Maori name: Karuhinuhi
Length: 75-85 cm
Distribution: Around all New Zealand coasts. Also Australia. Occasionally inland waters.
Food: Fish and a few crustaceans.
Voice: Loud raucous calls described as screeching, gargling or barking.
Breeding: Colonial in trees which die after a few years. Two to four white eggs incubated by both adults for a month. Chicks fledge between 50 and 60 days. First breeding two to four years. Pair for life.
The Pied Shag is a common marine bird found around all New Zealand coasts and many off-shore islands although a few may be seen inland on larger lakes and rivers. They may be confused with the pied form of the Little Shag, but the latter is smaller (55-65 cm) and has a shorter yellowish bill. Pied Shags are also similar to the King and Stewart Island Shags. The King Shag is found only in Marlborough Sounds and like the Stewart Island Shag has a black face and a white mark on each wing.
Young Pied Shags have dark brown upperparts and streaked white and dark grey underparts.
Pied Shags are the common shags of the northern coasts of the North Island nesting in many trees especially Pohutukawas. They are more thinly distributed in the South Island.
Fish such as flounder and mullet are the main diet, but crustaceans are also taken. Fish are pursued underwater, the shag swimming rapidly, propelled by its webbed feet. Like other shags it needs to spread its wings to dry after a time of fishing.
Pied Shags nest colonially usually in trees or bushes. Occasionally Little Shags, Little Black Shags or Black Shags are found in the same colony. Nests are built of sticks and twigs usually brought by the male and presented to the female. Nearby nests are sometimes robbed for material. Nests may be used year after year, and as breeding occurs year round there is always some activity in the colony trees. These gradually die as they become covered with excrement or have the leaves plucked for nest material. Eventually the colony shifts to a new tree.
There are two peaks for breeding, spring and autumn but occupied nests have been found in all months of the year. Three or four chalky white eggs are laid at two day intervals. Both parents incubate the eggs, changing over at least three times a day. Hatching occurs between 25 and 33 days. Chicks are born naked. After a month they start moving in the vicinity of the nest perching on nearby branches. They fledge between 50 and 60 days and are cared for by parents for up to another 80 days.
Young may first breed at two years of age and once a pair bond is formed it is maintained from year to year.