The response of 1090 great tits (Parus major) to a stuffed (Accipiter nisus) near their nest were observed. 320 out of 450 male tits responded agressivly, from female tits 420 exhibit aggressive behaviour.

1. How significant (numerically) is this difference for conclusion that male and female tits in general reveal different agressiveness to a stuffed (Accipiter nisus) .
2. Is this evidence enough for science ?
3. How to obtain more reliable observation results?

You shold make a 2 x 2 condingency table before using chi squared test because the ferquency of negative answers is directly not mentioned in the exercise text.
Chi squared test in the SDC.