310001821 Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.139, on 29 Sep 2021 at 22:58:59, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605310001821 Diet of pumas in Patagonia 107 Pessino et al., 2001). During 1985–1994 the populations of Study area the plains vizcacha in the park declined by . 90% (Branch et al., 1996), and its occurrence as a prey item was reduced Phytogeographically the study area is in the Central by 70% in the puma diet (Pessino et al., 2001). Over the Patagonian District in the Patagonian province, where the same period an increase in the consumption of bigger prey characteristic vegetation is a mixed steppe of grassland and 1976 (the introduced wild boar Sus scrofa and red deer Cervus shrubs (Cabrera, ). The climate is dry and cold, with 1998 elaphus, and guanaco and smaller prey such as the big hairy strong western winds (Harris, ); mean annual temper- 17 armadillo Chaetophractus villosus and rodents) was ob- ature is °C and mean annual precipitation varies from 125 500 served (Branch et al., 1996; Pessino et al., 2001). A study in mm in the east to mm in the west. Our study was north-western Argentine Patagonia showed that most of conducted in three protected areas and two sheep ranches 1 the biomass consumed by pumas was of introduced species, in Santa Cruz province (Fig. ). The protected areas, which particularly the European hare and the red deer, and only are under the Argentine National Park Administration, 570 2 a small proportion was of native species, such as the big were the -km Monumento Natural Bosques Petrifica- 1 150 2 hairy armadillo and rodents (Novaro et al., 2000). The dos, the , -km Perito Moreno National Park and the 610 2 elevated consumption of introduced prey was the result of -km Monte Leo´n National Park; the latter was created 2000 their higher abundance and availability compared to that of in from a sheep ranch. The sheep ranches were the 400 2 25 100 native prey (Novaro et al., 2000). Such an imbalance can -km de Marzo Ranch, . km from the nearest increase until native prey do not interact significantly with protected area, the Monumento Natural Bosques Petrifica- 200 2 their natural predators and are therefore considered eco- dos, and the -km Doraike Ranch neighbouring Monte logically extinct (Estes et al., 1989). Leo´n National Park. The Monumento Natural Bosques 25 This concept is relevant for the conservation of extant Petrificados and the de Marzo Ranch are on the central communities because the loss of a species or its functional plateau of Santa Cruz, where shrub-steppe is the dominant role may substantially affect the abundance and population vegetation type. The Perito Moreno National Park is in the structure of other species in the community. For example, west of the province, where the Andean mountain range guanacos may have suffered local and ecological extinctions and the Patagonian steppe are the main vegetation types. throughout Patagonia (Novaro et al., 2000; Pessino et al., The Monte Leo´n National Park and the Doraike Ranch are 2001) because of human activities such as poaching and in the south-east, on the Atlantic coast, where the dominant livestock husbandry, which has displaced the guanaco vegetation type is shrub-steppe. towards less favourable foraging areas (Baldi et al., 2001; Travaini et al., 2007). Additionally, agriculture, oil exploi- tation and mining have altered habitats and made new areas accessible to sport hunters and poachers (Donadio & Buskirk, 2006), which could have accelerated the decline of native wildlife, both in density (Ya´n˜ez et al., 1986; Puig et al., 1997) and distribution (Pedrana et al., 2009). With the exception of the study of Novaro et al. (2000), in Argentine Patagonia the effect of introduced species on the diet of the puma has not been described. Based on their localized observations Novaro et al. (2000) concluded that the role of the guanaco and lesser rhea Pterocnemia pennata as prey for the puma had been supplanted by red deer, European hare and livestock (sheep, goats and horses), and they suggested that this may also be the case throughout this extensive and heterogeneous region. The purpose of our study was to examine the supposed ecological extinction of the puma’s native prey in southern Patagonia and to determine if the observations of Novaro et al. (2000) could be extrapolated to all of Argentine Patagonia. We analysed puma diet in three protected areas and two sheep ranches in Santa Cruz province.