The cave site of Lachitu (RIQ) on the Vanimo coast of New Guinea preserves a large faunal assemblage covering the last few centuries to ~30,000 years ago, offering a unique insight into the subsistence strategy of humans in northern New Guinea from the Pleistocene through to contemporary times. Here, I present a summary of results from the analysis of fauna from three excavation squares at Lachitu from the 2004-5 field season. The assemblage reflects a diverse strategy for Lachitu's inhabitants with reliance on both terrestrial, arboreal and marine animal resources at all stages, but with a dramatic increase in the importance of the latter in the Late Holocene. Changing abundances and disappearances of various mammal taxa at Lachitu, many of which are no longer extant in the modern fauna of northern lowland New Guinea, indicate a substantial shift in the environment and game animal resource base available to local hunters occurred during the Holocene.