Mamíferos de mediano y gran porte en corredores boscosos del pedemonte de yungas del noroeste argentino

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La transformación del ambiente natural constituye la principal amenaza para la conservación de muchas de las especies de mamíferos. La agricultura ha reducido la conectividad del piedemonte de Yungas con el Chaco, limitándola a corredores de hábitats naturales modificados que atraviesan una matriz de zonas transformadas. Mediante relevamientos con cámaras trampa, identificamos las especies medianas y grandes de mamíferos que utilizan corredores boscosos en dos sectores latitudinales del piedemonte de Yungas de Argentina. Estudiamos la diversidad de especies, la influencia de la distancia a través del corredor hasta el bosque continuo sobre la riqueza, cuantificamos similitudes en la composición y estructura de las comunidades entre ambas situaciones ambientales y evaluamos si los corredores constituyen zonas de paso o si los mamíferos establecen sus áreas de acción en los mismos. Registramos 22 especies en los corredores. Solo seis taxones registrados en bosque continuo no fueron documentados en los corredores, y tres fueron fotografiados solo en corredores. Para ambos sectores latitudinales, la equitatividad fue levemente mayor en corredores (aunque las diferencias fueron significativas solo en el sector norte), mientras que la riqueza de especies mostró tendencias opuestas entre sectores latitudinales, siendo mayor en el bosque del sector norte pero menor en el bosque del sector sur (aunque las diferencias no fueron significativas en ningún caso). No encontramos una influencia de la distancia al bosque continuo sobre la riqueza de mamíferos, ni diferencias importantes en la composición y estructura de las comunidades de ambas situaciones ambientales. En el norte, Dasyprocta punctata fue más frecuente en bosques continuos, mientras que Mazama gouazoubira y Leopardus pardalis prefirieron los corredores. En el sur, Leopardus pardalis y Pecari tajacu fueron más frecuentes en bosque continuo, mientras que Didelphis albiventris y las especies omnívoras utilizaron más los corredores. No encontramos diferencias significativas entre especies generalistas y especialistas en el uso de estos hábitats. Nuestro trabajo constituye la primera aproximación a esta temática en la región de las Yungas, aportando información relevante para el establecimiento de políticas de conservación.


Medium and large sized mammals in forested corridors of the yungas’ piedmont of northwestern Argentina. The transformation of the natural environment constitutes the main threat for the conservation of many mammal species. Agriculture has reduced the contact area of the Yungas piedmont forests with the Chaco region to corridors of modified natural habitats which cross the matrix of transformed areas. With camera traps surveys, we identified medium and large sized mammal species that use forested corridors in two latitudinal sectors of the Yungas piedmont forests in Argentina. We studied species diversity, the influence of the distance along the corridor to the continuous forest on species richness, and we evaluated whether the corridors are areas with established populations of these mammals. We recorded 22 species in the corridors. Only six species registered in the continuous forest were not recorded in the corridors, and three were only photographed in the corridors. For both latitudinal sectors, equitability was slightly higher in corridors (although differences only were significant in the northern sector) while species richness was different between latitudinal sectors, higher in the forest of the northern sector, but lower in the forest of the southern sector (although the differences were not significant in any case). We did not find any influence of the distance to the continuous forest on the richness of mammal species nor important differences in the composition and structure of the communities of both environmental situations. In the northern portion, Dasyprocta punctata was more frequently recorded in the continuous forest, whereas Mazama gouazoubira and Leopardus pardalis were more frequently recorded in the corridors. In the southern one, Leopardus pardalis and Pecari tajacu were more frequently recorded in the continuous forest, while Didelphis albiventris and the omnivore species more in the corridors. We did not find significant differences in the use of these habitats between the generalist and specialist species. This is the first study on this topic in the Yungas of Argentina, providing relevant information for the establishment of conservation policies.

Incertidumbre taxonómica de un primate neotropical; el caso de Ateles fusciceps rufiventris Sclater, 1871 (Primates: Atelidae)

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La taxonomía de los monos araña (Ateles spp.) en el Pacífico ha sido un tema de controversia en la literatura científica, con varias hipótesis derivadas de análisis biogeográficos, morfológicos y genéticos, tendiendo a volver difusa la certidumbre concerniente a la identidad específica de este taxón, lo cual complejiza la toma de decisiones para la conservación de este grupo de primates en el Neotrópico. Por lo tanto, en este estudio presentamos una revisión sistemática que soporta que las poblaciones de mono araña de la porción norandina del Pacífico deberían atribuirse a Ateles fusciceps rufiventris.


Taxonomic uncertainty in a Neotropical primate: the case of Ateles fusciceps rufiventris Sclater, 1871 (Primates: Atelidae). The taxonomy of spider monkeys (Ateles spp.) in the Colombian Pacific region has been controversial in the scientific literature, with several hypotheses derived from biogeographical, morphological and genetic analyses. Uncertainty concerning the specific identity of this taxon makes decision making more difficult for the conservation of this group of primates in the Neotropics. In this study, we present a systematic review which supports that populations of spider monkeys of the north-Andean portion of the Pacific should be assigned to Ateles fusciceps rufiventris.

Ant diversity in the diet of giant anteaters, Myrmecophaga tridactyla (Pilosa: Myrmecophagidae), in the Iberá Nature Reserve, Argentina

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The giant anteater, Myrmecophaga tridactyla, globally categorized as a vulnerable species, has disappeared in several regions of its original distribution in Argentina. A program to reintroduce the species has been conducted in the Iberá Nature Reserve in Corrientes province since 2006. The diet of released giant anteaters was studied to determine the identity of their prey, and establish whether they have preference for ants or termites or, rather, prefer certain feeding habitats (e.g., open or closed). Twenty two fecal samples were randomly collected during 2008–2013, and heads and mesosomes were recovered. We identified 12 taxa of ants and only one taxon of termites. Observed taxa represent around 80% of the taxa expected to be eaten by anteaters. Camponotus was the most common ant genus, and Acromyrmex and Solenopsis were the numerically most abundant genera. The ant taxa ingested by M. tridactyla were reflective of their natural availablility in the area, suggesting that giant anteaters had no preference for any particular prey. They mainly consumed ant species of the genera Solenopsis, Camponotus and Acromyrmex with conspicuous nests that occur mostly in open habitats of the reserve and not in the most preferred habitat (forest). One possible explanation is that anteaters reduce their foraging search time, and consequently the time they are out in open habitat, so avoiding predation risk and thermal injuries. Thus, conservation of both open and closed habitats would be essential for maintaining the reintroduced populations of giant anteaters.


Diversidad de hormigas en la dieta del oso hormiguero gigante, Myrmecophaga tridactyla (Pilosa: Myrmecophagidae), en la Reserva Natural Iberá, Argentina. El oso hormiguero gigante, Myrmecophaga tridactyla, es una especie catalogada como vulnerable tanto a nivel mundial como en Argentina, donde desapareció en varias regiones de su distribución nativa. Un programa de reintroducción de especies se lleva a cabo desde 2006 en la Reserva Natural Iberá en Corrientes. Se estudió la dieta de los osos hormigueros gigantes liberados para determinar la identidad de sus presas y conocer si poseen preferencia por hormigas o termitas o por sitios de alimentación (abiertos o cerrados). Se colectaron 22 muestras de heces entre 2008–2013, recuperándose cabezas y mesosomas. Estos tagmas fueron identificados en 12 taxones de hormigas y uno de termitas. Los taxones observados representaron el 80% de lo esperado a ser ingerido por los osos. Camponotus fue el género más común, y Acromyrmex y Solenopsis los más abundantes numéricamente. Los taxones ingeridos por M. tridactyla se relacionaron positivamente con la disponibilidad del área, sugiriendo que los osos no tienen preferencia por presas en particular. Principalmente consumieron hormigas con nidos conspicuos de Solenopsis, Camponotus y Acromyrmex que se encuentran mayormente en áreas abiertas de la reserva y no en el bosque, hábitat preferido. Creemos que debido a la alta disponibilidad de esas presas, los osos reducen su tiempo de búsqueda de forrajeo, y por ende, su tiempo de permanencia en áreas abiertas, evitando así riesgos de prelación y daños térmicos. La conservación de ambos hábitats, abiertos y cerrados, sería esencial para el mantenimiento de la población reintroducida de osos hormigueros gigantes.

Environmental predictors of demography in the tuco-tuco of the dunes (Ctenomys flamarioni)

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We studied the population ecology of the South American subterranean rodent Ctenomys flamarioni at the Taim Ecological Station, Rio Grande do Sul, Brazil. A capture-mark-release program was conducted in two different time periods: (A) from February 2004 to November 2005 and (B) from December 2011 to March 2013; as a result, a total of 131 individuals were marked. Some population parameters remained constant (average population density, survival rate), while others fluctuated (sex ratio, estimated population size, recruitment and mortality). The second sampling period had higher estimated population size and mortality and reduced recruitment compared to the first period. Sex ratio did not differ significantly from 1:1 in period A, but showed a significant departure from 1:1 in period B, with a greater number of females captured. Ctenomys flamarioni populations seem to be substantially influenced by local environmental factors; density was positively associated with temperature and negatively associated with precipitation. This is the first report of variation through time in reproduction and population rates for this species, which is under increasing risk of extinction.


Influência de variáveis ambientais sobre a demografia do tuco-tuco das dunas (Ctenomys flamarioni). Nós estudamos a ecologia populacional do roedor subterrâneo sul-americano Ctenomys flamarioni na Estação Ecológica do Taim, Rio Grande do Sul, Brasil. Um programa de captura-marcação-recaptura foi realizado em dois períodos diferentes: (A) de fevereiro de 2004 a novembro de 2005 e (B) de dezembro de 2011 a março de 2013. Como resultado, um total de 131 indivíduos foram marcados. Alguns parâmetros populacionais permaneceram constantes (densidade populacional média, taxa de sobrevivência), enquanto outros flutuaram (razão sexual, tamanho estimado da população, recrutamento e mortalidade). O segundo período de amostragem apresentou maior tamanho populacional estimado e mortalidade, por outro lado mostrou menor valor de recrutamento em relação ao primeiro período. A razão sexual não diferiu significativamente de 1:1 no período A, mas mostrou um desvio significativo de 1:1 no período B, com um maior número de fêmeas capturadas. As populações de Ctenomys flamarioni parecem ser substancialmente influenciadas por fatores ambientais locais; a densidade foi positivamente associada à temperatura e negativamente associada à precipitação. Este é o primeiro relato de variação ao longo do tempo nas taxas de reprodução e população para esta espécie, que está sob-risco crescente de extinção.

Circannual sex distribution of the Brazilian free-tailed bat, Tadarida brasiliensis (Chiroptera: Molosssidae), suggests migration in colonies from Uruguay

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In the Northern Hemisphere, Tadarida brasiliensis is a migratory species, but there are no published data about its migration behavior in Uruguay. Using field data, we found significant and consistent seasonal variation in colony sex ratios across Uruguay. Males composed the majority of colonies sampled in Uruguay during the cold season, whereas females proportionally outnumbered males in these colonies during the warm season. Individuals present during the cold season remain active, and our evidence suggests females migrate out of Uruguay in winter. This is the first contribution to knowledge about circannual use of roosts by T. brasiliensis in Uruguay.


Distribución circanual de sexos del murciélago de cola libre brasilero, Tadarida brasiliensis (Chiroptera: Molossidae), sugiere migración en colonias de Uruguay. Tadarida brasiliensis es una especie migratoria en el hemisferio norte, pero no existen datos publicados al respecto para Uruguay. A partir de datos de campo mostramos que existe una variación significativa en la composición por sexos a lo largo del año en las colonias del país. Durante la estación fría se observa una composición mayoritariamente masculina de las colonias, mientras que en la estación cálida el patrón se invierte. Se verifica que los individuos presentes durante el invierno están activos todo el año y nuestra evidencia sugiere que las hembras migran fuera de Uruguay durante el invierno. Esta es la primera contribución al conocimiento del uso anual de refugios por esta especie en Uruguay.

On a collision course: the vulnerability of bats to roadkills in Brazil

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In Brazil, studies on roadkills are recent and usually restricted to lists of species found at some road stretch. Among mammals, medium- and large-sized species have received greater attention. The present study aimed at presenting the first list of bat roadkills in Brazil, including comments on the traits that may cause roadkills. We recorded 415 deaths from 44 species of seven families in all Brazilian biomes. We did not observe a relationship between body size or type of flight with the number of bat-vehicle collisions. Frugivore was the trophic guild most victimized, possibly due to greater natural abundance, foraging in low height airspace, and capacity to make long-distance movements. The elevated number of species recorded indicates that these roads may exert a negative effect on bat fauna. We encourage road ecologists and environmental agencies to include bats in their fauna monitoring of road infrastructure and request to make more accurate estimates of this impact.


Em rota de colisão: a vulnerabilidade de morcegos à atropelamentos no Brasil. No Brasil os estudos sobre atropelamentos de fauna são recentes e, na maioria dos casos, restritos a lista de espécies encontradas em alguns trechos de rodovias. Dentre os mamíferos, espécies de médio e grande porte têm recebido maior atenção. O presente estudo apresenta a primeira lista de morcegos atropelados no Brasil, incluindo comentários sobre os fatores que podem causar os atropelamentos. Nós registramos 415 óbitos de 44 espécies e sete famílias em todos os biomas brasileiros. Nós não observação relação entre o tamanho corporal e o tipo de voo com o número de colisões entre veículos e morcegos. Morcegos frugívoros foram os mais vitimados, possivelmente, em virtude de sua maior abundância natural, por forragear em baixas alturas e pela elevada capacidade de movimentação. O alto número de espécies indica que as estradas podem exercer um viés negativo sobre a quiropterofauna. Nós incentivamos que pesquisadores e agências ambientais incluam morcegos no monitoramento de fauna em infraestruturas viárias e solicitem estimativas mais precisas desse impacto.

First record of Lonchophylla bokermanni (Chiroptera, Phyllostomidae) for the Caatinga biome

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Lonchophylla bokermanni is known from three localities in the southern portion of the Serra do Espinhaço, all located in the Cerrado of Minas Gerais. Based on recent material from two localities in the Caatinga of Bahia, northeastern Brazil, we report the species occurrence in the northern portion of Serra do Espinhaço. These new records extend the species distribution by more than 840 km and represent the first records of L. bokermanni in the Caatinga biome. The localities we report here are under severe anthropic pressure, and this distribution extension should not inhibit conservation efforts for the species.


Primeiro registro de Lonchophylla bokermanni (Chiroptera, Phyllostomidae) para o bioma Caatinga. Lonchophylla bokermanni é conhecida para três localidades na porção sul da cadeia de montanhas da Serra do Espinhaço, com todos os registros no Cerrado de Minas Gerais. Com base em registros recentes provenientes de duas localidades na Caatinga da Bahia, nordeste do Brasil, registramos a espécie na porção norte da Serra do Espinhaço. Os novos registros ampliam a distribuição da espécie em mais de 840 km, representando o primeiro registro de L. bokermanni para a Caatinga. As novas localidades reportadas estão sob grande pressão antrópica. Assim, a ampliação da distribuição não deve inibir estratégias de conservação para a espécie.

Effects of patch attributes on the richness of medium and large-sized mammals in fragmented semi-deciduous forest

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We evaluated the effect of patch attributes on the richness of medium- and large-sized mammals in semi-deciduous forest patches in the southern of Goiás state, Brazil. We surveyed 14 semi-deciduous forest patches (35 to 869 ha) from January to December 2015. Medium- and large-sized mammal were sampled through direct observation, tracks, feces and burrows. In each semi-deciduous forest patch, we measured total area and core area (in hectare), degree of isolation (in meters) and connectivity (patches connected to riparian forest versus isolated patches). We recorded 22 species of medium- and large-sized mammals. Species richness was positively related to the core area of the patches. Patch size had a significant influence on species richness showing that this attribute is important to maintain community structure. Therefore, the fragmented landscape of southern Goiás still harbors a rich fauna of medium- and large-sized mammals.


Efeitos de atributos de mancha na riqueza de mamíferos de médio e grande porte em florestas semidecíduas fragmentadas. Neste estudo, nós avaliamos o efeito dos atributos da mancha sobre a riqueza de mamíferos de médio e grande porte em manchas de floresta semidecidual no sul do estado de Goiás, Brasil. Quatorze manchas (de 35 a 869 ha) foram estudados durante janeiro a dezembro de 2015. Mamíferos de médio e grande porte foão inventariados por meio de observações diretas, pegadas, fezes e tocas. Em cada mancha de floresta semidecidual foi mensurada a área total e área núcleo (em hectare), grau de isolamento (em metros) e conectividade (manchas conectadas a mata ripária versus manchas isoladas). Vinte e duas espécies de mamíferos de médio e grande porte foram registradas. A riqueza de espécies esteve positivamente correlacionada com a área núcleo do fragmento. O tamanho da área teve uma influência significativa sobre a riqueza de espécies, mostrando que esse atributo é importante para manter a estrutura da comunidade. Portanto, a paisagem fragmentada do sul de Goiás abriga uma rica e ameaçada fauna de mamíferos de médio e grande porte.

Mamíferos terrestres en islas del Atlántico sudoccidental, Patagonia, Argentina

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El objetivo de este trabajo fue relevar las especies de mamíferos terrestres presentes en las principales islas del Parque Interjurisdiccional Marino Costero Patagonia Austral (PIMCPA). Este estudio se desarrolló en las islas Leones, Tova, Tovita e islas menores aledañas. Los pequeños mamíferos fueron capturados con trampas; estos y otras especies fueron también registrados a partir de transectas de caminatas y análisis de egagrópilas de aves rapaces. Se registraron siete especies de mamíferos terrestres. En isla Leones se encontraron tres especies: peludo (Chaetophractus villosus), murciélago orejudo chico (Histiotus montanus) y rata noruega (Rattus norvegicus), mientras que en las islas Tova y Tovita se hallaron cuatro: gato (Felis catus), cuis chico (Microcavia australis), conejo (Oryctolagus cuniculus) y piche (Zaedyus pichiy). La presencia de especies introducidas podría generar conflictos con la avifauna marina que nidifica en estas islas.


Land mammals on islands of the southwestern Atlantic, Patagonia, Argentina. The aim of this study was to survey the species of terrestrial mammals in the main islands of the Parque Interjurisdiccional Marino Costero Patagonia Austral (PIMCPA). This study was conducted in Leones, Tova, Tovita and surrounding smaller islands. Small mammals were surveyed with trapping; these and other species were documented with walking transects and analysis of raptor pellets. Seven species of land mammals were recorded in total. In Leones island three species were found: big hairy armadillo (Chaetophractus villosus), small big-eared brown bat (Histiotus montanus) and Norway rat (Rattus norvegicus), while in Tova and Tovita islands four species were identified: feral cat (Felis catus), southern mountain cavy (Microcavia australis), European rabbit (Oryctolagus cuniculus) and pichi (Zaedyus pichiy). The presence of introduced species could generate conflicts with marine birds nesting in these islands.

The giant armadillo (Priodontes maximus) in the Argentine Chaco

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The giant armadillo (Priodontes maximus) is a difficult species to study because of low population densities, combined with nocturnal and fossorial habits. No systematic population studies have been undertaken to date in Argentina. Our objectives were to evaluate the species’ presence, relative abundance, and temporal activity patterns across five locations with different levels of human disturbance and legal protection in the Argentine Chaco. Between June 2006 and January 2014, we completed 10 surveys, using camera trap and/or track plots, searches for burrows and tracks, and observations by local people and park rangers. We used camera trap records to determine presence, relative abundance (records / 100 camera days) and activity patterns. We only recorded the species at three locations: Copo National Park, Aborigen Reserve and La Fidelidad Resource Reserve. At the Aborigen Reserve we documented burrows and tracks but obtained no photographs. At Copo and La Fidelidad we estimated relative abundance at 0.08 and 0.40 records per 100 camera days, respectively. We did not record giant armadillos near the edges of La Fidelidad, nor in the two locations with greater human disturbance. Camera trap records indicate that giant armadillos in the Argentine Chaco are strongly nocturnal. The population status of giant armadillos in Argentina is a matter of concern. With few or no records at other study locations, La Fidelidad may harbor one of the few relict populations of giant armadillos in the Argentine Chaco.


El tatú carreta (Priodontes maximus) en el Chaco argentino. El tatú carreta (Priodontes maximus) es una especie difícil de estudiar debido a sus hábitos nocturnos y fosoriales y a sus bajas densidades poblacionales. En Argentina no hay estudios poblacionales sistemáticos realizados previamente. Nuestro objetivo fue determinar la presencia, abundancia relativa y patrones de actividad temporal en cinco sitios con distinto grado de intervención humana y categoría de protección legal en el Chaco argentino. Entre junio de 2006 y enero de 2014 realizamos 10 muestreos utilizando cámaras-trampa, colocación de huelleros, recorridos de búsqueda de cuevas y rastros e información de pobladores locales y guardaparques. Utilizamos datos de cámaras-trampa para determinar la presencia, abundancia relativa (registros / 100 días cámara) y patrones de actividad. La especie fue registrada solamente en tres sitios: el Parque Nacional Copo, la Reserva Aborigen y la Reserva de Recursos La Fidelidad. En la Reserva Aborigen registramos cuevas y huellas, pero no obtuvimos fotografías. En Copo y en La Fidelidad estimamos la abundancia relativa en 0.08 y 0.40 registros cada 100 días-cámara respectivamente. No registramos tatúes ni en los bordes de La Fidelidad, ni en los dos sitios con mayor grado de disturbio humano. Los registros fotográficos indican que el tatú carreta es marcadamente nocturno en el Chaco Argentino. La situación poblacional del tatú carreta en Argentina es preocupante. Los escasos o nulos registros obtenidos en las otras áreas sugieren que La Fidelidad podría conservar uno de los pocos relictos poblacionales de tatú carreta en el Chaco Argentino.