Sonication as an aid in cleaning cladoceran remains extracted from sediment cores

Ultrasonic treatment (sonication) of the Szczecin Lagoon sediment samples processed for examination of cladoceran remains is described. As opposed to cladoceran remains from non-sonicated sediment, those extracted from the ultrasound-treated samples were clean, easily stained, clearly visible in microscope slides and identifiable. Sonication is therefore recommended as an aid in rendering cladoceran remains free of adhered particles that obscure the specimens and complicate their identification in some sediments.