Mangroves are increasingly recognized for their role in supporting adaptation to climate change and variability. However, knowledge about how climate change and variability affect mangrove ecosystem services (MES) and their role in supporting coastal communities to adaption is limited in Tanzania. We used participatory rural appraisal methods and field observations to explore local communities’ perceptions of climate change and variability, and ecosystem-based adaptation (EbA) strategies in the mangroves of the Rufiji Delta, Tanzania. Decrease in rainfall, increased temperatures, coastal flooding, and the incidence of sea level rise were identified as key variables associated with a changing climate in the delta. Perceived climatic stresses included damaged fish breeding sites, altered climate regulation and a decrease in coastal protection and flood control. Decline in crop, fish and honey production were perceived as the main impacts on community livelihoods, although there were significant differences across occupational groups. Dependence on MES in times of shocks, such as when agriculture production fails, switching of occupation, crop diversification, fishing in deep waters and migration to other areas provided potential adaptation options. Although the reported perceptions related to climate change or variability are not explicit, they both have negative consequences to mangrove dependent communities’ livelihoods.