Parity Ratio of Males and Females in Broods of the Demoiselle Crane Anthropoides virgo in Kalmykia and Buryatia

The offspring sex ratio of the Demoiselle crane (Anthropoides virgo Linneaus, 1758) was analyzed in two remote breeding groups of the European (Republic of Kalmykia) and Asian (Republic of Buryatia) parts of the range in 2023. Using the molecular genetic marker EE0.6, the sex was determined in 46 chicks (24 males and 22 females) from 30 broods. In the total sample, the deviations from equal proportion of females and males were not significant (0.521, P = 0.092). The sex ratio in each of the studied breeding groups also did not statistically differ from parity, although males (0.650, P = 0.523) prevailed in two-chick broods and in general in the offspring of the Demoiselle crane in Kalmykia (0.423, P = 0.781), while females prevailed in two-chick broods and in general in the offspring of the Demoiselle crane in Buryatia (0.423, P = 0.781). The obtained data support the strategy of reproduction of parity number of both sexes in the Demoiselle crane and may indirectly indicate that in this species the energy cost on raising males and females is equal, and the pressure of environmental conditions is not so strong to cause bias of the existing balance towards either sex.