We compared the overall mating rates of the morphs, morph-differences in resistance towards mating attempts and the effects of realized matings and mating attempts on female fecundity.
We chose two simple behavioral variables known to be affected by OSR in water striders (Rowe 1992; Krupa and Sih 1993; Jablonski and Vepsalainen 1995; Vepsalainen and Savolainen 1995): the female resistance to mating attempts and the copulation duration.
Moreover, it is unlikely that the cue for queens to cease mating attempts and initiate egg-laying is related to the number of mating flights taken, because half of our observed queens initiated egg-laying after a single mating flight while the other half did not.
Ink was released under three different agonistic conditions: female-female aggression, rejection of mating attempt, and when attacked by a predator.
The overall positive relationship between realized matings and mating attempts indicates that morph-specific copulation frequencies in the field do, to some extent, reflect the total number of previous male mating attempts (Fig 3).
However, both tolerance and resistance towards male mating attempts and realized matings are likely to be costly, which is indicated by the fact that androchromes have a lower overall fecundity than infuscans females [24].
For time, visits, and mating attempts, female identity was included as a random effect (repeated measures analysis), which was not necessary for the female-averaged responses of affiliation and aggression.
However, females are capable of refusing mating attempts and it does not appear to be possible for males to force female to mate (Cant 2000).
Instead, the display of precopulatory aggression indicates resistance of the female to male mating attempts and female urine release occurs as an integral component of aggressive behaviour [ 26].
Support for this comes from behavioural studies showing that when androchrome females are approached by a male, they respond more aggressively towards mating attempts than gynochrome females [ 6, 40] and are more reluctant to engage in multiple matings [ 41].
