Genetic Sexing of the African Penguin, <scp> <i>Spheniscus demersus</i> </scp> Using Noninvasive Guano and Molted Feather Samples

The monitoring of sex ratios in wild populations of the critically endangered African penguin <i>Spheniscus demersus</i> 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 <i>S. demersus</i> 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 <i>S. demersus</i> populations through sex determination using noninvasive means.