The amount (composition) and spatial arrangement (configuration) of forest patches in fragmented landscapes influence the accessibility, as well as the abundance and diversity of resources available to bats. Moreover, tropical fruit and insect abundance differ seasonally in response to changes in precipitation, and many bats in the family Phyllostomidae employ seasonal reproductive strategies. Because reproductive activities involve constraints on time and energy as well as increased nutritional demands, foraging behavior and home range size may differ between wet and dry seasons. Nonetheless, seasonal variation in response to landscape structure by bats has not been examined previously. Consequently, population-, ensemble- and assemblage-level responses of phyllostomids to landscape composition and configuration were quantified separately during the wet and dry season at three circular focal scales (1, 3 and 5 km radii) for 14 sites in fragmented lowland Amazon forest. Responses to landscape characteristics were scale-dependent, species-specific, and seasonal. Abundances of frugivores responded to landscape composition in the dry season and to landscape configuration in the wet season. Conversely, abundances of animalivores responded to landscape configuration in the dry season and to landscape composition in the wet season. Divergent responses to landscape structure between seasons suggest that variation in resource abundance and diversity play a significant role in structuring population-, ensemble- and assemblage-level patterns. As such, considerations of the effects of dietary flexibility and reproductive constraints on foraging strategies and habitat use may be important when designing management plans that successfully promote long-term persistence of biodiversity in fragmented landscapes.