Wildlife biologists turn to solar-powered ear tags
Idaho Fish and Game Department researchers are planning to study Mule deer bucks during the 2019 hunting season, and they’ve enlisted a new tool to help.
This year, biologists will attach solar-powered ear tags that will allow them to track deer movements without worrying about drawing down a battery. They’re expected to last four to five years.
This winter, they deployed 20 solar-powered, GPS ear tags to bucks in three different hunting areas. During the hunting season, the tags will record and save the locations of tagged bucks every 30 minutes, then transmit the data the next time the device is near cellular service.
Researchers are hoping to learn how hunting seasons affect the movement of bucks and how wildlife managers influence mortality with the hunting season.
Bucks have been hard to track in the past because the collars researchers used had some inherent challenges. When male fawns turn about a year old the circumference of a buck’s neck can vary dramatically. During a rut, for example, the circumference can increase up to 50% before shrinking back to normal. As a result, it is difficult to keep a collar on a buck.
The ear tags address the problem of swelling necks. Because they are solar-charged, the can be affixed when a buck is young and allow researchers to continue to monitor them throughout their lives.
Like collars, the devices will send out mortality signals if the animal hasn’t moved for some time. Researchers will rely on hunters to return some ear tags after they’ve harvested bucks during the hunting season.
