Dogs rarely freeze at light... They BOLT!!!! He will grab the chicken, tug and as the insulator comes out of the switch, the dog will hear the arc of the 12 volts contacting and he will have the after burners on right then... WINNER WINNER CHICKEN DINNER!!!
Is this a remote location? The farm? Electricity available? If you have electricity, I can come up with a half dozen "legal" "yard light" options that will illuminate the dogs without spooking them so quick. If remote, that number is limited somewhat.
Brent