Genetic Sexing of the African Penguin, Spheniscus demersus Using Noninvasive Guano and Molted Feather Samples

The monitoring of sex ratios in wild populations of the critically endangered African penguin Spheniscus demersus is essential for conservation management but is currently limited by the inherent difficulty in acquiring blood samples required for sexing. This study optimized a noninvasive method for the DNA extraction and PCR-based genetic sexing of S. demersus using guano and molted feather samples. Two primer sets (CHD1F/R & 2550F/2718R) were used that target sex-specific length polymorphisms in the CHD1-Z and CHD1-W genes on the CHD1 sex chromosomes. Using methods optimized for the extraction of DNA from inhibitor-rich guano and difficult-to-lyse molted feather samples, this work can directly contribute to the conservation monitoring of wild S. demersus populations through sex determination using noninvasive means.