Having paid our $10 to gain entrance to the park, we then also clubbed together (5 times $10 each) to pay for a guide to show us round on a 2 1/2 hour tour. We definitely swa more wildlife than if we hadn't have had a guide - he also carried a spotter scope which was worth it's weight in gold.
The highlight for me was seeing (and being able to photograph) this Laughing Falcon. We also saw a humming bird sat on its nest. Sadly though when we returned the following day the nest had gone - a sign of the effects of occasional irresponsible tourism.

We also saw lots of monkeys, though in reality they are so tame as to be a pest, as are the racoons.
After the walk, I took the opportunity to swim for an hour or so in the Pacific breakers before heading into town for some lunch. I then caught the bus back Quepos for a bit of shopping and a lazy late afternoon.