How Do Deer Use Their Sense of Smell?

He immediately dived into impenetrable South Carolina cover. However, because the idea that I might miss was absurd, I waited ten minutes and then walked over to where he had been standing. There was blood all over the place, but the plantation rules stated that thou shalt not track deer on thine own, so I got back on the stand and waited for the truck to come around.

This took about an hour, and while waiting for it, I saw a doe walk right into the grass patch, right where the blood and my bootprints were, and commence browsing without a care in the world. She filled her face for 10 minutes or so and then ambled off.

This is not the first time I've seen such a thing happen. And I wonder, exactly what part does scent play in the mental makeup of these critters? Anyone out there have any similar experiences?