And Spring Begins!

IC, TC and PML waiting for the right moment to capture the birds. Spring has come a bit rough this year!

Spring has arrived. And so did northward migration and another fieldwork season! For the first capture attempts we used a new and "homemade" woosh net at some high-tide roosts and we managed to capture some dunlins Calidris alpina, sanderlings Calidris alba, ringed plovers Charadrius hiaticula and Kentish plovers Charadrius alexandrinus.

Amongst these we had some recaptures, including two special dunlins captured on the 28th of March at the Brito saltpans: dunlin 3580058, a bird carrying a Swedish ring, and dunlin D018942, which was ringed by some of us at the neighbour Vale Frades saltpans on the 7th of January of 2003! At the moment of capture, this dunlin bird was aged as 5 (Euring code, meaning that the bird was born the previous year), so it is celebrating the 11th anniversary this year! Although impressive, and a really nice recapture information, remember that the longevity record for this species is 28 years and 10 months (see Euring list)!

  

Location of the Brito and Vale de Frades saltpans: two roosts ca. 6 km apart where the same dunlin was captured within 11 years!

 

 

 

 

Dunlin (Calidris alpina) with Swedish ring

TC and CC processing birds at Hortas fieldstation.

 

Expeditions to Banc d'Arguin, Mauritania 

December 2012 and January 2013

The winter 2012/2013 has been a mark in our long-term shorebird projects. In the scope of the new project Invisible Links we started to broaden the geographic borders of our study areas and headed for southern wintering areas within the East-Atlantic Flyway: Mauritania and Morocco.

The Banc d'Arguin stands on the African Atlantic coast, where the ocean and the desert meet. The coastal area comprises shallow coastal areas with extensive mudflats covered by seagrass, small islands, coastal swamps and sand dunes. The Banc d'Arguin is one of the most important areas in the world for migratory waders, holding approximately 2 million birds!

The main goals of the two expeditions were to (1) sample the several components of the trophic web to study its functioning through stable isotope analysis, (2) sample wader toenails to assess their isotopic signatures and describe a characteristic and reference signal for Banc d'Arguin, (3) improve the knowledge on the diet and foraging behaviour of small waders, with particular focus on dunlins and sanderlings.

Sampling invertebrates at Banc d'Arguin

Sorting invertebrate samples at the Iwik field station

 Our expeditions to Banc d'Arguin gave us the opportunity to expand the Dunlin colour-ringing program started in 2008 at the Tagus estuary. The help of the NIOZ team was crucial during night captures. Dunlins were colour ringed with a combination of 3 standard colour rings plus one blue flag ring.

Colour-marked dunlin (Calidris alpina)

January is also time for the annual waterbird count leaded by PNBA (Parc National du Banc d'Arguin). We joined the PNBA staff to the islands of Niroumi and Arel to count thousands of waders that use this islands to rest during high tide.

Integrating the PNBA staff team to perform annual waterbird counts at Banc d'Arguin