Multiproxy studies on dung of endangered Sangai (Rucervus eldii eldii) and Hog deer (Axis porcinus) from Manipur, India: Implications for paleoherbivory and paleoecology

Abstract

Pollen and non-pollen palynomorph analyses of 16 summer and winter dung samples of two endangered deer species, Sangai (Rucervus eldii eldii M'clelland) and Hog deer (Axis porcinus Zimmermann) from Keibul Lamjao National Park of Manipur, northeast India, was undertaken to examine the dietary preferences of these species in relation to the vegetation and ecology of the region. Grass is the primary food for both the deer species, which though obvious based on direct observation, is also supported by our dataset, as indicated by the abundance of grass pollen and phytoliths in the dung assemblage. Additionally, marshy and aquatic taxa are present and indicative of the importance of these plants in the diet of both species and indicate the utilization of the perennial water-logged habitat present in the region. The relative abundance and diversity of arboreal taxa in the summer dung samples is consistent with the extant vegetation. Fungal spores, especially coprophilous fungi, were consistently present in the assemblage, although in low values. Energy Dispersive Spectroscopic (EDS) analysis on the dung samples indicates that silica content was higher in the winter season compared to the summer dung samples. Multivariate principal component analysis (PCA) was applied to the quantified data obtained from pollen and phytolith frequency analyses of the dung samples and clearly revealed a significant variation in vegetation types based on pollen and phytoliths. These generated data will be helpful to document and understand seasonal difference in dietary preferences and ecology of the two deer species along with the other associated herbivores in the region. The palynodata is also useful in tracing the relationship between modern pollen and vegetation, which is challenging to accomplish systematically due to seasonal flooding of the region.