Local ecological knowledge provides novel, detailed and context-specific information about human and non-human use of marine ecosystems, therefore incorporating this knowledge into marine conservation planning is crucial. Participatory mapping offers an opportunity to include local knowledge in spatial planning for natural resource management. However, local knowledge presents certain challenges in the form of data inconsistencies, fuzziness and inability to disaggregate different types and formats of knowledge. Using the case of fisheries in southern Maharashtra state, India, I demonstrate how local ecological knowledge may be used to improve the understanding of data-poor fisheries. In the context of fisheries that are globally recognised as lacking management, I examine how local ecological and spatial knowledge about species and fishing practices can be used to fill fine-scale management gaps that do not account for context-specific habitat use. I also explore how fishers'spatial knowledge is intertwined with other forms of local knowledge. The participatory mapping exercise demonstrates that although fishing communities do not profess to be interested in threatened marine species conservation, their spatial and customary fishing practices potentially align with conservation goals. Clear synergies between livelihoods and marine conservation emerge when using local ecological knowledge along with participatory mapping. This research demonstrates that successful fisheries management and marine conservation planning is possible using existing social, cultural practices, translated through geographic tools.