Tuesday, October 30, 2012

A final batch of gull ring readings from the Taboeira landfill…



Ok, I realize that I’ve announced the closing of the Taboeira landfill far too often on this blog, but this will ‘probably definitely’ be my last entry about the site. In the previous entry you could read that gull numbers out there apparently had increased recently, and I will explain here in detail what has happened.
On my last few visits to the site the number of gulls was reasonable (8-9000 birds by the end of August, increasing to about 10.000 – 11.000 birds on my last visit on September 7), but with a notably decreasing amount of waste being transported to the site I suspected that things would be over soon for the gaivotas. When passing the official closing date of October 8, I believed no gull would set foot on Taboeira anymore and today personnel informed me that about a week ago not a single gull was present at the site. Around the same time it became obvious that gull numbers around Aveiro had dropped notably.
After the valuable tip I received last Saturday about the high number of gulls that currently can be found at the landfill, I figured this could be my last chance to get some serious gull-ring resightings. The saltpans and mudflats certainly are a nice place to work, but the number of gulls with readable rings there are only a fraction of what can be found at Taboeira, within the same amount of time.
So, this morning I got up early for ‘The Final Taboeira Visit’. However, while on my way I noticed something strange… A rather large number of gulls was flying over me, coming from the west (from roost sites in the Ria) and heading to the southeast… This appeared to be a bit odd; as long as we live here in Aveiro the gulls from the Ria travel northeast to get to Taboeira in the morning, and fly back to the southwest by the end of the day. At that point I highly suspected that a large number of gulls by now have found their way to the new landfill site (Eirol)...

Commuting gull routes in the early morning of October 29 2012: Black arrows are flight paths, red line is the road to Taboeira (small light blue circle) and Eirol is the larger dark blue circle. Only from about 2 km from Taboeira did I notice gulls flying to the original site.

At arrival at Taboeira at 7:00 there was a very good number of gulls present (around 20.000), which reminded me of the hay days of the site (but double this number to get to the best days in December 2011 – February 2012). It turned out that even though the site had stopped accepting waste since October 8, a certain amount of waste is being imported from the new site in Eirol, in order to be able to level off the last mound, before it will be covered up with soil completely in only a few days from now. And then the gulls will be gone.

 



During the following 5 hours I managed to read 35 rings, including 33 Lesser Black-backed Gulls and 2 Black-headed gulls, and these were applied in Britain (12) The Netherlands (8), Guernsey (6), Germany (3), Denmark (2), Norway (1), France (1), Belgium (1) and Poland (1). The number of rings read could have been a lot higher, but I decided to take the opportunity to chat up with several of the site’s personnel on this final visit. They’re all very nice people out there, and ERSUC has been very supportive during my visits. Thank you all!

 Oh, yeah, gull rings... Peter Rock's BLUE T+U, WHITE inscription, from...around Bristol, UK?

 Black-headed Gulls were common in the winter at Taboeira, but they allways got totally outnumbered by the LBBG; today about 1000 of 'm were present, including this WHITE 521, BLACK inscription from Denmark. Today another BHG carried a ring from Poland.


A new bird on the site? LBBG adult; GREEN Y.AKU, WHITE inscription, ringed as an adult by the Cottaar-Verbeek ringteam in 2009 at the 'Forteiland' in IJmuiden, The Netherlands. The bird has only one other record outside of the Netherlands (Belgium, Zeebrugge beach, October 8 2010). 
One of the employees gave me this LBBG(?) leg with a Brussels’ metal ring which he found some time ago. I passed it on to Eric Stienen (Belgium) who will do the paperwork, I hope.