I had to visit later than usual today and was concerned to see that, according to the NoFence Collar map, three of the cows were in D4 while one was in E/F5. The map had shown this for several hours so I was hoping that this was an anomaly and and there wasn't a cow by itself among the silver birches. As it turned out all four were lying together in the open space to the SE of the hydrant pool. When they heard me approaching all four stood up attentively. All of them appeared well but were clearly disappointed that I wasn't Gordon! They did try to trot after me as I left though.
I checked they all still had their collars attached, which they did, so I'm guessing that one of them stopped working while they were all in the birches at some point. The following photo shows the locations shown on the map when I left and the serial number of the collar showing the wrong location.
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