An Agouti Eating Pulp of the Dipteryx panamanensis Seed Coat

Agoutis are rodents exclusive to forested and wooded lands of the American tropics. Their habitats include rainforests and savannas. Some species have even adapted to live in cultivated fields. They are active during daytime. At night they hide in hollow tree trunks or in burrows among roots.

Here in this short observation recorded at the Smithsonian Tropical Research Institute (STRI) in Barro Colorado Island, Panama you can see an agouti feeding on the outer pulp of the one of the major emergent canopy tree species in Panama locally known as “almond tree” (almendro) which is in fact a legume (Fabaceae). Agoutis are one of the most effective seed dispersers of Neotropical forests. Until recently most ecologists were considering them as seed predators like peccaries or monkeys who chew and destroy most of the seeds. Birds such as the iconic toucans were seen as the most effective seed dispersers. Many birds such as toucans play a special role for many trees since lacking teeth they digest and regurgitate many large seeded fruits far away from the mother tree. Therefore seeds dispersed by birds generally thought to have higher chance to germinate.

A study carried out on the black palm (Astrocaryum standleyanum) however painted a quite interesting picture about agouti seed dispersal by hoarding. Seeds tagged and tracked by miniature radio transmitters over a year have shown that agoutis steal seeds cached by their neighbors and more than a third of the seeds buried this way moved more than 100 m. One seed was buried 36 times before an agouti dug it up and ate it. About 14 percent of the seeds survived until the following year.

In the absence of seed dispersers many palm seeds that fall under the mother tree get attacked by bruchid beetles or fungi. When seeds are buried underground this gives them a better survival edge especially against beetle attack.

Surprisingly, agoutis can swim and even dive underwater very well and can colonize relatively isolated inundated locations in wet forests.