The Courtship and Copulation of the Greenfinch (Chloris Chloris)

I. Observations were made on the reproductive behaviour of 13 pairs of captive Greenfinches. 2. The various behaviour patterns used in courtship and copulation are described and analysed. In nearly every case it can be shown that each pattern is associated with a particular combination of strengths (and relative strengths) of tendencies to attack, flee from and behave sexually towards the mate. 3 In order for copulation to be successful, the tendency to behave sexually must be sufficiently strong to inhibit the tendencies to attack and to flee from the mate. 4. The sequences of behaviour patterns involved in successful and abortive copulation attempts are traced. Much of the variability of these sequences is associated with individual peculiarities in the pairs of birds concerned. 5. The male is dominant to the female in winter but becomes subordinate as the reproductive season advances. The female's dominance later in the season is, however, often broken by outbursts of the display by the male, which has a strong aggressive component. 6. This sleeked wings-raised display becomes very much less frequent just before copulation starts. Once copulatory behaviour is being shown aggressiveness is almost entirely suppressed and each sex is under the influence of conflicting tendencies to flee from and approach the mate. 7. The seasonal increase in the tendency to behave sexually is thus associated first with a suppression of aggressiveness and later with a suppression of the tendency to flee from the mate. During much of the breeding season aggressiveness is suppressed for most of the time, but appears in the form of the display at times when the aggressive factors are temporarily high. 8. The most fundamental difference between the displays of the Chaffinch and the Greenfinch seems to be in the extent to which aggressiveness is suppressed. There are, however, many differences between the behaviour of these species.