Black Shag

Maori Name: Kawau

Phalocrocorax carbo

 Maori name Kawau                                               

Also known as the Great Cormorant, or Black Cormorant, this native bird is widespread and moderately common.  There are at least three subspecies – novaehollandiae breeds throughout Australia, New Guinea and NZ.  Shags are medium to large long-necked birds that feed by diving from the water surface to catch fish and crustacean with their long hooked bill.

The Black Shag breeds at any time of the year given sufficient food and shelter, and make their nests, as a large platform up to 10m above water from sticks, twigs, plants and debris.  Nesting colonies are commonly in willows, pines, pohutukawa or beech trees overhanging water, cliff ledges in river gorges, coastal cliffs or in low scrub on offshore stacks.  Occasionally they will nest on the ground, or in trees well away from water.  Most eggs are laid June-October, 2-3-5 eggs, 2 days apart with an incubation period of 27-31 days.  Chicks are fledged at around 7 weeks old and continue to be fed by their parents for a further 7-10 weeks.

Both sexes are alike - black with a white patch on cheeks, yellow facial skin which in the breeding season becomes orange-red.  The breeding adult also has a white thigh patch, a small black crest on neck and filoplumes (thread-like feathers). The bill is grey, the eye green and the feet black.

The black shag is found throughout NZ in muddy estuaries, tidal areas and sand banks but also inland along drains, canals, and lakes in most freshwater localities.

Considered a pest by fishermen in the past, they were given partial protection in 1986 after it was shown that they eat young eels, and so are of some benefit to game fishers.  They are often caught in fishing nets and occasionally on hooked lines.