July has been a rather disappointing month for our ringing studies at Leighton Moss especially our normally most ringed species, Reed Warbler . Because of the windy and at times wet weather we have only been able to ring on 13 days compared to an average of 19 over the past 5 years. Inevitably this had led to lower total catches.
Our main study species Bearded Tit is doing reasonably well with 8 adult males and 9 adult females identified so far and a total of 24 juveniles ringed to date. Past experience suggests that the total breeding population is around 13-15 pairs. the numbers of juveniles ringed to date suggest a late poor first brood but second brood birds are now appearing.
We also run a RAS for Reed Warblers, to date we have caught 131 adults which given the decline in effort is around average. However productivity appears low to date. The 5 year average for our catch of juveniles in July is 223, this year it is only 93. The Sedge Warbler 5 year average is 74, this year we have caught only 30. Willow Warblers averaged 75 so allowing for the decline in effort this years catch of 58 juveniles is reasonable. Blue Tits despite their poor productivity in our nest box schemes also appear to be doing reasonably well with this years catch of 54 juveniles- 5 up on the five year average. Lets hope August brings both better weather and more birds.