Title: Roe is not red: Contrasting factors affecting forest-island use by two cervid species in a human-dominated landscape

Small forest patches may play an important ecological role in fragmented agricultural–forest landscapes, yet their importance for large herbivores remains poorly understood. We investigated factors affecting the use of forest islands (0.1–20 ha) by roe deer ( Capreolus capreolus ) and red deer ( Cervus elaphus ) in northeastern Poland. Using pellet group counts conducted on 150 forest islands and in compact forest complexes, we analysed the effects of internal habitat characteristics and surrounding landscape structure at local (300 m) and landscape (1000 m) spatial scales with generalized linear mixed models. Roe deer relative use of forest islands increased with cover conditions and the dominance of alder and spruce stands, whereas red deer use was positively associated with island area and tree cover. Human settlements reduced forest island use by both species at the local scale, although red deer were additionally negatively affected by isolated buildings. Roe deer used forest islands less frequently near compact forest complexes, while neighboring forest islands reduced use by red deer. Among surrounding crops, only oilseed rape positively affected forest island use, and only in roe deer. Red deer showed higher relative use of compact forest complexes than of forest islands, whereas roe deer showed similar relative use of both habitat types. Our results demonstrate species-specific responses to forest fragmentation driven by differences in habitat requirements and spatial ecology. Forest islands may represent locally important areas of space use for both deer species within fragmented landscapes. Incorporating small forest patches into spatially explicit forest and wildlife management may improve the understanding of deer space use in fragmented landscapes and contribute to reducing potential human–wildlife conflicts.