Relationships of season, topography, habitat, and sex with the diet components of roe deer

Analyzing roe deer ( Capreolus capreolus ) diet in relation to season, topography, habitat, and sex is vital for understanding adaptive foraging strategies, predicting responses to climate change and habitat loss, and informing wildlife management through insights into population dynamics and food web interactions. This study, conducted across four seasons in 2023–2024 in northern Iran, examined a protected roe deer population via sampling of fresh fecal samples separated by sex. Dried and powdered samples were analyzed for 13 chemical components, including high-quality nutrients and digestibility-limiting components. The relationships between these components and season, elevation (topography), NDVI (habitat), and sex were then investigated. Key findings revealed significant seasonal variations: autumn showed lower fecal dry matter; summer had reduced fat and starch content; and spring was characterized by higher organic matter and lower ash levels. Additionally, males exhibited higher fat and fatty acid content compared to females, particularly in summer diets. Environmental variables including higher elevation and NDVI correlated with increased fecal fat and fatty acids. However, elevation, NDVI, sex, and season had no significant relationships with crude protein, nitrogen, or non-fiber carbohydrates. Regarding digestibility-limiting components, summer diets exhibited higher fiber concentrations (ADF, NDF, and NDFn) along with reduced hemicellulose content. Conservation implications emphasize protecting high-elevation, high-NDVI habitats to bolster roe deer fat reserves, especially for males with elevated needs. Management strategies should foster vegetative diversity to accommodate seasonal fluctuations in nutrient components, while integrating sex-specific dietary requirements to bolster population health and resilience against environmental stressors.