As well as a general report of birds in/over and breeding in the City for our NatHistCam project over the study period I have asked Cambridgeshire Bird Club members to take part in a survey of Blackcaps in the City seen in winter. This blog is to invite anyone who would like to, to take part and contribute. The Blackcap warbler is mainly a breeding summer visitor but is overwintering in increasing numbers.
The objective is to record the number and distribution of
wintering Blackcaps in the project area.
Blackcaps readily come to garden bird feeders and like “Starling” bars and sunflower hearts. They are considered our most efficient Mistletoe spreading bird species. They are greyish warblers the size of a Great Tit – the males have a black crown and the females a brown crown – “browncaps”. They have a distinctive call – a loud, sharp “tak tak tak….” like stones being hit together. Their call is often the first indication they are about. It differs from the softer “tik tik ….” of Robins.
The British Trust for Ornithology in their Garden Birdwatch project (Plummer, K.E. et al 2015) says the availability of garden bird food and milder winters has helped Blackcaps evolve a new migration route and new behaviour. Blackcaps breeding in S. Germany and Austria now migrate NW to Britain instead of SW to Spain.
Roger Isted, a Cambridgeshire Bird Club member found, using coloured rings, 12 different Blackcaps used his garden in winter 2012/13 and 13 different Blackcaps used his garden in winter 2013/2014 – all were different individuals from the winter 2012/2013 (Isted, R. 2010, 2012, 2013). Rebecca Buisson in her Cambridge garden bird survey has already collected some records for this winter (October to December 2016) with single birds recorded in Riverside, Newnham, Cherry Hinton and Mill Rd Cemetery. Other Bird Club members have seen one in Chesterton Hall Crescent, a pair in Benson St and I saw a male in Union Lane on 11th December 2016.
These pictures show male and female Blackcaps in my Chesterton garden in February 2015. This survey would be a useful bench mark against which future surveys could be measured.
The information requested is: Date seen; where seen (street name); male or female. Optional are any other observations such as feeding habits – what are they eating (especially if Mistletoe berries), display/aggression.
The project will last until to March 2019 covering the winter periods: 2016/17, 17/18, 18/19.
Please send winter Blackcap records to me:
bobjarman99@btinternet.com.
I will also send our records to the Cambridgeshire Bird Club Recorder and they will be written up as part of our project.
Male Blackcap (BTO) 
Bob Jarman
January 2017