TERRITORIAL CONFLICTS IN MALES OF THE DRAGONFLY, ORTHETRUM-JAPONICUM-JAPONICUM (ODONATA, LIBELLULIDAE) - THE ROLE OF BODY-SIZE

The relationship between body size and the results of territorial conf licts was studied in males of the dragonfly, Orthetrum japonicum japon icum. Territorial residents were larger than intruders in body width, but not in hind wing length. Winners of territorial conflicts were lar ger than losers in body width, but not in hind wing length. This diffe rence was attributed to the fact that residents were larger than intru ders. The results of territorial conflicts were more strongly affected by the role of the opponents (resident or intruder) than by the diffe rence in their body sizes. Territorial males arrived at the territoria l sites earlier than nonterritorial ones on a given day. The body size of males arriving al the study area earlier in a day was not larger t han that of males arriving later.