We obtained 1,997 mite specimens of 49 mesostigmatid species from 50 birds’ nests situated on the water ( Cygnus olor , Emberiza schoeniclus , Fulica atra , Ixobrychus minutus , Locustella luscinioides , Podiceps cristatus , Porzana parva , and Tachybaptus ruficollis ) in 8 study sites of southern Slovakia. The hygrophilous free-living ascids Lasioseius confusus (47.27%), Leioseius minusculus (18.93%) and Cheiroseius cassiteridium (7.51%) were eudominant species. Parasitic haematophagous mites formed neglected portion of the mite material only. These nests are usually destroyed very quickly and the richest nidofauna is present at the end of vegetation period .