. . . . . . . . . "Branta bernicla" . . "Ulva" . . "Duarte Frade. 2017. Branta bernicla feeding on Ulva. iNaturalist.org. Accessed at <https://www.inaturalist.org/observations/8598993> on 05 Apr 2018." . . . . "http://iNaturalist.org is a place where you can record what you see in nature, meet other nature lovers, and learn about the natural world." .