I’ve been bird ringing in the region for around 50 years, and Siskins have always been a rather special bird to me for many reasons. They are lovely to look at, easy to age and sex, reasonably easy to catch and they tend to move around far and wide, so providing much interesting data on bird movements.

Siskins typically turn up in gardens in springtime. This is the period when they roam around looking for food because their natural food ( alder and birch seeds) is running out. Those readers who are as long in the tooth as me will remember that in order to attract Siskins we used to hang peanuts out in red mesh bags. Move forward to current times and, like so many garden visiting finches, Siskins love sunflower hearts.

In recent spring seasons in our region, our group members have ringed no more than a handful of Siskins. We began to suspect in February this year, that we may be on for a good ‘Siskin year’ when we ringed around 50 birds in a small number of regular ringing sites within a small radius of Brewood.

However, on the 3rd of March, alarm bells really started to ring at one of our regular public ringing demonstrations at Jubilee Wood local nature reserve near Billbrook. The typical species at these events are mainly Blue and Great Tits, with a spread of other typical garden species. This session was very different in that out of a bigger than normal catch of 81 birds, 40 of them were Siskins, with 10 Lesser Redpoll and 1 Common ( Mealy) Redpoll!!

This last bird pointed to a possible source of these birds because this race of Redpoll breeds only on continental Europe.

Keri and Annette, who organise things at Jubilee Wood, agreed that we should continue to ring as much as possible at the site, to see if we could ring any more Siskins to find out where they had come from. What a great decision that was! Many team members took advantage of the offer and throughout the rest of March and early April we managed to ring 904 Siskins at the site using only 1 of our shortest 6 metre nets! We suspect this must be some sort of record for such a short net. But way more important was that it demonstrated just how many birds were involved. And this was further reinforced by team members also catching big numbers at various nearby sites; Kingswood Trust, Brewood Park Farm and members’ gardens, so that in total we ringed over 1500 Siskins in around one month.

Conversations with birders and the general public in the area confirmed that there were plenty of other birds making use of the food that was being provided, mainly in gardens. We feel this really does qualify as an invasion.

Intriguingly however, in conversations with other ringers outside the immediate area, in North Staffs, Notts, Worcs and Sutton Park, they reported no such numbers; and in the case of our friend Rob whose garden is on the edge of Sutton Park he had not ringed or seen a single bird.

The question looming large for us was of course—where on earth are these Siskins coming from? Fortunately part of the answer became evident fairly quickly. One of the greatest thrills for a ringer is to catch a ringed bird which isn’t one of ‘your own’—even more so if the ring has been put on in a different country. Imagine the excitement when over the course of just a few days, we caught 4 different birds which had been originally ringed in Germany, Czech Republic, Poland and Lithuania!!

There are very few records of Siskins being ringed in these countries then recaptured in the UK. So these birds gave us a clear indication of the origin of at least part of this invasion—eastern Europe. This linked back nicely to the Common Redpoll we ringed as mentioned earlier.

Shortly after we had sent off the ring details of these birds, the precise locations and dates of the original ringing began to come through on the on-line database, as we have shown below.

Plate 1.

The red spots indicate where these 4 Siskins were originally ringed, prior to them being re-caught in our area

We had hoped that some of the birds WE ringed may have been re-trapped in some of these countries, as they returned to wherever their breeding grounds are. Sadly, to date none has, though we remain hopeful.

So, just when we thought we had ‘cracked’ knowing where the invasion had originated, we had to put our thinking caps back on. We did start to receive reports of some of the birds we had ringed during the invasion—but rather than being them being found in eastern Europe, most had moved to......Scotland! See Plate 2 below.

However, 2 birds may be on their way back to eastern Europe. The most obvious one was recaught in Sweden, so it had already crossed the North Sea and was well on its way. The other blue spot indicates a bird that was re-caught in Suffolk. Was this building its fat reserves ready to cross the North Sea also? Shortly after we put some of this material on ‘X’, colleagues at the BTO confirmed that there had been other Siskins ringed in the UK, which had already been re-caught en route to eastern Europe.

So, it appears that the invasion of Siskins into our area, was of birds originating in at least 2 geographical areas at the same time. One population from northern England and Scotland; and the other from eastern Europe.

Plate 2 Each blue spot indicates where individual Siskins were re-caught only weeks later.

So, yet again this hobby of ours has provided an insight into bird behaviour which wouldn’t have been know without rings being put on. We await news of any of the birds we ringed turning up in Germany, Czech Republic, Poland and Lithuania—but next time you see any Siskins on your bird feeder just stop for a minute and consider where they may have come from in order to benefit from the food you are providing.

Thanks to the owners and managers of all the sites we used; all team members who gave their time to ring the birds, and to team member Pat, for creating the maps

Colin McShane on behalf of Belvide Ringing Group, June 2024