Density, Abundance and Activity Patterns of the Endangered Tapirus Bairdii in One of its Last Strongholds in Southern Mexico

Abstract

Baird´s tapir (Tapirus bairdii) is one of the most emblematic mammalian species from Mesoamerica. Due to its level of evolutionary distinctiveness and anthropogenic threat this species was recently ranked in 34th position, in terms of its urgency for conservation, among more than 4,000 species of mammals assessed by experts from the Zoological Society of London. Despite its evolutionary and conservation relevance there remain important gaps in knowledge of the basic ecology of this species. Based on camera-trapping data, we estimated Baird´s tapir abundance and analyzed its patterns of daily activity and preference for different altitude intervals in El Triunfo Biosphere reserve, one of the last strongholds for this species in southern Mexico. We also applied a recently developed method (Random encounter model) to estimate tapir density without the need of individual identification. Tapir relative abundance was: 1.3 events/100 camera-trap days and density: 0.12 ind./km 2 . Tapir activity concentrated around dusk (χ 2 = 21.18, P<0.01) and use of mid-altitude areas was preferred (χ 2 = 49, P < 0.001). This study provides data on the ecology of the species and insights on study methods that can have a direct positive impact on its management and conservation.Keywords: density estimation, camera-trapping, cloud forest, mammal threat, daily activity Resumen El Tapir o Danta centroamericana (Tapirus bairdii) es una de las especies de mamífero más notables de Mesoamérica. Debido al grado de amenaza que experimenta y a que representa una línea evolutiva muy distintiva, esta especie fue recientemente colocada en el lugar 34, en términos de la prioridad de su conservación, entre más de 4,000 especies de mamíferos evaluados por expertos de la Sociedad Zoológica de Londres. A pesar de esto, persisten importantes vacíos en el conocimiento de la ecología básica de esta especie. Con base en un estudio de foto-trampeo estimamos la abundancia de T. bairdii y analizamos sus patrones de actividad, a lo largo del día, y de uso de sitios a lo largo de un gradiente altitudinal en la Reserva de la Biosfera de El Triunfo, uno de los últimos refugios de la especie en el sureste de México. Asimismo, aplicamos un método recientemente desarrollado (Modelo de encuentros aleatorios) para estimar la densidad del tapir sin la necesidad de realizar identificación individual. Los valores estimados de abundancia relativa de la especie y densidad fueron: 1.3 eventos/100 días cámara-trampa y 0.12 ind./km 2 . La actividad del tapir se concentró alrededor del anochecer (χ 2 =21.18, P<0.01) y en la zonas de altitud media (χ 2 = 49, P < 0.001). Este estudio presenta información sobre la ecología básica de la especie y sobre aspectos metodológicos de su estudio que pueden impactar de manera positiva las prácticas para su manejo y conservación.Palabras clave: estimación de densidad, foto-trampeo, bosque de neblina, mamíferos amenazados, actividad diaria.

Moon light and the activity patterns of Baird’s tapir in the Calakmul region, Southern México

“…Tapirella bairdii is a solitary animal that can exhibit both diurnal and nocturnal behavior, even though several studies showed that they tend to be more active at night and crepuscular periods (Carbajal-Borges et al 2014), probably because of the difficulty to dissipate the body heat, a situation that is common to all large animals (Randall et al 1998;Foerster and Vaughan 2002). According to this, Tapirella bairdii would avoid the hottest hours of the day and restrict their movements to the cool hours of the day (Padilla and Dowler 1994;Foerster and Vaughan 2002).…”

Using a novel model approach to assess the distribution and conservation status of the endangered Baird's tapir

“…Naranjo‐Piñera () estimated 0.6 individuals/km 2 in Corcovado National Park in Costa Rica using transects, while our model estimates a mean of 0.81 individuals/km 2 in the same protected area. Carbajal‐Borges, Godínez‐Gómez, and Mendoza () cite 0.12 individuals/km 2 as their estimate for tapir abundance in the core area of El Triunfo Biosphere Reserve (though the estimates range up to 0.49 using different assumptions), while our model estimates a mean of 0.40 individuals/km 2 across the core area of the reserve. Mejía‐Correa, Diaz‐Martinez, and Molina () estimate 1.02 individuals/km 2 in Los Katíos National Park of Colombia, while our model estimates a mean of 0.65 individuals/km 2 in the same protected area.…”

Monitoring program for mammals in a protected area of Colombia

“…Lizcano & Cavelier (2000) support this assertion; they indicate a movement of tapirs from paramo (a high Andean ecosystem) towards lower altitudes, stimulated by the development of farming and livestock grazing areas associated with human settlements. Carbajal-Borges et al (2014) confirmed the influence of anthropic intervention on the activity patterns of Baird's tapir (Tapirus bairdii). For them, this species showed mostly crepuscular activity and diurnal activity in areas providing the animals with a highly protected habitat.…”