Macaroni penguins spend the winter at sea and return to colonies on land during the austral spring to reproduce. Arrival weights of male and female Macaroni penguins on Bird Island, South Georgia have been monitored since 1988. The current protocol is that 50 males are weighed on 28th October and 50 females on 8th November. This work was funded by Natural Environment Research Council (UK) core funding to the British Antarctic Survey.

The breeding success (calculated from nest and chick counts) of Macaroni penguins is monitored annually at Bird Island, South Georgia. A transect is used to estimate the incubating nests and chicks hatched in the large colony at Goldcrest Point where counts have been made since 1976. The number of incubating nests and chicks reaching fledging stage in the whole of the smaller colony at Fairy Point are counted and data exist from 1982 onwards. This work was funded by Natural Environment Research Council (UK) core funding to the British Antarctic Survey.