Mineral sources in natural habitats for a leaf-eating primate

Minerals are essential components of animal nutrition, playing a crucial role in health, reproduction, and survival. Studies show that mineral intake varies by species, habitat, and season. This study evaluates the mineral composition of food consumed by black howler monkeys (Alouatta pigra), an endangered primate in southeastern Mexico, considering differences among habitats (fragmented vs. conserved), strata (terrestrial vs. arboreal), seasons (rainy, dry, and Nortes), and food types. Leaves, fruits, and lianas (N = 84) were analyzed to estimate intake of key minerals (Ca, P, Mg, and K) in absolute (g/day) and proportional (% dry matter) terms. Results showed that foods from the forest fragment had higher concentrations of Ca (1.80 ± 1.06%) and Mg (0.37 ± 0.11%) and lower Na (0.01 ± 0.01) compared to the conserved forest (Ca: 0.76 ± 0.67%; Mg: 0.28 ± 0.1%; Na: 0.04 ± 0.01). Based on daily intake, Ca, P, and Mg were the most important. Seasonality influenced diet: during the Nortes season, Ca (2.20 g/day) and P (23.09 g/day) intake increased, linked to greater consumption of young leaves, with potential physiological implications due to their high concentrations. Mature leaves contributed over 50% of essential minerals like Ca, Mg, and Mn, while immature fruits were key sources of P and Cu. Ca intake in fragmented habitats was notably high, possibly with physiological implications. These findings underscore the role of dietary diversity in meeting mineral needs in fragmented environments. Despite mineral variation among foods, black howler monkeys attempted to meet requirements through varied food sources, reinforcing the importance of conserving plant diversity in fragmented ecosystems.