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Daily activity pattern of reintroduced giant anteaters (Myrmecophaga tridactyla): effects of seasonality and experience

  • Yamil E. Di Blanco ORCID logo EMAIL logo , Karina L. Spørring and Mario S. Di Bitetti
From the journal Mammalia


We assessed the effect of seasonality and intrinsic conditions on daily activity pattern of giant anteaters reintroduced in the Iberá Reserve, Argentina. During 2007–2012 we gathered 159 24-h focal samples on 15 radio-marked individuals (11 captive-reared, four wild-reared; seven adults, eight juveniles), 216 records of beginning and end of activity bouts on 20 individuals, and 454 camera-traps records (3345 trap-days). We estimated the daily hours of activity, the percentage of diurnal and nocturnal activity, and the daily activity range and time overlap using time as a circular variable in kernel density estimations. We assessed differences between seasons, sexes, age classes, and types of rearing. The average daily hours of activity was 8:43 h. Camera-traps and radio-telemetry showed similar results. Animals exhibited both diurnal (60–65%) and nocturnal (40–35%) activity. The higher probability for being active ranged within 09:00–03:00 h. Anteaters spent more hours active and were more nocturnal during summer. Activity was highly overlapped between sexes, and wild-reared individuals were more nocturnal than captive-reared ones. Seasonal shifts in daily activity highlights the importance of thermoregulation as a selective factor in this species. The giant anteater is a cathemeral species with flexibility to accommodate its activity pattern to local conditions or experience.

Corresponding author: Yamil E. Di Blanco, Instituto de Biología Subtropical, sede Puerto Iguazú, Universidad Nacional de Misiones (UNaM) – Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Asociación Civil Centro de Investigaciones del Bosque Atlántico (CeIBA), Bertoni 85, Puerto Iguazú (CPA N3370BFA), Misiones, Argentina, e-mail: .


This study was funded by The Conservation Land Trust and was developed under formal agreement with the Government of Corrientes province and Argentina. YDB conducted this research with a doctoral scholarship from CONICET. We thank Constanza Pasian, Chele Martínez, Pablo Díaz, Imanol Cabaña, Talía Zamboni, Viviana Tartarini, María Ángeles Párraga Aguado, Gigi Welter and Valeria Androsiuk whom assisted in data gathering. Gustavo Solís, Marcela Orozco, Javier Fernández, Federico Pontón, Rut Pernigotti, Sebastián Cirignoli and Alicia Delgado helped with anteaters rescue and management. Ignacio Jiménez Pérez, Sofía Heinonen and the CLT staff helped with logistics and administrative issues. Carlos Zucco helped with data analysis. We would also like to thank Marcus Clauss and an anonymous reviewer for valuable comments on the original manuscript.


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Received: 2015-5-26
Accepted: 2015-12-15
Published Online: 2016-2-24
Published in Print: 2017-1-1

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