25 Aug 2019


When I first started ringing in the 70's rings were free(!) and you had to pay to ring House Sparrows and Starlings. How things have changed! Starlings have declined by a staggering 51% in the UK between 1995 and 2016 - see Birdguides article here.

The strange thing is that we don't see Starlings regularly in our garden but small numbers breed locally and a friend, a few hundred metres away reports, he gets large numbers on his garden feeders. We do get wintering birds and when the local farmers spreads slurry on his fields flocks of up to 500 are regular. Since I retrained to ring a few years ago I'd only ever ringed Starlings on Fair Isle!

They're still common on the north Wirral coast though and Jane was reporting daily flocks of 100+ visiting her heavily fed garden. We decided to start a project catching and ringing some of these birds using a whoosh net (a net powered by elastic - once the tension on the elastic is released the contraction pulls the net up and over two poles and over the birds feeding on the ground. They're then covered with old sheets to keep the calm whilst we extract them for ringing (A special endorsement is required to use a whoosh net which I have). My whoosh net has been modified to incorporate an automatic release so rather than using a long piece of cord to fire it it is now done using a car door solenoid and remote fob powered by a 12 v battery. Video below.

We've now caught a good number of Starlings and they've all been juveniles with the majority undertaking their full post juvenile moult. Most passerine species only undergo a partial post juvenile moult but Starlings (along with a few other species such as House Sparrow and Long-tailed Tit) undertake a full moult including wings & tail.

Male and females can be identified from an early age as females have an interocular eye-ring (see photo below) whereas the males have an all dark eye. Some birds were left unsexed due to uncertainty over a very faint interocular ring.

If the birds have started moulting their body feathers theres another sexing method that can be used - the shape of the white spots on the breast feathers. This can be useful in confirming the sex of those birds where the presence of an interocular eye-ring is less clear cut.

Females tend to have round spots whereas males are more arrow shaped and pointed. The photo below illustrates this well with the female on the left and the male on the right. You can just about see the interocular ring in the eye of the female as well.

Most of the birds are also well on the way to completing their wing moult with very few classed as 3JJ (fully juvenile plumage). Moult was recorded for every bird along with sex, weight and wing length. Photo below - wing being examined and moult score for each primary being recorded.

It was also noted that some of the birds had very bleached juvenile plumage whereas some were much darker and it was assumed the darker birds were second broods (or late broods).
To date we've ringed 283 Starlings, in Janes garden, of which only 1 has been an adult. To put that into perspective in the whole of Cheshire in 2018 0nly 425 Starlings, of which 238 were juveniles. We've exceeded the total of juveniles ringed in the county for the whole of last year in less than 1 month!

We intend carrying on over the winter with this project and it'll be interesting to see how many re-traps we get and if we get any continental controls. Ultimately it would be nice to register a colour ringing project to see how many of these birds are actually local breeders and how many have arrived following post juvenile dispersion from their natal sites.

Many thanks to Jane for supplying tea, cakes and starlings and Helen and John for the invaluable help.

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