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Overhunting is a pervasive threat for mammal communities around the globe. The loss of these mammal populations also mean the loss of their interactions, both mutualistic and antagonistic, with plant communities. An important question is what consequences the loss of mutualistic or antagonistic interactions will have for the success of individual plant species. Many plant species have complex life-cycles with multiple life-stages, where they depend on vertebrate frugivores for dispersal of seeds but are simultaneously limited by seed predators, herbivores and other natural enemies at other life stages. It is both unknown, and challenging to predict, how the deterioration of these relations will interact across the life-cycle of plants and influence plant abundance. Here we propose a simple theoretical framework which predicts how multiple life-stages and vital rates determine plant abundance through their influence on two key statistics: low-density population growth rates (the ‘invasion growth rate’) and strength of density-dependent population growth (‘stabilization’). The model predicts that hunting will increase plant abundance through lack of dispersal, unless this is compensated by increased density-dependent regulation. We then continue to test our framework in a case study on a well-studied, mammal-dispersed palm species, Attalea butyracea. In the case study, we quantify the full life-cycle of this palm along a gradient of population abundances in a hunted and a protected forest. We show that loss of dispersal services increases low-density population growth rates within local populations, and that negative density-dependent enemy …