02900nas a2200277   4500008004100000245021900041210006900260260001200329300001200341490000700353520188600360653000902246653001602255653003002271653002102301653002102322653001102343653001702354653002402371653002602395100002002421700001602441700001802457700001402475856013302489       1997                        eng d00aComparative nest site selection and breeding success in 2 sympatric ardeids, Black-crowned Night-Heron (<i>Nycticorax nycticorax</i>) and Little Egret (<i>Egretta garzetta</i>) in the Axios Delta, Macedonia, Greece0 aComparative nest site selection and breeding success in 2 sympat  c1997///  a505-5170 v203 aWe studied nest site selection and breeding success of Black-crowned Night-Herons (Nycticorax nycticorax) and Little Egrets (Egretta garzetta) in the Axios Delta (Greece) from 1988 to 1990. Both species nested above the middle of tamarisks and alders. Nest density varied each year from 333.3 nests/ha to 646.2 nests/ha for Blackcrowned Night-Herons and 291.7 nests/ha to 421.5 nests/ha for Little Egrets. Black-crowned Night-Herons started to breed earlier than Little Egrets, also placing their nests higher (mean nest height: 4.21 ± SD of 0.80 m and 3.54 ± SD of 0.71 m for Black-crowned Night-Herons and Little Egrets, respectively). The nearest neighbors were conspecifics for Black-crowned Night-Herons and heterospecifics (Black-crowned Night-Herons) for Little Egrets. The mean distance of the nearest neighbor was similar in both species (1.02 ± SD of 0.46 m and 1.11 ± SD of 0.37 m for Black-crowned Night-Herons and Little Egrets, respectively). In contrast to late-nesting Little Egrets that located their nests lower, Black-crowned Night-Herons maintained a constant nest distance from the ground. The mean clutch size (3.40 ± SD of 0.60 and 4.32 ± SD of 0.81 for Black-crowned Night-Herons and Little Egrets, respectively) and the mean chick survival per nest (2.48 ± SD of 0.95 and 2.53 ± SD of 1.28 for Black-crowned Night-Herons and Little Egrets, respectively) of both species varied among the study years. No variation was observed in the means of clutch size and chick survival per nest of Black-crowned Night-Herons among the 3 sub-periods of the breeding season. Little Egret clutch size and mean number of eggs hatched was smaller in late nesters, but no difference was observed in chick survival per nest between early and late nesters. Nest placement did not affect chick survival in Black-crowned Night-Herons and only marginally in Little Egrets.10aAves10aAxios Delta10aBlack-crowned Night-Heron10aBreeding success10aEgretta garzetta10aGreece10aLittle Egret10aNest site selection10aNycticorax nycticorax1 aKazantzidis, S.1 aGoutner, V.1 aPyrovetsi, M.1 aSinis, A.  uhttps://icgf.myspecies.info/content/comparative-nest-site-selection-and-breeding-success-2-sympatric-ardeids-black-crowned-night