Zevachim 7:2-3

Zevachim 7:2

If the kohein offered a bird burnt offering above the red line (where it belongs), in the manner of a burnt offering and under the name of a burnt offering, it is valid; in the manner of a burnt offering but under the name of a sin offering, it is valid but the owners do not fulfill their obligation with it; in the manner of a sin offering but under the name of a burnt offering, or in the manner of a sin offering and under the name of a sin offering, it is invalid. If he offered it below the line in any of these ways, it is invalid.

Zevachim 7:3

None of the bird sacrifices that were performed improperly (as detailed in the past few mishnayos) render one ritually unclean by swallowing them (even though they are unfit to eat), and they are subject to the laws of misappropriation except for a bird sin offering that was offered below the line in the manner of a sin offering and under the name of a sin offering (which is fit to be eaten and therefore belongs to the kohanim rather than to the Temple).