We had selected a location the evening before and set three nets in a triangle around an isolated small tree. The nets were furled for the night. Before first light we opened them, placed a stuffed Cuckoo within the triangle and turned on a tape lure. Shortly after dawn we heard a Cuckoo calling but by 5am all was quiet so we went to check the nets in case it had been caught. Much to my amazement, we had not one but three Cuckoos; one in each net!
This created a bit of a problem. Fitting satellite tags is a delicate and precise process and cannot be done quickly. Would keeping all three birds for tagging mean that the last bird was in captivity for too long? Problem solved though because tags can only be put on birds weighing 115 grams or more and one weighed in at 113g so it was just ringed and released.
It was a real education helping with the tag fitting. Great care has to be taken with ensuring that no feathers are trapped under the harness and the positioning and fit of the harness has to be remarkably accurate. When everything is done, checked and rechecked, he's ready to go.
We moved to a new site a couple of kilometres away and set the same pattern of nets with stuffed bird and tape. The wind had picked up by now and I wasn't sure whether we'd have any further success. The BTO researcher had allocated three days for catching the required four Cuckoos but with the forecast for the next couple of days being dodgy, we needed to make the most of a dry day. I needn't have worried as one bird of the required weight was quickly caught and after processing that bird we found another two in the nets with a further bird in a tree nearby. I would never have believed that there were so many birds in such a small area if I hadn't seen it for myself. One of these two birds was only 111 grams so we ended up with exactly what we needed and by mid-day we were done and packed up.
It was fascinating to hear about all the technological advances taking place and the potential projects on the horizon which will revolutionise our knowledge of, particularly, migrant birds. It's an exciting time to be involved in bird research, even if only as an enthusiastic (even after a 3am start!) amateur.
No doubt the four tagged New Forest Cuckoos will appear on the BTO web site in due course and we will all be able to follow their fortunes as they hopefully make it down to west Africa for the winter and back again next spring. You will not be surprised to hear that I have put the case for one of them to be named Gilbert!
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