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Breeding of pied shags (Phalacrocorax varius) at 2 colonies at Makara Beach, Wellington, was studied from Mar 1996, when breeding was 1st noted there, to May 2005. Pairs occupied and refurbished vacant nests rather than build new nests. The number of breeding attempts increased from 3 in 1996 to 46 in 2004, with 166 occurring during the study. New nests (n = 14) took about 3 weeks to build; most nests were used twice a year. Clutches were laid in all months, but there were 2 peaks: 61 nests (37%) in Feb–Mar and 53 nests (32%) in Aug–Sep. Overall, 76.6% were successful (fledged at least 1 nestling, n = 154 breeding attempts for which the outcomes were known), and the mean success was 1.4 fledglings nest^-1. The proportion of successful breeding attempts and the mean number of fledglings produced nest^-1 were similar for 1996-2000 (when the number of breeding attempts yr^-1 increased from 3 to 11) compared with the 2001-2005 period (when breeding attempts increased from 15 to 46 yr^-1). Of 14 breeding attempts for which clutch size was determined, mean clutch size was 3.4 (range 2-4 eggs), and mean brood size at fledging was 2.1 young (62% of eggs resulted in fledglings). The maximum number of shags counted at the colonies increased from 14 in 1996 to 68 in Dec 2003, after which numbers appeared to stabilize. However, since 2003, numbers of pied shags seen elsewhere in the Wellington region, particularly on Mana I and at Waikanae Estuary, have increased.