Giant anteaters (Myrmecophaga tridactyla) are native to Central and South America and are found in savanna ecosystems where there are mosaics of grasslands, forests and wetlands. They establish a home range that includes all of these types of habitats and roam within this range, seeking food.
Unusual among mammals, giant anteaters have a low capacity to produce body heat and need to find shelter when it is cold. Forest patches are critically important in this respect because they form thermal shelters where anteaters can keep warm and escape the worst effects of rain and wind.
Many mammal species change their behavior or movements in response to thermal variations; this phenomenon is known as behavioral thermoregulation.
In light of continuing deforestation, the researchers investigated the effects of forest cover on the movement ecology of 19 giant anteaters that had been fitted with GPS trackers. The study was conducted at Santa Barbara Ecological Station in São Paulo state and at Baía das Pedras Ranch in Mato Grosso do Sul state in Brazil.
When analyzing movement data from the GPS-tagged anteaters, the researchers took into account the sex and body size of each anteater, as well as the amount of forest cover available.
The results showed that male anteaters had larger home ranges than females with comparable body sizes, and tended to make more intensive use of the space. They explained this by saying that ranging across a larger area would possibly increase the chances that a male would encounter a female.
In areas that had less forest, however, both male and female anteaters made use of larger home ranges. This was seen as an adaptation to ensure the inclusion of forest fragments in their home ranges where they could take refuge from the cold and make use of behavioral thermoregulation.
The authors said their findings highlight the role of forests as an important thermal resource driving how much space giant anteaters need.
The experts also emphasized that forest management should focus on protecting forest fragments in areas where giant anteaters occur. This would enable the animals to make use of behavioral thermoregulation in the face of the more frequent and intense extreme weather events associated with global warming and climate change.
The study is published in the journal PLoS ONE.