It's now the 16th or 17th day of nest building and the male has decided that his primary task is to defend his territory and keep watch over the female who I believe is a day or so away from egg laying. This morning, the female continued with the task of lining the nest using beech leaves, brought to the nest one at a time. The male very occasionally helped with a leaf or two, but spent the majority of his time sitting on a new "favourite" perch on my side of the river. Luckily this boulder is in perfect light for photography and consequently I was able to take some glorious photos of him. He seemed to encourage her in to the nest a couple of times, excitedly singing as he flew in before she flew in after him. I could then hear singing from inside the nest, again I suspect that mating took place inside the nest. I need to undertake some research in to this. As as yet I have not been able to find any information that this takes place. On another occasion the male went in to the nest without a leaf and then immediately flew out again with a leaf which he dropped in to the river. Quite why he did this we will never know. It's worth mentioning what a spectacle it is when the Dippers fly in with their brightly coloured leaves, the combinations of brown feathers, stunning white breast and almost golden brown leaves is a glorious sight. If you now study the photos of the nest you can see how much moss has been used, all carried in a few pieces at a time, an immense task and you can understand why it has taken 17 days so far. The male seems to be very alert to other alarm calls from birds in the nearby woodland. Not for the first time, this morning a Kingfisher flew up river calling loudly as they do. This was all too much for the male Dipper and he left very quickly in the other direction. I suspect that they are very vulnerable to hawk predation in the breeding season and their strategy is to leave nothing to chance. Sparrowhawk predation, or the threat of it might also explain why the Dippers are prone to fly way up river and feed hundreds of yards away from the nest. This area could be away from the Sparrowhawk territory. I know from my own observations that a Sparrowhawk regularly hunts close to the Dippers nest.