Recoveries by hunters of 842 black swans banded at Lake Whangape, North Island, New Zealand,between 1962 and 1975 were mainly confined to the Waikato and Northland districts, 88% being recovered within a 30-mile (50 km) radius of the lake. Five were recovered from South Island. At Lake Ellesmere, South Island, a cyclonic storm in April 1968 which altered the lake's ecology caused a change in the swans' dispersion. During 1956-68 and 1969-75 respectively, hunters returned 3950 and 745 bands, 83 and 78% of which were from within 10 miles (16km) of the lake. Of the more distant recoveries, 72 and 73 % were from the south-east of South Island. Most of the swans recovered from North Island were 2-year-olds. In 1969-75 more first and second-year birds and fewer older birds were shot on Lake Ellesmere than during 1956 and 1968. This difference is considered the result of a shorter game season and poorer food supply at the lake in 1969-75.