Only three species of bumble bees, Bombus terrestris (L.), B. ruderatus (Fab.), B. subterraneus subsp. latreillellus (Kirby), were thought to have become established but a recent survey shows that a fourth species, B. hortorum (L.) is present and wide-spread east of the main divide and south of Balcairn in north Canterbury. Distribution, life cycles, seasonal abundance of food and its influence on local abundance of species, tongue length and foraging behaviour in relation to relative efficiency of B. terrestris and B. ruderatus as pollinators of these two crops, are discussed. The efficiency of honey-bees and their future use in New Zealand as pollinators of red clover as well as further studies of bumble-bees in relation to this problem are considered.
Keywords: NZSAPAB;