New Data on Armadillos (Xenarthra: Dasypodidae)

New Data on Armadillos (Xenarthra: Dasypodidae)

grazing on the natural vegetation. ªere is evidence New Data on Armadillos (Xenarthra: Dasypodidae) that grazing by domestic herbivores has been modify- for Central Patagonia, Argentina ing the vegetation and accelerating soil degradation processes since the beginning of the twentieth cen- Agustín M. Abba tury (e.g., Beeskow et al., 1987; Rostagno and Del Marcela J. Nabte Valle, 1988; Bisigato and Bertiller, 1997). Daniel E. Udrizar Sauthier Most of Patagonia is dominated by strong and Abstract constant west winds. Precipitation levels decrease from west to east; most of the region receives less Armadillos represent the most diverse family of xen- than 200 mm per year. Mean annual temperature arthrans. Although many studies have been done on varies between 12°C in the northeastern part and these mammals, several topics, such as their local 3°C toward the south (Paruelo et al., 1998). How- distribution, natural history, behavioral ecology and ever, minimum temperatures in the Somuncurá pla- conservation, remain poorly known. Chaetophractus teau are among the coldest recorded for Argentina villosus and Zaedyus pichiy are the most common (−35°C in Maquinchao, Río Negro province). armadillos in extra-Andean Patagonia, a vast area in southern Argentina and Chile that encompasses dif- Today, four species of armadillos are known to inhabit ferent ecosystems and has been modified by human Patagonia (including Argentina and Chile): Chaeto- activities, mainly by sheep grazing. In this work we phractus vellerosus (Gray, 1865), C. villosus (Desmar- present new data on the distribution, natural his- est, 1804), Chlamyphorus truncatus (Harlan, 1825), tory, conservation, and ecology of C. villosus and and Zaedyus pichiy (Desmarest, 1804). Ch. truncatus Z. pichiy from central Patagonia (Chubut and Río and C. vellerosus occur only rarely (Abba and Viz- Negro provinces, Argentina). We registered 60 locali- caíno, 2008), but C. villosus and, especially, Z. pichiy ties for C. villosus and 35 for Z. pichiy that confirm are two typical medium-sized mammals from Pata- their presence in wide sectors of central Patagonia. gonia (Cabrera and Yepes, 1940; Daciuk, 1974). Furthermore, we confirmed that these two armadillo According to bibliographic records and voucher species suffer high rates of mortality due to their use material from Argentinean mammal collections, as a protein source, hunting by dogs, road traffic, and only 51 localities have been reported for these two poisoning, among others. We conclude that their species in Patagonia (Abba and Vizcaíno, 2008; populations are at risk of overexploitation and local Abba, unpublished data). extinction. ªe basic knowledge provided here will be a first step towards the conservation of these char- In this work, we present data on new localities, natu- acteristic Patagonian mammals. ral history, conservation, and ecology of C. villosus and Z. pichiy from central Patagonia (Chubut and Keywords: Chaetophractus villosus, Zaedyus pichiy, new Río Negro provinces, Argentina). records, distribution. Materials and Methods Introduction Fieldwork was carried out during the summers of Armadillos (Mammalia: Dasypodidae) represent the 2005 to 2007 as part of the dissertation research of most diverse family of recent xenarthrans (Wetzel, two of the authors (MJN and DEUS) and in con- 1985a, b). Although many scientific publications junction with the project “Postglacial Patagonia: exist on these species (see Superina, 2010), several evolutionary responses of small mammals to climate topics, such as the natural history, local distribution, change” (National Geographic Society, grant number behavioral ecology, and conservation, remain poorly 7813-05). Data were collected opportunistically studied (McDonough and Loughry, 2008). and through observation of individuals of Z. pichiy and C. villosus in different areas of central Patagonia, Extra-Andean Patagonia occupies an area of mainly the Chubut river basin, Somuncurá plateau, 750,000 km2 and encompasses different ecosystems, and Península Valdés. Additionally, we used infor- from grasslands to shrub-steppes and semi-desert. mation from interviews with rural settlers to obtain Phytogeographically, the area includes the Patagonian information on the behavior, habits, diet, abundance, steppe, the Monte shrub-steppes, and scrublands and hunting of armadillos; the detailed results of (Cabrera, 1976). Human activities have modified these interviews are being analyzed and will be pub- most of the Patagonian region, most notably by sheep lished elsewhere. Edentata no. 11(1) • 2010 11 Collected material, such as skeletal remains, are in Zaedyus pichiy Desmarest, 1804 preparation and will be added to the Mammal Collec- tion of Centro Nacional Patagónico, Chubut, Argen- Common name: pichi, piche, piche de oreja corta, tina. Additional evidence is registered in the field piche patagónico. catalogue of Marcelo Carrera and Marcela J. Nabte. Local conservation status: Least Concern (LC). Species Results widespread and abundant (Diaz and Ojeda, 2000). Chaetophractus villosus Desmarest, 1804 Global conservation status: Near ªreatened (NT). ªis species is relatively widespread and is present in Common name: large hairy armadillo, peludo, quir- a great number of protected areas (Heinonen Forta- quincho grande. bat and Chébez, 1997). However, it is hunted exten- sively, especially in the northern and eastern portion Global and local conservation status: Least Concern of its range, and local extinctions have been recorded (LC). Listed as LC because of its (1) wide distribution in some areas (Fonseca and Aguiar, 2004; Superina, and thus, presumed large population; (2) occurrence 2008; Superina and Members of the IUCN/SSC in a number of protected areas; and (3) tolerance of a Edentate Specialist Group, 2008). Less information large degree of habitat modification. Also, it is unlikely is available about declines in southern areas. Over- to be declining fast enough to qualify for listing in a all, this species is estimated to have declined signifi- more threatened category (Fonseca and Aguiar, 2004). cantly, primarily due to intense hunting (Fonseca and Aguiar, 2004). Reported uses: hunting for food. Traffic accidents and poisoning with substances used to kill foxes were Reported uses: hunting for food. Traffic accidents and reported as other causes of non-natural mortality. hunting by domestic dogs were reported as other causes of non-natural mortality. New records: 60 (see Table 1 and Fig. 1). Most records were observations of live individuals or collected car- New records: 35 (see Table 1 and Fig. 1). Similar to casses. Only five animals could be captured and sexed; C. villosus, most observations were of wild individuals three were males and two were females. None of the that could not be captured. ªe gender of five ani- latter was pregnant at the moment of capture in fall. mals was determined, four of them being males. One female captured during winter was not pregnant. Habitat: this species was observed, captured, and reported in all habitat types (steppes, monte shrub- Habitat: Z. pichiy was observed, captured, and steppes, and scrublands), but was more common in reported in all habitat types (steppes, monte shrub- the monte shrub-steppes. steppes, and scrublands) but seemed to be more common in steppes. Observations: local people list many negative impacts of C. villosus and frequently persecute it as a pest. One Observations: in contrast to C. villosus, rural settlers important complaint is related to its burrows, especially eagerly hunt this species because it is “clean” (i.e., it to the risk of livestock (sheep) and horses stepping into does not ingest carrion) and its meat is more palat- them and breaking their legs. Other common con- able. Many rural families will spend the afternoon cerns include disease transmission and possible attacks hunting pichis and may catch four or five animals on young sheep. In addition, C. villosus was found per day. ªey eat the meat and use the fat for frying. to negatively affect bird populations, both domestic (chicken) and wild (e.g., penguins in the northern part In Península Valdés, pichis are more abundant in of Península Valdés at San Lorenzo ranch) because of sandy areas. ªey are mainly found in the southern their consumption of eggs and chicks. part of Península Valdés and become scarcer toward its northern portion. In central Patagonia, pichis are Although local people view “peludos” as unclean rarely seen aboveground during cold periods (fall and because they eat carrion, garbage and pichis, many winter). Pichis are frequently observed eating plants, still use this armadillo as an important protein source. mainly Condalia microphylla and Arjona tuberose, and In many tourist areas (e.g., Punta Norte, Península insect larvae (Tenebrionidae, Nyctelia spp.). Remains Valdés) “peludos” are a favorite because they are nei- of several juvenile pichis were found below nests of ther aggressive nor shy, and will eat from the hand Black-chested Buzzard-Eagles (Geranoetus melanoleu- of people. cus), as observed by Saggese and De Lucca (1994). 12 Edentata no. 11(1) • 2010 Discussion Perhaps, its higher abundance is a consequence of its successful invasion of Patagonia (Williamson and Like all armadillos, C. villosus and Z. pichiy have low Fitter, 1996). body temperatures, low basal metabolic rates, and high thermal conductances (McNab, 1985). Given On the other hand, Z. pichiy, the typical Patago- the low ambient temperatures in Patagonia, these nian armadillo, is registered

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