Blog post by Vivien Hartwell, Research Assistant, RSPB Centre for Conservation Science.

Starlings are one of the UK's fastest declining birds. And we want to know why.

Back in May we started a new and innovative project in Bristol that will hopefully shed light on where juvenile starlings move to after fledging. 

The aim is to find out where they go, the habitats they use and what threats they face as they disperse away from their nests.

So how is the project going, and what have we found so far?

Urban starling. Image by Ben Andrew (rspb-images.com)

Catching starlings

After a month of trying across four gardens in Bishopston, Easton, Henleaze and Southmead we successfully caught 60 starlings.

These were a mix of adults and juveniles. Of these we were able to carefully place radio tags and colour rings onto 25 juveniles, while another 14 which just had colour rings fitted.

Many adults were caught showing evidence of nesting behaviour and as June went on more were showing signs that they had completed breeding and were starting to moult their feathers.

The birds were mainly caught using mist nets and potter traps (box traps which a bird walks into, before a door closes behind it) and all users were permitted by the British Trust for Ornithology to use them. All of the birds caught looked healthy.

Juvenile starling with colour ring. Photo by David Buckingham (rspb.org.uk)

Juvenile starling with colour ring

What's next?

Now the hard part starts trying to find where the starlings have gone. For the first month after fledging many of the birds we tracked stayed within 4kms of where they were caught. Now they appear to have moved to new areas with sightings of the birds becoming rarer.

Many sightings so far have been in gardens, with the starlings using feeders filled with meal worms and suet balls, and also drinking and bathing in the bird baths.

Over the coming month I will be travelling around Bristol trying to find the tagged individuals using traditional tracking technology and comparing it to the newly designed tracking boxes the RSPB have designed.

I will use both side by side to try to find the birds and to see how the new technology compares to the traditional methods. We hope that in future these new tracking boxes can be given to more members of the public to help us find birds which disperse rapidly, like starlings.

We currently have these boxes in gardens in northern Bristol and with volunteers that are using them as they travel around the city.

Juvenile starling fitted with satellite tag. Photo by David Buckingham (rspb.org.uk)

Juvenile starling fitted with satellite tag. The tags weigh just two per cent of a starlings total weight.

Did you see us on BBC Springwatch?

In June, the BBC Springwatch cameras came to feature the project on their show. We were very lucky and managed to find one of the radio tagged birds within 15 minutes of looking! The starling was very obliging and stayed in a collection of gardens in the city which we were able to access to look for it.

As soon as the filming was finished the bird and the group it was with moved off and the radio tracking equipment no longer picked up the bird’s presence in the area. The bird was found again on several occasions after this but now appears to have moved elsewhere.

Vivien Hartwell with BBC Springwatch presenter Patrick Aryee. (RSPB)

How can you help

This is where we need you! Any sightings of the colour ringed or tagged birds are valuable to tell us where they have gone to. Extra details letting us know where they were seen and what they were doing is equally as valuable to help build up a picture of their behaviour around the city.

If you see a colour ringed or tagged bird in Bristol, please email vivien.hartwell@rspb.org.uk