Ardea Official journal of the Netherlands Ornithologists' Union |
Giannangeli L., de Sanctis A., Manginelli R. & Medina F.M. (2004) Seasonal variation of the diet of the Stone Curlew Burhinus oedicnemus distinctus at the island of La Palma, Canary Islands. ARDEA 92 (2): 175-184 |
In this study we describe seasonal variation in the diet of the Stone Curlew Burhinus oedicnemus distinctus at La Palma, one of the Western Islands of the Canary Archipelago. The study was conducted through faecal analysis. Faeces were collected bimonthly and 266 faeces were examined. The Stone Curlew foraged on 18 main food categories. The diet was clearly dominated by millipedes, which represented the major part of the faeces content in all sampled periods. Beetles were the second most frequently occurring invertebrate group with ground beetles the most dominant among the families present. Grasshoppers and hymenoptera were the other main preys groups consumed by the Stone Curlew. Animal prey such as molluscs and mammals were less frequently found in faeces. The importance of plant material increased sharply between late winter to a peak in the March-April samples. The Stone Curlew has a fairly constant niche breadth, which is suggested by the values of the Levins Index for the different sampling periods. The calculated values of the Pianka Index indicated a very high degree of dietary overlap between periods. Our data confirmed that this species is strictly a surface feeder and that a low intensity farming system may be required to conserve this species. |