Vanhankaupunginlahti’s rarest regularly nesting bird is the citrine wagtail (Motacilla citreola) (pictured). This bird wetland is the citrine wagtail’s only regular nesting site in Finland. The citrine wagtail is an eastern species, which is slowly spreading to the west. It is quite similar to the western yellow wagtail (Motacilla flava), which also nests in the Vanhankaupunginlahti, as well as in meadows and bogs.
The male western yellow wagtail can be distinguished from the male citrine wagtail by the fact that the latter not only has a yellow belly, but a yellow head as well. For bird watchers, the arrival of the citrine wagtail in Vanhankaupunginlahti around May Day is one of the spring’s most notable occasions. In 2016, citrine wagtails nested by the area’s duckboard trail. At other times they’ve made their nests in the cow pasture on Lammassaari island.