Monday, May 16, 2011

The Irish Flamingo

Little Grebe, Tachybaptus ruficollis
Of the four species of grebe regularly found in Ireland, the Little Grebe (Tachybaptus ruficollis) is the smallest. Little Grebes are found throughout the world, with the European population numbering > 99,000 breeding pairs, of which 1,000-2,500 are found in Ireland (1). A brownish bird, with chestnut cheeks and a lime green spot at the base of the bill in the breeding season (2), they nest in shallow waters of ponds, canals and slow moving rivers. This propensity for shallow waters is due to their feeding habits. As divers, the longer they spend under water, the longer their recovery time (3). This makes smaller water columns more attractive to them as they feed on a variety of arthropods, molluscs and even small fish and tadpoles. Study of the Little Grebe is often problematic due to its secretive nature (4), however it is known that harsh winters affect populations due to reduced feeding oppertunitites when open water sources freeze.
Little Grebe, Tachybaptus ruficollis
The grebes as a family (Podicipedidae) are the only members of the order Podicipediformes, and at first glance these small, diving birds bare little resemblance to the tall, filter feeding flamingo family, Phoenicopteridae. Yet recent analysis of mitochondrial and nuclear DNA from both families (5), as well as cladistic analysis of morphological characteristics (6) showed that the two are sister clades. This points to flamingos evolving, not from a shore like ancestor, but from a highly aquatic one. It also interestingly shows the evolution of two very different feeding strategies (foot propelled diving versus filter feeding) in birds.

  1. BirdLife International, 2011. Species factsheet: Tachybaptus ruficollis
  2. Sterry, 2004. Collins Complete Guide to Irish Wildlife p. 32
  3. Fox, 1994. Bird Study 41 pp. 15-24
  4. Moss and Moss, 1993. Bird Study 40 pp. 107-114
  5. van Tuinen et al., 2001. Proceedings of the Royal Society of London B 268 pp.1345–1350
  6. Mayr, 2004. Zoological Journal of the Linnean Society 140 pp. 157–169

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