Molecular analyses
Total genomic DNA was extracted using the QIAamp 96 DNA QIAcube HT Kit
and the QIAcube DNA extraction robot (QIAGEN, Hilden, Germany) following
the manufacturer’s protocol with modification as described in Dolfo et
al. (2023). Samples were genotyped at 23 microsatellite loci using five
multiplex reactions as per Dolfo et al. (2023) (GenBank accession
number: OQ162049-OQ162073). Allele sizes were visually assessed using
GENEMAPPER software v.5 (Applied Biosystems). All ambiguous peak
profiles were considered as missing data and only individuals with
missing data which occurred at 3 loci or less were kept for the
analyses. MICROCHECKER v.2.2.3 (Van Oosterhout et al., 2004) was used to
identify null alleles, stuttering errors, and large allele dropout. In
total, 1592 hatchling and female genotypes were kept for further
analyses.