In these unusual times when we're restricted to garden ringing, it's a good opportunity to look at our data and try some interpretation.
I am by no means an expert but have had a couple of previous attempts with the Bullfinches and Willow Warblers I catch at Goosedale Fisheries (which can be found in the 2014 and 2016 group reports) so I thought I would update these for the blog.
Unfortunately, the annual survival estimates were so poor I don't want to include them. The numbers of new birds ringed is both encouraging and disappointing at the same time (see graph) and it's important to poimt out that these figures can't be viewed as definite population trends over such a short period and in such a random study.
I thought I would also look at the sex ratio of the new Bullfinches caught. You can see variation over the 5 years but interestingly after the study period the totals are almost the same. The unsexed birds were juvenile birds still in their juvenile plumage.
This type of analysis is not going to re-write science, but it does add another dimension to understanding 'our' birds and how they are doing.
Give it a go!
Mick P
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