In early September we were paid a visit by Renaud Flamant, the European colour-ringing co-ordinator for Mediterranean gull. Renaud’s itinerary included a couple of days in Gower, a brief stop in Carmarthenshire and a visit to Ceredigion. His plan was to confirm the areas of greatest importance to Mediterranean gulls, and to read the colour rings of as many birds as possible.
Over the course of his visit he met up with or spoke to a number of Gower birders who have returned colour ring records, including Bob Howells and Lyndon Jeffrey (by telephone) and Alun John, Tate Lloyd, Eddie Hunter and Owain Gabb (in the field).
Mediterranean Gull numbers and behaviour in Gower
Despite only being in Gower for a couple of days, Renaud made some very interesting observations.
- He counted approximately 600 Mediterranean gulls in Swansea Bay at dusk. Consistent with his observations from other sites in western Europe, he found the gull numbers in the bay to be focussed around the areas where streams issue onto the foreshore (the stream at Blackpill / opposite Clyne and the outflow by the West Cross Inn). He also noted that the numbers of Mediterranean gulls built up over the course of the late afternoon. Birds were noted washing and preening before eventually moving into the inshore waters of the bay to roost just after dusk.
- He found that birds present at Port Eynon and Bracelet bay during the day commuted back to Swansea Bay to roost. The Gower population (birds are seen in low numbers on most Gower beaches) is therefore likely to be one entity focussed on Swansea Bay.
- He managed to read the rings of 85 Mediterranean gulls in Gower, most of these being birds in Swansea Bay. He read another 30 colour rings on Llanelli beach and 49 in Cardigan Bay, taking the overall total for the week to 164 records. A number of birds were recorded twice, and the tally was 100 unique individuals.
- These birds originated from colonies in:
- Belgium and the Netherlands (45)
- France (27)
- Germany (14)
- UK and Ireland (7)
- Poland (3)
- Hungary (2)
- Czech Republic (1)
- None of the birds was observed in more than one of the counties visited over Renaud’s brief stay, and the wider data set does not currently indicate much evidence that they use more than one area over winter. However further ring reading would be useful to confirm this.
- Approximately 5.5% of the flock in Swansea Bay is ringed. Based on extrapolation, Renaud calculated approximately 800 birds to be present (similar extrapolations elsewhere have been found to be accurate when tested). The true size of the roosting flock is extremely challenging to count as birds continue to join in very low light conditions, and start to depart to forage inland (including on sites like the sports pitches at Ashleigh Road and Sketty Lane) before sunrise.
Where do you fit in?
In a couple of days Renaud ring-read more Mediterranean gulls than anyone has in Gower other than Bob Howells, who recorded birds at Blackpill over many years and returned a total of 356 records. He noted that there is huge ring reading potential locally, but (sadly) no-one is actively studying the birds and returning data to the ringing scheme.
This is important as Mediterranean gull winter distribution is changing, with the species becoming far commoner in Wales in winter over recent years. Many of our sites now host internationally important populations, and to conserve them effectively we need to understand the network of areas they use when breeding, on passage and in winter.
The best time for ring-reading is August to October inclusive, as this is when the largest numbers of Mediterranean gulls are present. Other than in the spring and early summer (when they depart to breed), however, birds are always around.
Our own observations of the colour-ringing scheme (as local birders) is that information on life histories of birds is returned extremely rapidly (usually within a day), and that this reveals some fascinating detail about where individuals breed and where they have been seen on passage. Birds also reach good ages, with one venerable individual (white E825), initially recorded in the area by Bob Howells, and subsequently by most regular birders in Swansea west, being in its 14th year.
Please do get involved and submit sightings.
Birds can be reported via https://www.cr-birding.org/colourprojects
A photo of Renaud and some of the colour-ringed birds he is responsible for follow. There are different colours used in different European countries as the photos of local birds taken by Alun illustrate.
You can also see that the rings can be easily read in the field using a telescope with a little bit of patience.