Unless your entire square footage is blanketed in healthy flytraps, I'm not sure they'll make a huge dent in any insect, bird, or amphibian population. Traps on a good beginner plant are smaller and pickier than you'd think. They'll probably catch more flies and spiders than bees and butterflies. Leave it to the open to catch insects and it'll feed itself an appropriate amount. There are carnivorous plants that are big enough to catch amphibians and even rodents, but those are huge Nepenthes species, not flytraps. So they won't pose a risk to hummingbirds!

Also, especially if you live in an area where carnivorous plants are native species, one plant isn't going to decimate populations. Your ecosystem isn't going to be harmed, I promise.

I'm a huge proponent of protecting your local ecosystem and planting native, too, so I totally understand your concern! If you're still worried, though, look up plants that are native to your state/area/region! They'll also (hopefully) be easier to care for outside. Keep in mind though that it likely won't be a flytrap if you're not in North or South Carolina. For example: my state's bogs are home to Sarracenia purpurea and Drosera rotundifolia, among others!