Interactions between native and introduced bees in New Zealand

There are about 40 species of native bees in New Zealand, 36 of which belong to the Colletidae family, and the rest to the Halictidae. Introduced species include Apis mellifera, 4 Bombus species, and Nomia melanderi and Megachile rotundata. Honeybees in commercial apiaries, and other introduced species, forage mainly on introduced plants, but some honeybees do compete with native bees on native plants. The Peak of foraging by native bees occurs at the season of the main honey flow, when there is most food. It is thought that competition for nest sites does not occur. It is concluded that the introduced species do not have a deleterious effect on native species; much more information on the latter is needed. P. Walker