Natural History of the Chinchilla Genus (Bennett 1829). Considerations of Their Ecology, Taxonomy and Conservation Status
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Gayana 78(2): 135-143, 2014. ISSN 0717-652X Natural history of the Chinchilla genus (Bennett 1829). Considerations of their ecology, taxonomy and conservation status Historia natural del género Chinchilla (Bennett 1829). Consideraciones de su ecología, taxonomía y estado de conservación PABLO VALLADARES FAÚNDEZ1*, ÁNGEL SPOTORNO OYARZÚN2 & CARLOS ZULETA RAMOS 3 1Departamento de Biología, Facultad de Ciencias, Universidad de Tarapacá. Avenida General Velásquez 1775, Arica, Chile. 2Laboratorio de Citogenética Evolutiva, Programa de Genética Humana, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile. 3Departamento de Biología, Facultad de Ciencias, Universidad de La Serena, Casilla 599, La Serena, Chile. *Email: [email protected] ABSTRACT Over the last years there has been new and valuable information in both wild chinchillas, however this is still insuffi cient for effective protection. In this paper we review some fundamental aspects of its natural history, synthesizing and delivering new information about their ecology, taxonomy and conservation status, based on the review of available literature, and fi eld data collection. In relation to their ecology we have been identifi ed new colonies of both species, for scientifi c research as well as environmental technical reports. For most of these colonies we identifi ed vegetation to which they are associated, predators and other sympatric rodent species. The taxonomy of these species is controversial. A proposal was submitted to ICZN in 2003, and the recommendations were to describe a neotype for genus and species, but the original specimens described by Bennett (1829), Lichtenstein (1830) and Waterhouse (1844) are in museums from Europe and should be considered as syntypes. Conservation status of both species is critically endangered because most colonies are threatened by mining exploitation. Therefore, it is essential to explore new regions to identify new colonies and compare them with modern methods such as molecular markers. Finally, with this information we argue the need to develop a conservation programs for both species; it should consider critical areas of their biology, such as ecology, genetics and reproduction. KEYWORDS: Chinchilla, conservation plans, critical endangered, distribution, endemism, new colonies. RESUMEN En los últimos años se ha generado nueva y valiosa información de las dos especies silvestres de chinchillas; sin embargo ésta sigue siendo insufi ciente para una protección efectiva. En este trabajo hacemos una revisión de algunos aspectos fundamentales de su historia natural, sintetizando y entregando nuevos antecedentes de su ecología, taxonomía y estado de conservación, en base a la revisión de la literatura disponible, y toma de datos en el campo. En relación a su ecología, hemos identifi cado nuevas colonias de ambas especies, tanto por investigación científi ca como por reportes técnicos ambientales. Para la mayoría de esas colonias se ha identifi cado la vegetación a la que están asociadas, depredadores y otras especies de roedores simpátridos. La taxonomía de ambas especies ha sido controversial. Una propuesta fue sometida a la ICZN en el 2003 y las recomendaciones fueron describir un neotipo para el género y ambas especies; sin embargo, los especímenes originales descritos por Bennett (1829), Lichtenstein (1830) y Waterhouse (1844) existen en museos de Europa y deben ser considerados como los respectivos sintipos. Finalmente, el estado de conservación de estas especies ha sido catalogado como críticamente en peligro tanto por instituciones nacionales como internacionales, esto debido a que la mayoría de las colonias son pequeñas, fragmentadas y aisladas, sin embargo, ahora la mayor amenaza es la relación geográfi ca de las nuevas colonias con áreas de explotación minera. Se argumenta con esta información la necesidad de desarrollar un programa de conservación de ambas especies, que considere ámbitos fundamentales de la biología de la especie, tales como la ecología, genética y reproducción. PALABRAS CLAVES: Chinchilla, conservation plans, critical endangered, distribution, endemism, new colonies. 135 Gayana 78(2), 2014 INTRODUCTION METHODS The Chinchilla genus (Bennett 1829) comprises two wild and To evaluate the ecology and conservation status of both endemic species of Chile, Chinchilla chinchilla (Lichtenstein species, we revisited scientifi c information (e.g. Jiménez 1830) commonly known as short-tail or andean chinchilla, 1987, 1989, 1994, 1995, 1996; Spotorno et al. 1998; Cortés and C. lanigera (Molina 1782), commonly known as the et al. 2002; Spotorno et al. 2004a,b; Valladares 2012; long-tail or coastal chinchilla. Both chinchillids species had Valladares et al. 2012; Tirado et al. 2012) and technical and a wide distributions; short tail chinchilla includes historical public reports. In other hand, we took fi eld data to assess distribution from Chile, Argentina, Peru and Bolivia (Chacón the vegetation associated with the colonies of chinchillas, 1892; Walle 1914; House 1953; Grau 1986; Jiménez 1996; as well as the sympatric species of rodents and predators Anderson 1997; Eisenberg & Redford 2000; Parera 2002; (Valladares et al. 2014). Woods & Kilpatrick 2005) and coastal chinchilla ranges from Choapa river (32°S) to north Potrerillos (26°S) (Grau To evaluate the taxonomy, we assessed old papers and collect 1986; Jiménez 1996). Actually the distribution is restricted specifi c information from curators of European and South to few, small and fragmented colonies (Valladares 2012; American collections, for example the National Museum of Valladares et al. 2012). Natural History, Leiden, Holland; Natural History Museum of London, England, and Museum für Naturkunde, Leibniz In relation to ecology, the knowledge for both species is Institut for Research on Evolution and Biodiversity at the very poor (Jimenez 1996). Studies conducted during the Humboldt University, Berlin, Germany, Museo Argentino last few decades have been restricted to ecophysiology de Ciencias Naturales “Bernardino Rivadavia”, Argentina. (Cortés et al. 2000; Ostojic et al. 2002; Cortés et al. 2003), diet (Cortés et al. 2002; Tirado et al. 2012) and distribution (Valladares 2012; Valladares et al. 2012; Valladares et al. RESULTS 2014). There are little information about social behavior, predators, competitive species and null information about ECOLOGY temporal abundance. Colonies from Las Chinchillas National Reserve were characteristic by ranging between 0,9 to 10.7 individuals/ About the taxonomy, the major biological questions is ha. Most of the scattered colonies were located on steep and the number of species of chinchillas to be recognized dry equatorial-facing slopes, where long-tail chinchillas eat (Anderson 1997), one (Osgood 1941, 1943, Allen 1942); the succulent bromeliad Puya berteroniana. Their refuges two (Cabrera &Yepes 1960; Cabrera 1961; Spotorno et corresponded to rock crevices and boulder piles (Jiménez al. 2004a), or three (Prell 1934a; Bidlingmaier 1937), but 1987, 1989, 1994, 1995, 1996). The main plant species according to Miller et al. (1983) this taxonomic issue could eaten by C. lanigera was the perennial graminoid Nassella never be resolved because there were no wild colonies. chilensis, and secondarily Heliotropium stenophyllum, Other unresolved topics in taxonomy is the determination of Lobelia polyphylla, Bridgesia incisifolia and Adiantum a neotype for the Chinchilla genus (Bennet 1829), lanigera chilense (Cortés et al. 2002). They coexisted with a diverse (Molina 1782) and chinchilla (Lichtenstein 1830) species, assemblage of rodents such as Abrocoma bennetti, Abrothrix to contribute to the taxonomic stability suggested by the olivaceus, A. longipilis and Octodon degus (Muñoz- International Commission on Zoological Nomenclature Pedreros & Gil 2009). The main predators of the chinchillas (ICZN - case 3278; Valladares & Spotorno 2003). in Coquimbo region were the foxes Lycalopex culpaeus and L. griseus (Muñoz-Pedreros & Gil 2009). Other biological The critical conservation status for both species is derived aspects such as reproduction, growth, and dispersion are by the more than 20 million specimens that were killed unknown. The diet as well as predators of the small and only in Chile at the beginning of twentieth century (Albert isolated colony at La Higuera are unkown. In relation to 1900, 1901; Iriarte & Jaksic 1986). Although both species the Atacama colony, it was located 44 km from the coast, were considered extinct during 1960´s, C. chinchilla was and inhabits in the middle of a very arid hill, approximately rediscovery by Spotorno et al. (1998) and Valladares et al. 1150 m in height, and surrounded by extensive dunes of the (2012); and C. lanigera by Mohlis (1983) and Spotorno et Atacama Desert (Valladares et al. 2014). Forty two points al. (2004a). with feces, footprints and/or wallows were identifi ed, nine of them showing recent activity. The vegetation was identifi ed In this work we present a timely update on past reviews of as Heliotropium sclerocarpum, Tetragonia microcarpa, information, which will be a useful tool for both planning Gymnophytum fl exuosum, Nolana sp., and particularly future conservation efforts and mitigation of human– Eriocyse aurata, probably the main source of water and wildlife confl icts, such as the mining exploitation. food, with 87% of its cactus gnawed by rodents. No other 136 Natural history of the Chinchilla genus: PABLO VALLADARES FAÚNDEZ ET AL. sympatric species