Breeding biology of isolated captive Dalmatian Pelicans (Pelecanus crispus) at the Shanghai Zoo, China

Abstract The breeding biology of a captive, isolated population of Dalmatian Pelicans (Pelecanus crispus) at the Shanghai Zoo, China, was studied from 2007 to 2019. The breeding age of the Dalmatian Pelicans was estimated at three to four years old, and they started breeding in late October or early November. The clutch size varied between one and two eggs per nest, and the eggs were 83.2 ± 4.8 mm in length, 55.6 ± 2.9 mm in breadth and 136.1 ± 21.5 g in weight. The fertility fluctuated slightly, with an average rate of 38.7 ± 9.7%, but remained consistently low. The survival rate of chicks fluctuated substantially from 0–100%, with an average survival rate of 68.6 ± 27.6%. The averaged values of observed heterozygosity, expected heterozygosity and polymorphism information content were 0.468, 0.465 and 0.446, respectively. It indicated that the population had a low heterozygosity and genetic diversity. There was a significant change in the breeding index compared to that recorded 40 years ago, which indicates that inbreeding depression has occurred in this small, isolated, captive population of Dalmatian Pelicans.