My birding experience + how I feel about this movie...
First, I have to say that I'm not a birding enthusiast at all, but this movie brought back memories. I had to take an ornithology class in college, and the professor was a hardcore birding enthusiast. He once spent three weeks on the mountains looking for a rare bird. He took his fiancé to central America in a birding trip. There was an earthquake and instead of grabbing the fiancé and running out of the house, he grabbed his birding list. He would make us show up at 5 am to class to go birding. We also had to go on over-night birding trips every other weekend, and we had to memorize entire CDs of bird calls. Worst class I took in college. After that, I was so tired of birds that I didn't eat chicken for six months.
So, while I was watching the movie, I kept thinking that Hollywood usually exaggerates but not in this instance. Some birding enthusiasts do go to extremes. The weird thing is that 10 years later, every time I see a bird, I want to identify it. That class left me traumatized.