Data for monitoring the annual production of New Zealand sea lion were obtained by estimating the number of pups born in each year. These estimates were derived from direct counts of live and dead pups carried out at the sea lion colonies towards the end of the breeding season. The counts were performed when pupping was complete, but before the pups began to disperse. At the larger sites, a mark-recapture methodology was also used to obtain an estimate of the number of sea lion pups. The methodology used for the pup production estimates, and the rational for these methods, is described in Chilvers (2010).
The data presented here were obtained from a spreadsheet provided by the Department of Conservation, and by extracting the results from research reports. Where avalailable, individual counts made within each season are provided.