Genetic Insights Into Human-Driven Hybridization, Cultural Shifts, and Ecological Consequences of Feral Pigs (Sus scrofa) in Hawai‘i

Abstract

Feral pigs (Sus scrofa) in Hawai‘i pose a persistent threat to native biodiversity, endemic species, and culturally important resources. Polynesian pigs, or pua‘a, were brought to the Hawaiian Islands with Polynesian settlement in the mid-1200s and represent part of the cultural legacy of Hawai‘i. Since the introduction of European pigs in 1778 and onward, the ancestral composition of contemporary animals has been debated, and conservation efforts for island endemic species have been challenged by tension between ecological destruction caused by contemporary feral pigs and the cultural importance of this animal. To inform this complex issue, our objective was to evaluate the genetic ancestry of contemporary feral pig populations across Hawai‘i to elucidate genetic remnants of past introductions. We used a high-resolution single nucleotide polymorphism (SNP) array, providing a survey of the entire genome, to characterize ancestry, including hybridization of Polynesian pigs with global Asian and European lineages. We assembled a comprehensive reference set—representing the S. scrofa wild–domestic species complex—from which we queried 608 Hawaiian feral pig samples to quantify ancestral composition. Our results demonstrate that contemporary Hawaiian feral pigs have admixed ancestry influenced by European Heritage breeds and animals of Asian origin—potentially descending from initial Polynesian introductions. Importantly, we establish that European domestic lineages represent the dominant ancestral influence among contemporary feral pigs in Hawai‘i, which challenges previous claims of genetic uniqueness of these populations within the broader S. scrofa wild–domestic species complex.

Citation

Mangan, A. M., Smyser, T. J., Barca, N., Hess, S. C., Kinney, K. M., Phelps, D., ... & Piaggio, A. J. (2026). Genetic Insights Into Human‐Driven Hybridization, Cultural Shifts, and Ecological Consequences of Feral Pigs (Sus scrofa) in Hawai ‘i. Ecology and Evolution, 16(1), e72822.