That is not the kind of collar anyone wold put on a pet. It clearly has a pod under the deer's head which I suspect it is a GPS transmitting pod for research on deer movement. They can be on a heavy nylon collar or a leather collar . I have seen them before, and I lean towards the GPS collar instead of the telemetry collar. Just because most hunters have never seen a collared deer doesn't mean they aren't out there. I did some googling for GPS pods fr research collars and I found this. The shape looks the same as in the picture. Be aware, different companies make different configurations of the collars and pods.
http://www.telemetrysolutions.com/tr...ailed-deer.php