Awesome article and very interesting. However to go on a bit of a tangent what did people think of the sensor in the photo? It's interesting that such as small sensor still has long pads for connecting (presumably to program it and get data off) and also that it has a little tag on the left of the picture (making it bigger). I can't see a battery in the photo. Is it on the backside or is it powered in some other way? Also what is the little metal wire for? I would think that it was an antenna, however they state that they had to find the birds again to get the data back so it would seem that they don't communicate wireless. Could it be getting powered from radio waves instead? What do you think? Is there more information on it somewhere?