CES 2021 Commences

with No Comments

Gower Ringing Group’s Constant Effort Site (CES) at the Wildfowl and Wetland Trust’s Penclacwydd (Llanelli) reserve recommenced on 29 April 2021.

CES was the first standardised nation-wide ringing programme established by the British Trust for Ornithology (BTO), and has been running since 1983. CES ringing requires that ringers operate the same nets in the same locations over the same time period at regular intervals through the breeding season. Over 140 sites CES sites operate across Britain and Ireland. The Scheme provides valuable trend information on abundance of adults and juveniles, productivity and also adult survival rates for 24 species of common songbird.

The first visit to WWT Llanelli resulted in the capture of 37 birds. Totals are below:

Highlights included a bullfinch ringed in 2017 and a blackcap ringed in 2018. Both were adults on first capture, to in at least their sixth and fifth calendar year respectively.

Due to restrictions on ringers resulting from lockdown, and the opportunity to obtain data on species not particularly well sampled by standard CES and other projects, the BTO established the Garden CES in 2020. The principles of the scheme are the same, albeit feeding is permitted.

The first garden CES session of 2021 was carried out by Heather Coats on 2 May in her Crynant garden; 34 birds were captured. Totals are below:

The highlight of the catch was a female lesser redpoll, a species noted infrequently in the garden. All of the 20 siskins captured were adults; an interesting result given that large numbers of juveniles were recently captured at Oxwich.

Both the CES sessions were led by Heather Coats, who would like to thank to Colin Baker and Ezra Sherwell for help at WWT and Tom Wright for help in the garden.

A photo of the lesser redpoll is below.


Gower Ringing Group


Notify of
Inline Feedbacks
View all comments