The diet of the Dipper Cinclus cinclus as represented by faecal and regurgitate pellets: A comparison

The diet of the Dipper Cinclus cinclus was assessed by analysis of faecal and regurgitate pellets at six sites in southwest Ireland during the winter, summer and autumn of 1991 and 1992. In total 210 faecal and 210 regurgitate pellets were collected, containing the remains of 1648 and 1655 prey items, respectively. There was no significant difference in the taxonomic composition of the diet as represented by the two pellet types, i.e. no taxon was under- or over-represented in either pellet type. There were few differences between prey sizes in the faecal and regurgitate pellets from the same site and sampling time. Where significant differences were found, the absolute difference between the medians was small and it was the faecal sample which had the larger median prey size. There was no evidence that Dippers use regurgitates to eject the remains of large prey.