MARKING TECHNIQUE OF EMBRYO IN EGG FOR ID ENTIFICATION OF SMALL PASSERINE (PASSERIFORMES) NESTLINGS AFTER HATCHING

A simple technique of marking embryos in eggs for identification of sm all passerine nestlings after hatching is described. The shell of pipp ing eggs of tree and house sparrow were perforated on the pipping open ing and the embryo beaks were. marl;ed with a marker (0,5 mm). Holes i n egg shells were no mole than 2 x 2 mm in size. Red, green, blue and black waterproof ink was used, The portion of the identified nestlings within the experimental broods amounted to 76% (tree sparrows) and 91 % (house sparrows). Hatching mortality in control and in experimental clutches did not differ significantly.