Hotel Aguila de Osa in Drake Bay, Costa Rica was one of my favorite in the country at the end of my 6 days - 5 nights there in May 2017. At the time the facilities were about 23 years old but well maintained and they provided some of the best services and food I have found in Costa Rica. It is not a "birding lodge" and was not one of my best birding spots, but was good for that too along with other animals. The tours and activities offered are quite broad with lots to do for a full week easily!
I, like most guests, was busy with multiple activities during the day. If you are one who likes to lay around the hotel during the day, you will be disappointed that it is not air-conditioned in such a hot, humid, rainforest on the coast. But at night the ceiling fan was more than adequate and I even turned it off twice and used the blanket.
Be aware that you cannot drive a car to this hotel. You get to it by boat or by walking the Drake Bay Trail. I flew to the little Drake Bay airport where a taxi took me to the village of Drake Bay and their beach. I waded through the surf to an Aguila boat that took me and my luggage to the hotel where I was royally welcomed with a free cocktail, activities guidance, and introduction to my room. Also be aware that your room is uphill from the dining room, like three flights of stairs. That would be hard for some people.
But if you are wanting multiple experiences in nature with fabulous gourmet food and terrific service at every level, then this is a place for you. Check out their website at :
http://www.aguiladeosa.com/ Hotel Website