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Breeding of North Island robins was monitored at two sites in Pureora Forest Park, central North Island, during the 19961 97 and 1997/98 breeding seasons. A total of 146 nests was found. First clutches were laid in September-October (mean: 20 September) and last clutches in November-January (mean: 17 December). Pairs had time to rear three broods during the breeding season (September-March), although most reared only two. Nest materials and nest location are described: mean nest height was 5.3 m (range 1.0 – 13.6). Mean clutch size was 2.60 (clutches of 2 or 3). Monthly mean clutch size increased from September to November, then decreased. The breeding biology of the North Island subspecies of robin at Pureora was similar to that of the South Island robin at Kaikoura. Nesting success improved dramatically after brushtail possums were poisoned by aerially distributed 1080 (sodium monofluoroacetate) baits, because mammalian predators were also poisoned. Robins are easy to monitor, and predation is a common cause of nest failure, so the species is potentially a valuable indicator of predator activity.