Longitudinal differences in ¹⁵N between mothers and offspring during and after weaning in a small cooperative mammal, the meerkat (<i>Suricata suricatta</i>)

Gestation and subsequent lactation are energetically costly life history events for mammalian females. We used longitudinal delta15N data from hair samples from offspring and their mothers to explore lactation patterns in a small cooperative mammal, the meerkat (Suricata suricatta). Lactation enriched hair from meerkat offspring in 15N compared with that of their mothers, and this enrichment gradually declined after weaning. Although the observed peak enrichment of approximately 1 per thousand was substantially below the predicted levels of trophic enrichment in capital versus income breeders, we suggest that our results reflect an income breeding tactic in this species. Our study supports the notion that delta15N analyses can be a useful tool to investigate lactation schedules in mammals. However, reliable conclusions from 15N data regarding the nutritional tactics of mammalian females during reproduction may be limited by our scant understanding of the effects of various physiological variables on isotope assimilation.