This study draws on the local ecological knowledge of 58 hunters from seven communes in the Ngoc Son Ngo Luong Nature Reserve (Hoa Binh province, North Vietnam) to examine the local status of 40 threatened vertebrates. The reserve forms part of a biodiversity-rich mountainous corridor. Respondents were shown photographs of the species and asked to rate their abundance on a scale of 0–3 (0, extinct; 3, very abundant) in two periods: pre-1975 (before Doi Moi) and in 2009. The results show that 39 species have lived in the area and five are now extinct (Delacour's langur Trachypithecus delacouri, northern white-cheeked crested gibbon Nomascus leucogenys, dhole Cuon alpinus, oriental small-clawed otter Aonyx cinereus, Indochinese tiger Panthera tigris corbetti) and the presence of another six is doubtful (Phayre's leaf-monkey Trachypithecus phayrei ssp. crepuscula, sun bear Helarctos malayanus, binturong Arctictis binturong, fishing cat Prionailurus viverrinus, leopard Panthera pardus, wreathed hornbill Anorrhinus undulatus). The results show a general decline in numbers and abundance, with mammals declining fastest, especially carnivores and primates. The differences in abundance between species have narrowed since 1975, converging towards trends of general impoverishment at similar low abundances. The survey results were similar among communes and also concord with the findings of research in nearby areas. This study demonstrates the usefulness of local ecological knowledge for planning, decision-making and management of protected areas in the absence of historical records or financial resources for conducting intensive fieldwork in remote and little-known areas.