This explains why when we let the dogs out the other night three noses went into the air all at the same time. Often we do not see the bears but the dogs know they are around. It was dark out and they smelled the bear. Three heads all turned and looked in the same direction at exactly the same time. Sometimes the bear will get curious and wander up to the house to check things out but mostly we just see signs of them. If it is dark outside we have three very excellent bear detectors. They are flawless.