Phalacrocoracidae is a bird family that is under representation by about 40 species of the shags and cormorants. Of late there has been a different classification of this family, which has been recently proposed, while the number of their genera is still under incessant dispute.

The shags and cormorants differ in sizes, from medium sized to large seabirds. These birds are uniquely coastal as compared to being oceanic birds, while some have now colonized some inland waters. In fact, the cormorant ancestor seems to have largely been bird within fresh waters, if the habitat of the current lineage is anything to go by. These birds range across the globe, except for the area around pacific islands.

Geographical Distribution

The cormorants are largely distributed across most of areas of the world, where many of their species do range from the outskirts of boreal zones within the tropics, the only area without these birds being the Pacific islands only. For the Anhingas, their occurrence is rather widely seen within the tropic and subtropics areas. These in a nutshell means that they are worldly widely distributed in very suitable habitats within tropical zones, temperate and the boreal.

Habitat

The Phalacrocoracidae habitat is within the freshwater ponds, rivers, estuaries and lakes as well as in marine waters in coastal regions.

Behavior

The northern species of these cormorants are largely migratory, where they breed in more northern parts within their current range as well as going for winter to the southern part. The northern Anhingas populations are also intensely migratory. The anhinga and the cormorant have a quality of being gregarious, where they usually occur in a flock as they breed in one large colony. The cormorants do fly directly somewhat, mostly closely by the water surface using steady strong wing-beats. After they have swam, the anhingas and cormorants end up sitting on perches that are exposed with their wings largely spread before the sun for their plumage to dry. It lacks in oily repellants, where it ends up getting soaked wet while being immersed. In retrospect, these two Phalacrocoracidae birds are very strong swimmers, which allow them to pursue prey for food below the water surface, using both their feet for amicable propulsion.

Feeding and Ecology

The cormorants as well as the anhingas consume fish mostly, while their diet might also include frogs, squid and crustaceans. Their prey-catching maneuvers are characterized by a very agile movement with a swift underwater pursuit. For the cormorants, they catch prey with their bills while spearing the prey is the specialty of anhingas.

Reproduction

The Phalacrocoracidae birds, the anhingas and cormorants breed in colonies mainly. Their nests are awkward and usually built on trees or along cliff-ledges using sticks. The cormorant nests could be very messy sometimes, usually littered with fish remains, seaweed and other kinds of debris. They both lay about 2 to 4 eggs, which are elongated and rather chalky-surfaced, with a pale blue or green. Both parents share the egg incubation for about 23 to days as they do the same in rearing.