Goose barnacle migrate, it was thought that barnacle geese, "Branta leucopsis", developed from this crustacean, since they were never seen to nest in temperate Europe, hence the English names "goose barnacle", "barnacle goose" and the scientific name "Lepas anserifera" (, "goose"). The confusion was prompted by the similarities in colour and shape. Because they were often found on driftwood, it was assumed that the barnacles were attached to branches before they fell in the water. The archdeacon of Brecon, Gerald of Wales, made this claim in his "Topographia Hiberniae". Since barnacle geese were thought to be "neither flesh, nor born of flesh",
Branta correctly assigned – meaning that the genus "Anser" was once much more widespread than today and that it coexisted with "Branta" in freshwater habitat which it today does only most rarely – is not clear. Especially in the case of "B. dickeyi" and "B. howardae", doubts have been expressed about its correct generic assignment. The former ""Branta" minuscula" is now placed with the prehistoric American shelducks, "Anabernicula". On the other hand, a goose fossil from the Early-Middle Pleistocene of El Salvador is highly similar to "Anser" and given its age and biogeography it is likely to belong to that genus