The Effect of Clutch Size on Egg and Hatchling Mass and Measurements in the Common Coot Fulica atra

Ali UZUN, Belgin UZUN, Grzegorz KOPIJ

Ekoloji, 2010, Issue 74, Pages: 160-163



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Studies were conducted in 2008 on Poyrazlar Lake, located in NW Turkey. The clutch size of the Common Coot Fulica atra varied from 3 to 14. The mean clutch size was 6.6±0.34 (N=23 clutches). The clutch size increased with the increase of nest distance from the edge of the Lake. As the clutch size increased, the average egg mass decreased. With the increase of clutch size, the egg diameter and egg perimeter slightly increased but, there was no correlation between these parameters. Out o f 66 marked and measured eggs, 54 (81.8%) hatched, 5 (7.6%) were unfertile, and 7 (10.6%) were lost. There was a positive correlation between the egg mass and hatchling mass, hatchling length, beak length, and leg length.


Breeding biology, clutch size, common coot, hatching success, Poyrazlar Lake


  • Bezzel E (1967) Uber Gelegegrosse und Legebeginn beim Blasshuhn (Fulica atra). Anzeiger der Ornithologischen Gesellschaft in Bayern 8, 183-185.
  • Brinkhof MVG, Cave AJ, Hoge FJ and Verhulst S (1993) Timing o f reproduction and fleding success in the Coot Fulica atrai; Evidence for a causal relationship. Journal of Animal Ecology 62, 577-587.
  • Cichon M (1997) Egg weight variation in the Collared Flycatchers Ficedula albicollis. Ornis Fennica 74, 141-147.
  • Enemar A (1997) The egg size variation of the Treecreeper Certhia familiaris in south-western Sweden. Ornis Svecica 7, 107-120.
  • Humphrey QPC, Wingfield D, Gibbons DW, Magrath RD (1993) Seasonal changes in clutch size in British birds. Journal of Animal Ecolog 62, 263-273.
  • Jankowski W (1983) Wstepne wyniki badan nad ekologia rozrodu lyski (Fulica atra) na Stawach Milickich. Dolina Baryczy 2, 29-44.
  • Kopij G (1997) Timing of colony occupation, clutch size and breeding success in the Cattle Egret Bubulcus ibis related to nest location in a South African heronry. Acta Ornitologica 32, 169-174.
  • Kopij G (1998) Breeding ecology of the Southern Bald Ibis (Geronticus calvus) in the Free State, South Africa. Acta Ornitologica 33, 99-111.
  • Kopij G (1999a) Breeding success in the cattle egret related to clutch size. South African Journal of Wildlife Research 29, 112.
  • Kopij G (1999b) Breeding ecology of the Sacred Ibis Threskiornis aethiopicus in the Free state, South Africa. South African Journal of Wildlife Research 29, 25-30.
  • Kopij G (2004) Breeding density of Fiscal Shrike (Lanius collaris). Biological Letters 41, 77-85.
  • Kopij G, De Swardt DH (1998) Breeding biology of the Little Swift Apus affinis in Bloemfontein, South Africa. Navorsinge van die Nasionale Museum Bloemfontein 14, 145-159.
  • Ojanen M, Orell M, Vaisanen RA (1978) Egg and clutch size in four passerine species in northern Finland. Ornis Fennica 55, 60-68.
  • Samraoui F and Samraoui B (2007) The Reproductive ecology o f the Common Coot (Fulica atra) in the Hauts Plateaux, Northeast Algeria. Waterbirds 30, 1, 133-139.
  • Uzun A, Uzun B, Kopij G (2008) Year-to-year variation in clutch size and breeding success of the Little Egret, Egretta garzetta Linnaeus, 1766, in Turkey. Zoology in the Middle East 45, 35-40.