Friday, 9 December 2016

Spain 2: Greater Flamingo

Greater Flamingo, Ebro Delta
  One of the most instantly recognisable birds in the world is the flamingo. Although usually associated with Africa and the Americas, there is actually quite a reasonable population around the north shores and islands of the Mediterranean, especially in Spain and the south of France.  The species involved is the Greater Flamingo, Phoenicopterus roseus., one of two living species found in the Old World, along with the Lesser Flamingo, Phoeniconais minor, which is almost entirely restricted to Africa. 

Greater Flamingo Flock, Ebro Delta
There are another four species found in the Americas, of which the only one found naturally in North America is the American Flamingo Phoenicopterus ruber. The American Flamingo was formerly classed as a subspecies of Greater Flamingo but has now been split into a separate species. The other three species live in the Andes at high altitudes, and comprise the Chilean, Andean, and Puna or James’ Flamingoes. Very few Andean or Puna flamingos are in animal collections, but some can be seen at the Wildfowl and Wetland Trust collection at Slimbridge.The vast majority of flamingos to be seen in zoos or wildfowl collections are Greater, Chilean, or American flamingos.

In Spain we found a flock of several thousand birds wintering on the Ebro delta. As a result of their specialised habitat, flamingos are at risk of human interference. Disturbance, drainage of lakes, and industrial pollution are probably the main threats. Having said that, around the Mediterranean flamingos will often breed and feed close to human activities, especially salt pans. Typical birds found in similar habitat are Pied Avocet, Black-Winged Stilt, and Slender-billed Gull, which we also found.
Pied Avocet

Black-Winged Stilt
Flamingos are filter feeders, extracting food particles from the water by using their thick, fleshy tongue as a piston to force water through fine plates on the roof of the mouth which trap the food particles. Depending on the gaps between the plates food items may be single-celled blue-green bacteria, or larger shrimps, baby fish, and small molluscs. Different species have different target food items, which is why two species of flamingo can often be found side by side. The Phoenicopterus species feed on larger prey items than the Phoeniconais forms.

Slender-Billed Gull
Whatever their food preferences, the diet of flamingos will contain carotenoid pigments derived from blue-green algae, which are the source of the pink or red in their feathers and skin. Different species have different levels of pigment, and deposit them differently in their feathers, which is why different species may vary from almost white to deep red. Young flamingos have feathers which are white or brown, and take at least a year for the feathers to turn fully pink. The bare parts, especially the legs, can take several years to colour up.

Flamingos are very long lived birds – they have been recorded as living in to their 50’s in captivity and probably often reach at least 30 in the wild. They need a long lifespan as they are not very productive – they only lay a single egg at a time and probably in the wild only raise a youngster to independence perhaps one year in three. They are of course famously social – colonies can reach many tens of thousands of birds in the Rift Valley.

Flamingos have been kept in waterfowl collections for many years, and it is not unknown for them to escape. They may survive in the wild for many years, but a group of escaped Chilean flamingos in Germany some years ago actually began breeding in the wild, and still probably survive. These birds may have been the source of two birds which showed up at Cley in Norfolk in 2010. Some years ago a pair stayed with the swans at Abbotsbury in the South West UK, and even built a nest as I recall being told, but did not succeed in raising a chick. 

(Images my own, close ups from wikipedia)

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