The first bird Noah sent from the Ark after the waters receded was a raven.
Genesis 8:7 says Noah sent out a raven after the Ark came to rest. The raven flew back and forth until the waters had dried from the earth. Noah then sent a dove to determine whether the floodwaters had subsided.
The dove is much more famous because it later returned with a freshly plucked olive leaf, a sign that the land was becoming habitable. That memorable image often causes people to remember the dove as the first bird, but the sequence in Genesis places the raven first.
This question differs from asking which bird returned with an olive leaf. The answer to that later event is the dove; the first bird released was the raven.