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The distribution and abundance of seabirds in eastern Cook Strait during autumn is described. Notes on identification and behaviour are also included. Three coastal currents of mixed subtropical and sub-antarctic origin intermingle in eastern Cook Strait. Seabird assemblages of this region are dominated in autumn by large numbers of non-breeding migratory shearwaters from northern New Zealand. These birds leave in early May and are replaced by subantarctic species. White-capped mollymawks, SaIvin’s mollymawks and giant petrels are numerous in early autumn prior to their dispersal into the eastern boundary currents. The seasonal variability of food for offal-feeding petrels is much less than for species which feed solely on pelagic organisms. This explains the rarity with which flesh-footed shearwaters, Cape pigeons, Westland black petrels and albatrosses are cast ashore, and limits the value of storm-killed records as indices of petrel abundance.

It is estimated that a takahe requires about 300 K cal metabolizable energy daily for maintenance and that a bird feeding exclusively on grass will excrete about eight metres of faeces a day.

Breeding and post-breeding counts of takahe (Notornis mantelli) were made during 1972-73 and 1973-74 in three study areas within the Murchison Mountains: Takahe Valley and Point Burn, Eyles-Wisely, and Miller Peak. The Takahe Valley and Point Burn population declined markedly between 1966-67 and 1968-69 but only slightly between 1969-70 and 1973-74. Indications are that the Eyles-Wisely and Miller Peak populations may have declined only slightly since 1966 and actually increased in the present surveys. The decline in Takahe Valley and Point Burn is possibly related to suboptimum habitat.