Of matters avian and aeronautical

First, aeronautical. UK airspace has been pretty much closed following the eruption of an Icelandic volcano. The volcanic dust is highly dangerous to aircraft as it can jam the engines and even seep into and corrupt passengers' air.



The picture shows the Met Office ash cloud forecast for 7pm BST on Thursday 15 April, issued at 6.35am. The red areas show the risk of ash at lower levels between ground and 20,000ft - marked in "flight levels" as FL200 - while green areas show the risk of ash between 20,000ft and 35,000ft, marked as FL200/FL350.

Blue areas show the cloud between 35,000ft and 55,000ft - marked as FL350/FL550.

The spread of all three layers over southern England suggests even more disruption to flights is expected later today, as controllers extend air space closures, currently affecting every UK air traffic 'sector' north of London.

It is not known how long the disruption will last, so I'm wondering if my daughter will be able to get back from Portugal in time for the start of the new term next Monday (she is a teacher).

As for matters avian, I have been watching house sparrows, a hedge sparrow, blue tits and blackbirds gathering nesting material over the last few days. The blackbirds have chosen a spot in our neighbours' tree, which is right beside the fence. It's a pretty dense tree with ivy growing up through it. I have seen the cock bird occasionally, but it seems to be mainly the hen doing the nest building. She has imposed a one-way system, flying into the tree on our neighbours' side and out on our side. She generally lands on a post in our garden quite close to the tree where she sorts out her plumage, which gets ruffled as she exits the tree, before going foraging again. It's for all the world as though she is primping her hair before going out and really is quite amusing to watch.