This list of birds of Maryland includes species credibly documented in the U.S. state of Maryland and accepted by the Maryland / District of Columbia Records Committee (MRC) of the Maryland Ornithological Society as of 2022. There are 456 species included in the official list. Eight additional species of questionable origin and two of exotic origin per the MRC are also included in this page. Of the 460 species, 121 are rare anywhere in the state, 64 are rare in some part of the state, six have been introduced to North America, two are extinct, and two have been extirpated. This list is presented in the taxonomic sequence of the Check-list of North and Middle American Birds, 7th edition through the 62nd Supplement, published by the American Ornithological Society (AOS). Common and scientific names are also those of the Check-list, except that the common names of families are from the Clements taxonomy because the AOS list does not include them. Unless otherwise noted, all species listed below are considered to occur regularly in Maryland as permanent residents, summer or winter visitors, or migrants. The following tags are used to annotate some species: (R) Rare - "Reviewable if found anywhere in Maryland" per the MRC (R*) Rare (limited area) - "Reviewable if found in certain specified ranges in Maryland" per the MRC (QO) Questionable origin - "Accepted species that may or may not be wild or naturally occurring" per the MRC (EO) Exotic origin - "Accepted species whose natural history precludes wild or natural occurrence" per the MRC (I) Introduced - a species that has been introduced to North America by the actions of humans, either directly or indirectly (Xt) Extinct - a recent species that no longer exists (Xp) Extirpated wild - a natural or wild species which is no longer found in Maryland, but still exists elsewhere (Xx) Extirpated exotic - a formerly established introduced species which no longer occurs in Maryland Ducks, geese, and waterfowl Order: AnseriformesFamily: Anatidae The family Anatidae includes the ducks and most duck-like waterfowl, such as geese and swans. These birds are adapted to an aquatic existence with webbed feet, bills that are flattened to a greater or lesser extent, and feathers that are excellent at shedding water due to special oils. Forty-six confirmed species, two of questionable origin, and one of exotic origin have been recorded in Maryland. Black-bellied whistling-duck, Dendrocygna autumnalis (R)