More well grown tit broods

This morning we checked the nest boxes at one of our regular farms--and we have been trying some based on hollowed out birch logs as shown:-

There is a suggestion that these may attract tit species other than Blue and Great. This may be the case, but in our case this season, all the occupied boxes contained Blue and Great tits. Most were too well developed to ring--if you're not very careful they can burst out of the box before they are absolutely ready so we tend to leave these well alone.

The best age for ringing is usually just as the flight feathers are bursting out of their sheaths:-

This brood of Great tits was just about perfect for ringing--there were 7 ( about average) of which these 4 were not camera shy.