There is another answer to how the toxin gets on the bird’s feathers besides the birds eating the beetles. Many birds use insects to preen their feathers.

Ralph Gundersen
St. Cloud, Minn
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“Because we do find significant toxin levels in internal organs . . . we believe that [the birds] are ingesting at least some of the beetles,” says Jack Dumbacher of the California Academy of Sciences .—S. Milius