Contemporary Management of Human‐Caused Hybridization in Mammals: A Review

ABSTRACT Introduction Anthropogenic hybridization (AH) is increasingly recognized as a conservation issue, as human activities facilitate interbreeding between previously isolated mammalian taxa, potentially threatening genetic integrity and population viability. Aims We synthesize current knowledge on AH in mammals, with the aim to fill a knowledge gap on how to address AH and assess the feasibility of management interventions. This review intends to consolidate available knowledge on several aspects concerning AH in mammals, from its occurrence across species and regions to its main human‐derived drivers and its effective management. Methods We reviewed peer‐reviewed articles, books, dissertations, grey literature, and official documents using Google Scholar, Scopus, and Web of Science. We screened results by title, abstract, and full text, and used a snowball approach to identify additional studies, analysing ecological drivers, taxonomic and geographic patterns, hybrid detection methods, management strategies, and social dimensions. Results Acknowledging that some cases of management interventions might have been underreported in the scientific literature, and that some might have been published in non‐English sources, we reviewed a total of 289 case studies (1978–2024). AH was documented across 101 mammal species worldwide, predominantly in terrestrial systems and in the orders Carnivora and Cetartiodactyla. The main drivers included free‐ranging domestic animals, low population densities, and translocations. Discussion Where implemented, management responses were highly heterogeneous and often lacked structured frameworks, clear objectives, or population‐level assessments. Three main management interventions have been identified: preventive, proactive, and reactive responses. These approaches were used to address escalating levels of hybridization and were often used in combination. Reactive approaches, particularly removal of admixed individuals was common, though constrained by uncertainty in hybrid identification and social acceptability. Assessment of the effectiveness of management interventions through dedicated monitoring, which would be the ideal approach, has rarely been reported. Accordingly, the modification of management actions following monitoring (i.e., adaptive management), was not widespread. Few of the management‐oriented case studies relied on social engagement and support, underscoring how applicability and sustainability of management actions were markedly affected by the social perception and reaction to management. Conclusion Our findings reveal a substantial gap between knowledge and implementation. Accordingly, we provide recommendations for future AH management, including: (1) the necessity of informative genetic markers with sufficient discriminatory power for the study system to reliably identify admixed individuals, as well as the adoption of formal surveys and analytical techniques; (2) the establishment of clear management goals and, accordingly, the choice of effective and socially acceptable adaptive management strategies, including a combination of preventive, proactive, and reactive approaches; (3) the enhancement of public awareness of AH through clear, accurate, and carefully framed communication and the fostering of stakeholder participation in management to facilitate conflict resolution; and (4) the adoption of focused monitoring to assess the effect of AH through standardized approaches to detect admixed individuals and monitor AH dynamics at the population level.