TIL that the ruby-throated hummingbird flies non-stop across the Gulf of Mexico as part of its spring migration and has a VO2 max that is about 10 times higher than elite human athletes.
This feat is impressive, as an 800 km (500 mi), non-stop flight over water would seemingly require a caloric energy that far exceeds an adult hummingbird's body weight of 3 g (0.11 oz). However, researchers discovered the tiny birds can double their fat mass in preparation for their Gulf crossing, then expend the entire calorie reserve from fat during the 20-hour non-stop crossing when food and water are unavailable.
I've heard similarly. I guess you're just going to have to introduce yourself and get all their names. But don't tell them they all look the same. Birds find that offensive. 🙃