The Arenal volcano is supposed to be active, although not to the point that there is lava flowing or explosions. What we saw is a lot of cloud activity around it! But on two occasions, the summit was clear enough that we saw the shape of it, and we distinguished two sources of fumes, like thin streams of clouds, except they were going in opposite direction from the clouds.
We're staying at the Arenal Observatory Lodge. From the deck that faces the volcano, we tower above a lovely garden, that many animals inhabit. Mostly birds --including hummingbirds, toucans and oropendolas--, but also a coati or two and a couple of great curassows.
Yesterday we walked on a few of the trails around the lodge, reaching a river with old lava, a hanging bridge, a waterfall.
Today we went to the Arenal Hanging Bridges, a park of 600 acres of rainforest with 6 hanging bridges and numerous regular bridges, a trail of 3 kilometers (1.8 miles) that we "achieved" in slightly over 4 hours (possibly a world record of unspeed).
We saw a blue ara in the parking area. It flew noisily above us and landed close to us. Then it posed on top of a fence and even let us stand quite close.
Inside the park we saw lizards, ants, a few birds, two black squirrels, insects (not a lot, thankfully, there was one, somewhere between the ant and the wasp, that was as big as a little bird. Eek).
On the way back we stopped next to a field where cows were grazing. Or rather a breed of cows. They looked like zebus with ears like those of donkeys. Their head was very much like that of Jar-Jar Binks, in fact.