Abstract: It is the genetic variation and structure of population that as the basis to determine the level and the unit of protection. In this research, source of DNA was sampled from faeces of the black-necked crane and common crane. We did the amplification of COI gene of the two cranes, then we analyzed the genetic variance of COI sequences combined with same genes from GenBank. The results showed that COI gene variants in the population of these two cranes are very small, almost zero, so we suggest to strengthen the protection of them. Alternatively, by the analysis of mutation loci ratio for each gene in the mitochondrial genome of black-necked crane and common crane, we found that proportion of mutation loci in CR and Cytb is higher than in other genes. Thus, we considered these four genes are the optimal molecular markers in the population genetics studies of black-necked crane and common crane. These results will provide the basis for the establishment of scientific protection strategy and lay the foundation for the molecular phylogeny and molecular molecular scatology of these two cranes.

Key words: black-necked crane, common crane, genetic diversity, COI, mitochondrial genome