Can greater flamingo recognize fertile vs. unfertile egg? A single case study

Flamingos are colonial birds and in zoos are best kept in flocks of at least 20 birds. However reliable breeding occurs with flocks of more than 40 birds. Fertility of captive flamingos varies between different flocks, species and seasons. Knowing the reproductive history of each individual flamingo allows anticipating fertility/infertility in eggs and makes informed decisions as to whether to pull, allow recycling, substitute a dummy, or allow continued incubation. Infertile eggs (or the dummy eggs on the parents' nest) can be removed to encourage birds to relay. Pairs producing infertile first eggs will often produce fertile second eggs. Flamingos appear to be unable to recognize their own egg and will incubate any object roughly the correct size and shape. This study investigated the behaviours of the male and the female of a pair of Greater flamingos’ colony housed at Parco Natura Viva in order to detect their ability to recognise fertile and unfertile eggs. The behaviours of the male and the female of the pair were collected over the first period of incubation - the unfertile egg - and the second period of incubation – the fertile egg. Results of this study underline that the female performed different behaviours between the infertile egg incubation period and the fertile egg incubation period; whereas no behavioural differences of the male were found between the two periods. These findings seem to highlight that flamingos might be able to detect infertile eggs, especially the female of the pair. The results of this study can make a difference in the care and management of captive colony of Greater flamingos. However, further researches are needed to observe the behaviour of greater flamingos in order to determine behavioural differences between fertile and unfertile eggs.