Keyword: Myrmecophaga tridactyla

Variação espacial e sazonal de atropelamentos de mamíferos no Bioma Cerrado, rodovia BR 262, sudoeste do Brasil

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Foram examinadas a composição e abundância das espécies de mamíferos atropeladas em dois trechos da rodovia BR 262, a relação dos atropelamentos com a distância de centros urbanos, a escala espacial dos atropelamentos, a distribuição dos atropelamentos segundo a sazonalidade e a relação dos atropelamentos com o número de veículos. Os animais atropelados foram registrados durante 2 anos e 4 meses entre Campo Grande e Miranda, estado do Mato Grosso do Sul, sudoeste do Brasil. Ao todo foram registrados 231 espécimes de mamíferos distribuídos em 20 espécies, sendo Carnivora, Cingulata e Pilosa as principais ordens. Os atropelamentos foram mais intensos conforme o distanciamento dos grandes centros urbanos. Na análise de distribuição espacial e sazonal dos atropelamentos, Cerdocyon thous e Tamandua tetradactyla apresentaram picos definidos de atropelamentos em certos trechos da estrada, marcados sazonalmente. Não houve diferença na riqueza de espécies entre os trechos estudados nem entre as estações climáticas. Porém, o número total de atropelamentos se mostrou mais acentuado no trecho da rodovia que estava mais próximo ao Pantanal, com destaque para as ordens Carnivora e Pilosa. Em geral, houve mais atropelamentos durante o período chuvoso, com destaque para a ordem Cingulata. Recomendações de manejo são feitas com o objetivo de diminuir o efeito prejudicial da estrada, tais como uso de placas sinalizadoras de locais e épocas críticas de atropelamentos, uso de cercas de contenção de fauna em trechos críticos e facilitação para a movimentação da fauna através da rodovia, de modo seguro.

Spatial and seasonal variation of mammal road kill in the BR-262 highway, Cerrado biome, southwestern Brazil. The composition and abundance of mammal road kills were examined on two stretches of the BR-262 Federal Road, besides relationship between city distance and road kill, road-kill spatial distribution, seasonality effects, and relationship with vehicles daily volume. The killed animals were registered over 2 years and 4 months, between Campo Grande and Miranda, in southwestern Brazil. A total of 231 mammal specimens was found, which were distributed in 20 species, being Carnivora, Cingulata and Pilosa the main orders. The road-kill frequency was more intense far from big urban centers. Analyzing the spatial distribution of road kills, Cerdocyon thous and Tamandua tetradactyla showed defined peaks of road kill, in specific sites of the road, being also seasonally marked. There were no differences in the species richness between road stretches or between seasons. However, the number of road kills was higher in the stretch near the Pantanal biome, with emphasis on Carnivora and Pilosa. Overall, there were more road kills during the rainy season, with Cingulata as the main order. Management recommendations are done in order to diminish the road impact, such as the use of road sign in critical locations for road kills, use of fences for faunal contention in critical stretches, and facilitation of faunal movements for crossing safely the road.

El oso hormiguero, Myrmecophaga tridactyla: crecimiento e independización de una cría

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El oso hormiguero, Myrmecophaga tridactyla, es uno de los mamíferos más distintivos de la fauna neotropical, siendo una especie amenazada en algunas partes de su distribución. Sin embargo se conoce poco de la relación madre-cría, vínculo fundamental en la sobrevida de esta especie. En este trabajo estudiamos aspectos relacionados a la interacción entre una madre y su cría durante su primer año de vida, en condiciones de semi-cautiverio. Consideramos el crecimiento y desarrollo de la cría, su forma de amamantamiento y su frecuencia, cuidados de la madre a su cría (acicalamiento y transporte), expresiones de juego e independización de la cría. Ambos se encontraban en la Reserva Experimental Horco Molle en el noroeste argentino y tenían acceso a un predio de 20 hectáreas cercadas. Se realizaron más de 600 horas de observación, incluyendo filmaciones de video, desde el nacimiento de la cría hasta el año de edad. Los resultados muestran que la etapa comprendida entre el octavo y noveno mes de vida es crítica. Durante este período se observa que la cría deja de mamar, aumenta el consumo de alimento (acercándose a los niveles de consumo de la madre), la madre deja de transportar a su cría y deja de acicalarla, la madre deja de jugar con su cría aunque esta sigue jugando hasta el undécimo mes (observándose elementos característicos del juego locomotor, con objeto y social) y, finalmente, los niveles de exploración aumentan considerablemente en ambos. Tomados en su conjunto, estos factores indican que el corte aproximado del vínculo madre-cría se iniciaría en el octavo mes para completarse en el noveno. En condiciones naturales es probable que sería en esta época que la cría emprendería paulatinamente su vida solitaria.

The anteater, Myrmecophaga tridactyla: growth and independization of an infant. The anteater, Myrmecophaga tridactyla, is one of the most distinctive mammals of the Neotropical fauna, being a threatened species in some parts of its distribution. Yet, little is known of the relationship between mother and infant, a fundamental bond for the survival of this species. In this paper, we studied aspects related to the interaction between the mother and her infant during its first year of life in semi-captive conditions. We considered the growth and development of the infant, nursing method and frequency, care provided by the mother to her young (grooming and transportation), play behavior, and the independization of the infant. Both lived in the Reserva Experimental Horco Molle in northwestern Argentina and had access to a fenced 20-hectare terrain. We recorded more than 600 hours of observation, including videotaping, starting at the birth of the infant until one year of age. Results show that the period between the eighth and ninth month is critical. During this period, the infant stops nursing, increases food consumption (reaching consumption levels of the mother), the mother stops transporting her infant and stops grooming it, the mother stops playing with her young although it continues to play until its eleventh month (observing characteristic elements of locomotor, object and social play), and, finally, exploration levels increase considerably in both mother and infant. Taken together, these factors indicate that the approximate break in the mother-infant bond would begin during the eighth month to be completed by the ninth month. In natural conditions, it is possible that it would be at about this time that the infant would gradually start its solitary life.