Ornithologist, Phil Hanmer, shares an May update summarising bird monitoring across Northumberland throughout the month.
This May has been a dreadful one for most nesting birds, as was April; it’s been cold and wet and suppressed the natural food supplies as well as making it difficult for many birds to locate their food. I am not going to say anything much about Barn Owls because I have been leaving them undisturbed until June, in the hope that they would start nesting.
An unusual catch in the Mist Net in my garden at the beginning of the month was a large male Rook; attracted by bird food this bird had blundered into the net and seemed more puzzled by its predicament than alarmed. A more usual catch of the same morning were four Siskins; just showing signs of starting to breed. The signs of nesting (starting of brood patches on the females) were particularly pleasing to see as I have had nesting siskins near home for many years, although last year seemed to be almost a blank in this respect. I also captured two male Blackcaps who were singing loudly from opposite sides of the garden – and finally decided they really did want to ‘get at each other’ and were both caught at almost the same time! More specific monitoring took the form of checking 20 odd sights for Tawny Owls and only finding a single nesting female. I never have more than 50% occupancy but to only find one was disappointing. One lucky trainee got to ring the one owlet and re-process the female who has nested in the same location since at least 2017.
My Tawny Owls usually nest alongside our unusual nesting Goldeneye Ducks; with several locations typically having two Goldeneye and one Tawny Owl in three adjacent boxes. However, the goldeneye have done well this year, perhaps not surprisingly for a bird that regularly nests in the Taiga or Boreal subarctic forest regions of the northern hemisphere, and at least 15 females seem to have tried to nest. Unfortunately, we do have to discount 3 of these who were found dead and cached in a single box; having been predated by a tree-climbing Stoat. Yes, we did see the stoat as it made a leap reminiscent of a tropical flying squirrel out of its lair over my head – hitting the ground running and then carrying on going! Next time someone suggests we purposefully re-introduce Pine Martins to Northumberland do ponder on this. They do predate on goldeneye ducks in Scotland. Three of this year’s breeding females have all carried Geo-Loggers in the past – one was a victim of the stoat, but the others are very much alive – and so we do know where they spend their travelling time when away from the nesting grounds; this is a story which I will be pleased to tell you once the more usual evening meetings of the local natural history societies/clubs resume.
This month’s big job has been Nest Recording the small passerine birds that habitually use nest boxes to breed in, as well as a few who prefer to find natural holes or make more open nests. My trainees have been counting the eggs of Blue, Great and Coal Tits; and looking in vain for Redstarts and Pied Flycatchers, both of which we found last year. We have then returned to count hatched small pull and ring these when they have been large enough and survived the weather. One project at a local Caravan Site has done well with approaching 50% occupancy, while another near Ingram has only 10% occupancy. At a wood near Doxford occupancy is also approaching 50% and at a farm near Longhorsley is around 30%. These rough figures – which cannot be confirmed until the nesting season finishes – belie the facts that many birds have had smaller than usual clutches. Some have failed completely quite close to fledging, and Blue Tits are doing better than Great Tits. Tree Sparrows have also done poorly to date, but this is not a great worry because they will go on to have second and third broods, unlike the Tits for which it’s usually a one opportunity per season exercise.
We did find a nest of Chiffchaff eggs close to the ground (as they always are) at Ingram but it seems to have perished in the rain; and then much more successfully found a pair of very noisy Marsh Tits frantically feeding their 5 young in a tree hole near Longhorsley. The Marsh Tit parents seem to decide that Alison was not a threat and let her take the attached pictures.
In June we move onto the serious monitoring of Barn Owls and possibly a few Kestrels. If you think you have a Barn Owl nesting near you; please let me know.