Sunday, 25 May 2014

Baby birds

This year seems to have the makings of a very productive year or at least it is starting out that way for some species. Having said that I have probably jinxed it now and we will be in for a miserable June and July but I hope not. Long-tailed Tits appear to be doing particularly well and many good sized broods are on the wing with some already joining together to form quite large flocks. Most of the other 'tit' species have recently fledged young in and it is hard to escape the noisy calls of the young birds along with the frantic food gathering activity of their parents. I haven't seen any young Blackbirds yet suggesting failure rates of local garden birds has been quite high so the picture is mixed as is often the case at both local and national level. Only time will tell and that is why ongoing monitoring is so important.

Unfortunately I have seen a lot of change in bird populations during my lifetime, some good and some bad, but most are man made in one way or another be it through climate change or changes in agricultural practices and the like. I would like to think I am not that old so these changes have been very quick in ecological terms and would have been very hard to imagine not that many years ago. Lapwings have disappeared from many farms in this area and have been all but lost from the remainder. The few remaining pairs rarely rear any young so local extinction is likely in the next few years.

On a more positive note this week saw the first juvenile Goldfinches following their parents into the garden. This is one species that is certainly on the up and has benefited from garden feeding, reclamation schemes and urban landscaping. Many pairs will have at least 2 or 3 broods so the garden should be full of them by September but that is only one increase in what is a sea of declines.

Juvenile Goldfinch
The once very common Starling is now red listed in the UK because of a recent rapid decline. I am lucky in that there are still quite a few nesting where I live although I have never been able to get a pair to use the nest box on the house. I attract a lot into the garden when they are feeding young by providing fat cakes and I have ringed about 50 adults this month and retrapped quite a few from previous years. I am considering starting a RAS project on them as I seem to have the ideal situation and population for this kind of project. RAS stands for Retrapping Adults for Survival and more information about RAS can be found here but it basically aims to establish the survival rates of adults to monitor and help understand population changes. It does require quite a lot of commitment over a number of years but as it only involves attracting local breeding Starlings to the garden it should be fairly easy for me to keep it going on a long term basis. Not quite armchair ringing but about as close as you can get. 

The number of young reared by each pair has increased as Starlings have declined but this increase in productivity per pair hasn't slowed their decline. This is because the survival rate of Starlings in their first year of life has halved over the same period and now only about 15% reach adulthood and get a chance to breed.
Only 1 of the 7 young Starlings in this picture is likely to survive the first year of life.

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