Data from: The diet of an endemic subspecies of the Eurasian Spoonbill Platalea leucorodia balsaci, breeding at the Banc d’Arguin, Mauritania

In the period 1998–2010 the endemic subspecies of the Eurasian Spoonbill Platalea leucorodia balsaci breeding in Mauritania has decreased in numbers considerably. The causes for this decline are unknown. This study aimed to investigate the diet of the species. We analysed faecal material collected in the breeding colonies in 8 different years. The results show that Mauritanian Spoonbills almost exclusively eat shrimp (59.7%) and small fish (35.4%), the latter being dominated by Gobiidae (20.8%), Soleidae (4.8%) and Mugilidae (2.8%). Another 10 fish families were represented in small proportions. Shrimp were quantified on the basis of (parts of) mandibles present in the samples. All prey items eaten by the Spoonbills were extremely small. Diet composition of adult birds and chicks appeared to be similar. There was great variation in diet composition of adults between years, but there was no trend in any of the major diet components over the study period. This indicates that the decline of the Spoonbill population is not correlated with changes in food composition. Our diet study has been of a qualitative nature. Considering the dramatic population decline we plea for a more detailed ecological study of the species, including a quantitative approach of food intake and foraging conditions.

1998年至2010年间，在毛里塔尼亚繁殖的欧亚琵鹭（Eurasian Spoonbill）特有亚种白琵鹭毛里塔尼亚亚种（Platalea leucorodia balsaci）种群数量显著下降，目前该种群衰退的原因尚不明确。本研究旨在探明该物种的食性组成。我们对8个不同年份采集自繁殖聚居地的粪便样本开展了分析。结果表明，毛里塔尼亚琵鹭的食物几乎仅包含虾类（占比59.7%）与小型鱼类（占比35.4%）；其中小型鱼类以鰕虎鱼科（Gobiidae，20.8%）、鳎科（Soleidae，4.8%）以及鲻科（Mugilidae，2.8%）占主导。另有10个鱼类科类群仅占极小比例。虾类的定量统计基于样本中留存的颚骨（及其碎片）完成。琵鹭捕食的所有猎物体型均极小。成鸟与雏鸟的食性组成相似。不同年份间成鸟的食性组成存在较大差异，但研究周期内各主要食物类群的占比均未呈现明确的变化趋势。这说明琵鹭种群的衰退与食物组成的变化并无关联。本次食性研究仅为定性研究。鉴于该种群的大幅衰退，我们呼吁对该物种开展更为深入细致的生态学研究，包括对食物摄入量与觅食条件的定量分析。