You see a baby bird on the ground. It's so tempting to take the cute fluff-ball home and try to care for it. But not only is this likely to kill the young bird, it is also most likely illegal.
First off, the bird probably isn't abandoned. Birds fall out of their nests all the time when they're hopping around and learning to fly. This is part of their normal life. In fact, some birds are simply too big to remain in the nest even though they can't fly yet - so they do the rest of their learning process on the ground. The parents hang out nearby, bringing it food and helping it learn to fly. If something dangerous (i.e. you) comes along, they hide, hoping the dangerous creature will not spot the baby and will leave. They deliberately stay hidden.
Also, parents of course have to roam around and forage for food to feed their babies. So the babies fend for themselves for numerous hours each day.
The old wives tale that human scent scares off a parent has been proven not to be true. Parent birds don't care what their babies smell like, they take care of them. So if you see the nest around, you can always put the baby back into the nest. If not, leave the baby where it is or, if it's somewhere dangerous, tuck it into a safe nook. The parents will be back along to find it.
If it's a situation where the parents are CLEARLY dead, or the baby seems injured, then call your nearest animal rescue organization. Baby and growing birds have complex nutritional needs, and the likelihood of you raising the bird without severe nutritional deficiencies is slim. Injured birds can easily have far more harm caused to them by being picked up than the original injury caused. Trained animal handlers will know how to handle the bird without causing it further injury. The animal shelter will have appropriate food and also appropriate 'flock-mates' for the young bird, so it can grow up well adjusted and healthy.
Just about every wild bird in the US is illegal to keep as a pet or to care for in your home. From the CT State Wildlife Site: "It is illegal to keep wild animals as pets and raising wildlife for return to the environment requires considerable knowledge of appropriate feeding formulas, hours of care and sufficient facilities in addition to state and federal permits."
The Colorado state site also says: "If you are tempted to keep a baby bird: DON'T! Migratory birds, including songbirds, are protected under federal law. Possession of a bird, its nest or eggs without a permit is illegal. It is illegal to attempt to rehabilitate injured or orphaned wildlife without proper state and federal permits."
So the basic information is DON'T TAKE THE BIRD HOME. Watch it for enough hours that you are *positive beyond all doubt* that this bird really has no parents. And then contact someone who is trained and legally permitted to raise the bird.
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Collecting Nests and Eggs is Illegal
Tradition of the Easter Egg
Bird Nest Paintings and Artwork