Starling RAS half time scores

This year's Starling RAS has just passed the half way mark and 89 different adults have been recorded in the garden in the first 18 days. My RAS period is relatively short and runs from 21st April to 24th May but it still requires a plenty of commitment as I usually clock up at least 100 hours of effort over that period. Now if you don't know what a RAS project is you can find out more here and here but in simple terms it allows adult survival rates to be calculated from retrap or resighting data gathered over a number of years from a ringed population of breeding birds.

As I have been running a RAS project for a few years now the majority of Starlings that breed within foraging range of the garden are already ringed with both a BTO ring and a numbered colour ring so most of the effort involves recording colour-ringed birds when they come to feed. My Starlings are pretty well trained and come to a supply of home made fat cakes in a cage on a bird table and hung in a tree near a window. This means I get to do most of the observations from the comfort of an armchair and with a plentiful supply of coffee at hand. Any unringed birds are easily caught for ringing if they enter the cage to feed as the door on the cage is closed via a string that comes in through a window.

Ringed birds like this one (E11) happily feed in the cage as the door is only closed if an unringed bird enters. E11 was originally ringed as a juvenile last year. The fat cakes I make are an irresistible mix of beef dripping, dried mealworms and finely chopped peanuts.

Of the 89 adults recorded so far 65 were ringed in previous breeding seasons with 47 being at least 2 years old and the remaining 18 being ringed as juveniles last year. If those birds are representative of the local population as a whole it means 72.3% are experienced breeders and just 27.7% are breeding for the first time. There is still plenty of time for other colour-ringed birds to be recorded so it will be interesting to see what these figures look like at the end of the RAS period.

D25 has been resighted numerous times this season and was originally ringed as a breeding adult in 2016.

The primary aim of a RAS project is to establish the survival rates of adults but it has to run for at least 5 years before the data gets processed by the BTO and this is only my 3rd year of intensive study. However, the high proportion of colour-ringed birds recorded so far suggests it will produce some useful results in due course.

They really are a smart looking bird. In addition to providing fat cakes I occasionally throw bread, suet pellets and a few dried mealworms on the lawn.

I happened to photograph this Starling having a quick shake.