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We report Giant Hummingbirds (Patagona gigas), regularly and deliberately, ingesting wood ashes and slaked lime in central Chile. These two minerals have high concentrations of calcium, which may be a scarce element in the nectar-based diet of the species. Both observations occurred during the post-breeding period suggesting the birds were females ingesting calcium-rich compounds to replace minerals lost during eggshell production.
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Estades et al. (2008) studied this question.
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