pollen limitation.

Mutualisms with the wreckage of an avifauna: the status of bird pollination and fruit-dispersal in New Zealand

Worldwide declines in bird numbers have recently renewed interest in how well bird–plant mutualisms are functioning. In New Zealand, it has been argued that bird pollination was relatively unimportant and bird pollination failure was unlikely to threaten any New Zealand plants, whereas dispersal mutualisms were widespread and in some cases potentially at risk because of reliance on a single large frugivore, the kereru (Hemiphaga novaeseelandiae). Work since 1989, however, has changed that assessment.