Spent a couple of weeks in Costa Rica this summer. We were there in July, the "official" start of the rainy season. Apparently most tourists come there after the rainy season is over (Nov-Dec) so we saw relatively few tourists.
We did see a few rain showers but nothing too bad. Keep a raincoat with you at all times or an umbrella. Hurricanes do not typically make landfall there.,. Maybe once in 7-10 years.
Costa Rica is incredibly beautiful once you get out of the cities. Plan a trip to Monteverde if you want to get photos of birds. They have a huge variety of them, not just hummers. You should be able to see toucans and parrots and macaws and if you are super lucky maybe even a quetzal.
Another place we visited was Volcan Miravalles and stayed at a place called Colinas de Miravalles. This place is off the grid since apparently it not on any tourist map. we were there for three days and the only people we rubbed shoulders with were the locals. Here as well there were a lot of different birds.
Tamarindo is a beach town. And if you do go there you should get some incredible shots of pelicans. Walk on the beach in the mornings and they will be fishing there a few meters off the shore.
Another place to visit would be the Tortuguero National park. Most of the park is water, so the "safari" tours are on kayaks and motor boats. And the forests are there are packed with toucans, anhingas, flamingoes, jacanas.
All the best planning the trip. I'm sure you'll have a wonderful time there.
CC always welcome.