Gulls at the Eirol landfill, Aveiro (Portugal): March 11, 2014

On March 11 Pedro Moreira and I visited the Eirol landfill again. We searched for rings between 7:00 and around 14:30. The weather was great, no or hardly any clouds and a lot of sun, probably a bit too much for the time of the year. There were fewer gulls present; about 9.000 Lesser Black-backed Gulls, 1500 Black-headed Gulls, 40 Yellow-legged Gulls and two Mediterranean Gulls. Highlight of the day was a first observation of a Common Gull for the site. We managed to read the rings of 35 Lesser black-backed Gulls and 2 Black-headed Gulls.

 Common Gull Larus canus

Procambarus clarkii is a freshwater crayfish species, native to the Southeastern United States, but found also on other continents, where it is often an invasive species. In this area these tasty snacks are taken by White Storks and Lesser Black-backed Gulls in marshy areas. They can currently be found around the landfill in large numbers in the shape of regurgitations that were dropped there primarily by the gulls, I suspect. The number of storks is currently very low; we counted only one during this stay, though it might be possible that more storks visit the site at later times of the day. On the other hand, the recent floodings in the area might be very beneficial for the storks (as well as for Procambarus clarkii?) so there maybe is no need for them to come to the landfill. I hope that the people involved in this study: http://www.bto.org/science/migration/tracking-studies/stork-tracking/about are aware of relatively recent and increasing occurrence of Procambarus clarkii in the White Stork’s wintering areas.

Lost racing pigeon Columba livia forma domestica, with a ring we did not manage to read.

 Two photos of the first recorded Water pipit Anthus spinoletta for the Eirol landfill (thanks to Pedro).

Dead British seabirds are finding their way to Portuguese beaches?

A survey of stranded seabirds on the Atlantic coast of France has found more than 21,000 of their corpses washed up on shores between Brittany and Spain.

A co-ordinated count that took place last weekend (22-23 February) from Finistère to the Spanish border resulted in 21,341 dead birds begin retrieved, along with and another 2,784 brought to veterinary centres to aid recovery. Several thousand dead seabirds were already counted earlier in the month and fishermen and other boat users reported that there were "carpets of dead birds" still floating at sea.

See http://www.sott.net/article/274701-Update-Tens-of-thousands-of-dead-seabirds-have-now-washed-up-in-Bay-of-Biscay

Today on only a short walk on the beach near Praya de Mira (< 1 km) we found these two Puffins Fratercula arctica and one Black-legged Kittiwake Rissa tridactyla.

Fratercula arctica; but where did its wing feathers go to? I assume it has not been marked by someone.

 Rissa tridactyla.

The São Jacinto Reserve, March 5 - 7

Gullrings at the Eirol landfill, Aveiro (Portugal): March 3, 2014

Today Pedro Moreiro and I visited the Eirol landfill. We searched for rings between 7:15 and 14:15. There were a few short showers spread out over this period, but most of the time it stayed dry. It was also rather windy. There were fewer gulls present than during our previous visit; about 19.000 Lesser Black-backed Gulls, 2000 Black-headed Gulls, 150 Yellow-legged Gulls, one Greater Black-backed Gull and one Mediterranean Gull. We counted 15 Black Kites, which regularly flushed the gulls and by the time of our departure had pretty much claimed the pit, making it difficult to read anymore rings. 41 rings were read. Some of today’s photos:

Adult Black-headed Gull Chroicocephalus ridibundus, from the UK.

Adult Mediterranean Gull Larus melanocephalus

Immature Lesser Black-backed Gull Larus fuscus, from Scotland.

Adult Lesser Black-backed Gull Larus fuscus, from The Netherlands.

 Immature Greater Black-backed Gull Larus marinus.

And now for something completely different?

While walking in Parque da Fontenova in Aveiro (Portugal) on February 25, my I caught a somewhat strange white bird among several Black-headed Gulls that were foraging on the grass. At closer inspection it appeared it was also a Black-headed Gull, but with a colouring defect in its wings (http://observado.org/waarneming/view/81965799). Unfortunately, I wasn’t carrying a camera. Today March 1 the dogs got a walk in the same park and also the gull appeared there again. Coincidentally I ran into Pedro Moreira, who luckily brought his camera with him as he was already on the lookout for this particular bird. Pedro sent me the following photos.

Partially leucistic Black headed Gull Parque da Fontenova in Aveiro, Portugal. March 1, 2013 (photos by Pedro Moreira).

As far as defects in colouring go, this type of deviation seems to occur more regularly among this species. See i.e. http://www.frankmajoor.nl/kokmeeuwen-kleurafwijkingen-1-nl.shtml. Not as completely different as I first thought, but still a beautiful bird to see.

Gulls at the Eirol landfill, Portugal. February 26, 2014.

Due to other obligations and very poor weather conditions, the Eirol landfill had not been visited by me for a long while. Yesterday, there finally was a gap in the clouds. On this trip I got joined by Pedro Moreira. Pedro was particularly interested in the rarities that occasionally show up at the site, but as far as gulls went we did not record anything else then Lesser Black-backed -, Black-headed - and a few Yellow-legged gulls. There were plenty of gulls present; in particular the first two species were abundant. I was hoping to be able to visit the site before the first of this year’s Black Kites showed up, but we quickly found out that they were already there. We made a maximum count of 25 kites, which continuously flushed the gulls. According to personnel the first kites appeared around the 21st of this month. Between 7:15 and 16:45 Pedro and I managed to read 46 rings (44 LBBG and 2 BHG). This number could have been a lot higher if it weren’t for the dirt that covered many (about 40%!) of the rings, as well as for the time we spent talking with personnel of the site, and for the time we watched the impressive interactions between the gulls and the kites, making it a very nice day after all!

Here Fido, bring me the slipper.