Black-necked Grebe round-up

Every year, thousands of Black-necked Grebes migrate south from their breeding grounds in the Arctic tundra to moult and spend the winter in the south of Europe. There is a particular concentration that favours the salt pans (salins) near Huelva in Andalusia. They feed mainly on the larvae of aquatic insects.

Here, there is a long-term research study in which samples of the grebes are captured during the moulting period (when flying is weakest) for ringing and measurement. I was fortunate to be invited to participate in one of the capture events.

The salt pans are also the home of thousands of Greater Flamingos (this individual is flying from right to left)

The Black-necked Grebes swim off looking suspicious... they have seen this all before!

The Expedition of about 50 participants assembles

The nets are prepared...

...and the Director, Luís García, explains the strategy with a stick in the sand.

Then it is into the water where the team pushes the net forward through the brine...

...corralling the grebes int a smaller and smaller area...

..until they are so concentrated they can be plucked from the water like fish.

The grebes are not web-footed (like ducks) but have these lobed feet as an adaptation for swimming and diving

Groups of grebes are transported to the processing station where...

...they are kept in holding pens until...

...it is time for each to be ringed and measured in turn.

The Director photographs the extended wing of every bird to keep a record of moult progress.

A final look at these delightful water birds before...

...release when they scamper of towards the middle of the lake.

A total of 242 Black-necked Grebes was processed that day. The Director joins the group for a few beers after a hot, and very salty, day's work.