77-94 cm, sexes similar. Like pelicans and boobies, they have the 4 fingers joined by a membrane to facilitate swimming. The species is present throughout the year, increasing dramatically during migration and wintering. For foraging, it frequents a wide range of aquatic habitats, from the open sea to the network of drainage canals. Since 2008, it has nested in a single colony situated in a grove of a lagoon island. It forms large dormitories in lagoon thickets and riparian forests. As it feeds on fish, it is feared by the operators of the valli di pesca (fishing reserves) because of its predation of farmed fish.