mits, nesting in rock crannies that provide shade and moisture. They can live on their fat through the winter, protected from freezing within the same shelters that shielded them from the summer's heat (4:74). In the spring they waken and mate before returning to the lowlands to lay their eggs--where they will resume feeding on aphids. A single ladybird may eat as many as five thousand aphids during its lifetime.
During the ladybirds' dormant period, they have often been picked up by the millions and offered for sale to farmers plagued by aphids. However, according to entomologist Kenneth Hagen, of the University of California at Berkeley's Division of Biological Control, hibernating ladybirds are useless for pest control. This is because the ladybirds' instinct is to disperse without even searching for food locally once their yearly cycle has been interrupted (4:74).
Hawaii is another example of where insects have been imported, however, not for pest control but because they were brought by tourists and cargo shipments. Ecologists estimate that a n
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