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Many studies have focused on the colonial behaviour of birds but information on the processes related to the addition of new breeders to colonies is still scarce. The breeding parameters of new, young, breeders in a colony differ from those of experienced breeders initially. Hence, there must be an underlying process to synchronise such parameters of the new additions to the original colony values. To determine how this synchronisation process takes place, we surveyed a White Stork colony in the northern Madrid province (Spain) for five consecutive breeding seasons. Given the high nest site fidelity of this species, we established a relationship between nest age (new or old) and breeding pair age (young breeder or established adult). Newcomers occupy new nests whereas established breeders use old nests. We compared the laying dates at new nests over a 3-4 year period with those at the old nests in the colony to determine whether new breeding pairs were synchronising their laying dates to those of the existing colony. Young breeders require up to three breeding seasons to synchronise their laying dates with those of the established colony. To our knowledge, this is the first time that such a synchronisation process has been described for storks. Nest age should also be considered when analysing breeding parameters that may differ between young and old breeders. —Cabodevilla, X. & Aguirre, J.I. (2019). The nesting synchronisation process of new breeders in a White Stork Ciconia ciconia colony. Ardeola, 66: 279-289.