Thursday, March 20, 2014

Latest peregrine nest box in Zwolle (The Netherlands) gets occupied!

Recently I devoted a blog entry to the developments of the Peregrine Falcon Falco peregrinus population of Zwolle, The Netherlands. On February 18, 2014, I helped Jan van Dijk (Raptor Workinggroup Zwolle) with installing a new nest box on a transmission tower in the north of the city, where a potential breeding pair has been observed for about a year now ( Jan informed us the birds already accepted the box (and not the top of the tower's staircase) and that there is a lot more going on with the Peregrines in Zwolle:

Incubating adult female Peregrine falcon in the new nest box in the north of Zwolle (photo: Jan van Dijk).

Saturday, March 15, 2014

Picking up Puffins on the first beached bird and mammal survey between Sao Jacinto and Torreira

On March 14 2014, a survey of beached birds and mammals was conducted along a 10 km long transect between Sao Jacinto and Torreira, by Pedro Moreira and me. The transect included 5 km of closed off beach belonging to the Sao Jacinto reserve, who gave us permission for this survey. The idea was to get an impression of what species and their numbers had been washing up on the beach along the northwestern coastline of Portugal during the previous months. None of this 10 km of beach gets regularly cleaned, making it a very suitable length of coastline for this study.

Another motivation for this activity had been the reports of large numbers of dead seabirds that washed up on beaches in France and Spain, after the ‘wreck’ that occurred earlier in the year in the Bay of Biscay due to continuing bad weather conditions (See and

 The 10 km transect we walked from Sao Jacinto to Torreira.


Which of these birds died in the wreck that occurred in the beginning of the year remains difficult to determine, with the absence of earlier survey results. We suspect this had been the case with all of the puffins that were found. Even the few of those that we found on the recent tide lines showed signs these had been floating in the ocean for a while. All of the Lesser Black-backed Gulls had died recently and these were probably all local birds. Also the Common Guillemot and one or two Razorbills appeared a bit too fresh to have come all the way from the Bay of Biscay.

Beached Atlantic Puffins.

 Three Lesser Black-backed Gulls and two Razorbills.

 Great Northern Loon.

Unidentified Seahorse...

...and a coconut.

Wednesday, March 12, 2014

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: 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).

Sunday, March 9, 2014

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.


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.