The Last CES Session of 2019: Lower Moor Farm, Wednesday, 28th August 2019

A Constant Effort Site (CES) comprises 12 sessions between the beginning of May and the end of August / first week of September. Each session is scheduled within a window of 10 days predetermined by the British Trust for Ornithology (BTO).  Nets are set in the same positions, and are left open for the same length of time (6 hours), for every session year on year.  This the fifth year that we have run a CES at Lower Moor Farm and it has reversed the trend of decline observed over the first four years.  With the exception of last sessions blip, every session has been a significant improvement on last year.  It has become the best year so far, as the following table shows:

CES Summary

Essentially, the site has recovered significantly, even surpassing the opening year of 2015. Today’s was session 12 of 2019.  I had expected to be joined by Andrew Bray and David Williams for the session only over the course of Tuesday afternoon and evening I got messages that Jonny Cooper, Ellie Jones and Henny Lowth wanted to come along.  Last year this session delivered 39 birds so, whilst I didn’t want to put anyone off, I was worried whether we would have enough of a catch to make it a worthwhile venture for them all.  I needn’t have worried. 

The list from today was: Kingfisher (1); Woodpigeon 1; Great Spotted Woodpecker 1; Green Woodpecker (1); Nuthatch {1}; Treecreeper [2](2); Blue Tit 2[4](3); Great Tit (1); Long-tailed Tit {2}[3](4); Wren [1](1); Dunnock (2); Robin [2](1);  Blackbird (1); Blackcap [33](4); Garden Warbler [1]; Whitethroat [1]; Lesser Whitethroat [1]; Chiffchaff [9]; Goldcrest [2]; Bullfinch 1[2]. Totals: 3 birds from 2 species ringed unaged (Nuthatch and Long-tailed Tit); 5 adults ringed from 4 species; 61 juveniles ringed from 12 species and 21 birds recaptured from 11 species, making 90 birds processed from 20 species.  Of the recaptured birds 14 were also juveniles.

Andrew did a great job of getting to the Woodpigeon before it managed to escape the net.  Large birds can be pretty adept at getting out of the nets, particularly the 5 shelf, as opposed to 4 shelf, nets we use.  This gave David the opportunity to ring his first Woodpigeon.  He found out that there are different skills needed to handle a bird of that size and strength, but with a bit of help and direction he handled it well. Henny was also delighted to be able to process her first Kingfisher and Green Woodpecker, although they were already ringed, she carried out the ageing, sexing and biometric measurements.

Given that we have only 12 metres of net within woodland for the CES, the vast majority being within the scrub that lines the lakeside and the trees that line the stream marking the boundary between Wiltshire and Gloucestershire, it has always been a surprise how many Treecreepers we catch at the site. Today we caught our first Nuthatch for this side of the site. Two caught in March 2016 were in the vicinity of the Visitor Centre / Education Area. Couple that with two of our three woodpecker species, it was quite a woodland catch for a non-woodland site!

We were joined for the morning by Tony Marsh. Tony, along with Robin Griffiths, are the two people who regularly send me sightings of my colour ringed Marsh Tits. This is a project I have been running, now in its seventh year, for this species. On the left leg they have a BTO metal ring with its unique number plus either a red, blue or green colour ring. On its right leg it will have a combination of two coloured rings. If you should see one of these birds and send me a sighting through the comments section of the blog, I will send you the details of that bird (when ringed, how many times it has been recaptured / seen) and be eternally grateful.  I know that Tony enjoyed getting some close encounters of an avian kind!