I think this is my favorite species at zoomat. Chiapas is part of their natural range and at zoomat they are have a large outdoor exhibit. Every time i have gone to zoomat they are very active, though more in the mornings. In the U.S. and Europe tamanduas seem to end up always indoors all year, maybe it contributes to their daytime inactivity, though the southern species of tamandua may have other habit patterns of course.
@Carlos, also in indoor holdings I have seen very active tamanduas in Europe, eg in Antwerp and Amsterdam. I do not know why they mainly end up indoors (apart from their size), but there are also some zoos with outdoor enclosures such as Dortmund & Magdeburg. I do not know of being indoor all the time makes them less active, but it would probably at least be healthier to have also access to an outdoor enclosure...
