Our guide, Scott, told us that when monkeys are near, all birding comes to a standstill.

This is even more true when these monkeys happen to be capuchins.

We were taking a morning walk through the coastal, lowland rainforest of Parque Nacional Carara. We had great views of a royal flycatcher, seen two circling short-tailed hawks through the trees, and stood on the trail under a mixed feeding flock as they passed over us.

We took a side trail in search of other mixed feeding flocks and were soon alerted to a loud crashing of leaves and branches that signaled that a large animal or animals were very near. Which-necked capuchin monkeys!

It was impossible to ignore these energetic primates that made the howler monkeys that we had seen at La Selva look like lethargic sloths by comparison. The troop of 10 to 15 monkeys moved up, down, and around the canopy as we earthbound mammals craned our necks to follow their frenetic progress.

It is no wonder why primates and these new world monkeys, fascinate us. When you look into the face of a capuchin, it’s like looking into the face of a long, lost cousin. Albeit one with a long, prehensile tail.

These monkeys also share another trait with Homo sapiens: they also use tools. In Manual Antonio National Park (just down the coast from Carara) a capuchin was observed beating a fer-de-lance (a viper responsible for many human death each year) to death with a stick. Well done!

Capuchins in the canopy of Carara National Park, on the Pacific slope of Costa Rica.