Abstract
Abstract
Ambergris, a rare and valuable by-product of sperm whales, is prized for its distinctive fragrance and may offer insights into whale metabolism and diet. However, identifying ambergris, particularly when recovered as jetsam, is challenging owing to sample heterogeneity and the effects of environmental weathering. Traditional identification techniques, including visual inspection, odour analysis and chemical profiling (e.g. gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy), can confirm chemical composition, but cannot determine biological origin. DNA metabarcoding presents a complementary approach for verifying ambergris by detecting species-specific DNA, such as DNA from Physeter macrocephalus, in environmental samples. This study assessed the effectiveness of DNA metabarcoding alongside chemical profiling by analysing curated ambergris specimens from the Western Australian Museum. DNA concentrations varied across samples, with several yielding P. macrocephalus DNA, confirming their origin. However, some samples lacked detectable DNA, probably owing to degradation or possible misidentification. Chemical analysis identified key biomarkers, such as ambrein, in most samples, supporting their classification as ambergris. The findings highlight the value of combining DNA metabarcoding with traditional chemical methods to improve the reliability of ambergris identification.