Drones blasting AC/DC and Scarlett Johannson are helping biologists protect cattle from wolves

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In this image taken from video released by the USDA, Gray wolves halt an attack on a cow at an undisclosed location along the Oregon/California border after a drone emits noises at them as part of efforts by the USDA to monitor predators at night and repel them from livestock by non-lethal means. (USDA via AP)