Illuminations: Northwestern Crows

Sea gulls and crows feed on various types of mollusks by lifting them into the air and dropping them onto a rock to break open their shells.

Biologists have observed that northwestern crows consistently drop a type of mollusk called a whelk from a mean height of about 5 meters. The crows appear to be selective; they pick up only large-sized whelks. They are also persistent. For instance, one crow was observed to drop a single whelk 20 times. Scientists have suggested that this behavior is an example of decision-making in optimal foraging.


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Biology, Zoology
Data, Graphing & Statistics
Birds, Mollusks, Seabirds
High School, Educator

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Illuminations (National Council of Teachers of Mathematics)

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