Inconsistent pattern of extra pair paternity in first and second broods of the Great T’it Parus major.

In this study we compare extra-pair paternity rates in first and second broods of 25 individual breeding pairs of the Great Tit Parus major. 24% of the first broods contained at least one nestling due to copulations outside the pair bond in contrast to 60% for second broods . The average proportion of extra-pair young per brood equalled 3 .9