RFID chips already exist with that range (10-30') but they have to have on-board power - very thin batteries. You need two of them per hive body because of the geometry of the detection. (Briefly, the rated detection range assumes you are looking at the RFID chip face-on. The range when you are looking edge-on is nearly zero. Your range at an angle can be approximated by the cosine of that angle. Since we use rectangular boxes, you'd need tags in each of two perpendicular sides to ensure that one of them will always be facing you.) They're coming down a lot in price but two ultra-long-range active RFIDs are still in the $10-a-box range from what I can tell. And you'd have to replace them every few years as the batteries give out.

GPS trackers are the competing technology. Generally, a price of an order of magnitude higher still and even greater battery-life problems but you'd only need one per box and the range becomes basically infinite (as long as you stay on this planet).

There are some interesting hybrid technologies that combine GPS and Bluetooth at about $25 a box. They are currently being marketed as child-trackers but I think they have a lot of potential for other uses.

Sadly, I think we're still a long way away from a hive-theft deterrent device.



Mike Rossander



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