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Feral pigeons bred in all months of the year but did less well in March when food was short. The most common clutch size, two, was also the most productive, 50% of eggs producing flying young. Clutches of one and four had significantly lower productivity. Clutches of one accounted for 15% of total clutches, three for 1% and four for 3%. Man seemed to be the only important predator of adult birds.

During 1965, 1406 sea birds and during 1966, 1102 sea birds were recovered from 1064 km and 785 km of New Zealand beaches. Monthly recovery rates indicated that sea bird mortality was usually higher in spring and summer (September to February) than in autumn and winter (March to August). Two wrecks were recorded during the two-year period, both on Wellington west coast beaches, and following periods of westerly or south-westerly winds. From September to December 1965 species affected included fairy prion, sooty shearwater, short-tailed shearwater, fluttering shearwater and diving petrel. In July 1966 there was a wreck of lesser broadbilled prions. Uncommon species found were blue petrel, Fiordland crested penguin, Pycroft’s petrel and Antarctic fulmar (all in 1965), and Arctic skua (in 1966).

Petrels, especially Procellariidae and Hydrobatidae, visit their breeding places in lesser numbers on moonlit nights than on darker nights. This is probably caused by poor feeding conditions because prey do not come so near the surface on moonlit nights. Fledgling petrels, mainly Procellariidae, are particularly liable to be attracted to artificial lights situated near the breeding colony. It is suggested that nocturnal-feeding petrels are instinctively attracted to light sources because they exploit bioluminescent prey. A small proportion of fledglings seem to be initially misled by this instinct.