Tuesday, 11 August 2015

Where are the Willow Warblers?

I managed short trips to Maridalen and Fornebu today in overcast conditions and really noticed how few Willow Warblers there are. At this time of the year this species should be in every bush but I could not have had more than 10 during the whole day. I have been hoping that the low numbers are due to breeding being delayed due to the late spring but now I fear that breeding success has just been catastrophically low and there are very few young birds around. I also had no Bluethroats today which I had hoped to find although it is still early days for this species.

Not all insect eating species seem to have had a bad season though. Swifts (tårnseiler) and Swallows (låvsevale) seem to be abundant as are White Wagtails. Red-backed Shrikes also, and surprisingly, seem to have had a good season and in addition to the 3 young birds still in Maridalen I had three youngsters at Fornebu. Two Redstarts and a Pied Flycatcher were unusual autumn migrants to find at Fornebu and maybe these species have also had a god year.

In Maridalen I glimpsed a Honey Buzzard and heard a Redshank which is an unusual autumn record here.
one of the Red-backed Shrikes (tornskate) at Fornebu
Redstart (rødstjert) at Fornebu
can you see the 3 wader species in this shot from Storøykilen, Fornebu?
Lesser Whitethroat (møller) and Whitethroat (tornsanger) from Fornebu

this newly fledged Blackbird (svarttrost) was still being fed by mum. It is quite a late date but the mum had a very easy job collecting food. They were sat in a berry tree and she just collected berries and dropped them in juniors open mouth

I'm not sure which species this caterpillar will grow up to be but is I assume a moth rather than butterfly. A google search of "caterpillar red spike tail" suggests it is a Bedstraw Hawk Moth (hyles gallii) (mauresvermer)



  1. Interesting that you are finding far fewer numbers of Willow Warblers than expected. We are finding the same here (Bardsey Island, North Wales). Usually we would have had several 100+ days by now, but 50 today is the highest number we have seen so far. It is hard to tell here whether the low numbers are due to the weather or breeding success. Thanks for posting, Ben Porter

  2. Ben, I also understand that there are low numbers than usual at Lista Bird Observatory on the south coast of Norway so it seems that it is not just a local phenomenon. Do you know where the Willow Warblers on Bardsey come from? Are they British breeders or Scandinavian?