Kenyan Elephant Feed Preferences Explored by near Infrared Spectroscopy

Abstract

Near infrared (NIR) spectroscopy was used to examine leaf and bark samples from Mount Kenya Forest Reserve to investigate the feeding preferences of elephants. Systematic differences were observed in specific spectral regions between leaf material from preferred ( Lasianthus kilimandscharica) and non-preferred ( Bersama abyssinica) tree species, i.e. 1640–1750, 2000–2150, 2200–2250 and 2280–2400 nm. Differences between bark samples from preferred ( Eucalyptus saligna) and non-preferred ( Vitex keniensis) tree species were observed in the 1100–1200, 1300, 1640–1750 and 2250–2400 nm regions. Qualitative multivariate analysis of the spectral data using principal component and cluster analysis achieved complete separation of the preferred and non-preferred samples for both leaf and bark material. Interpretation of the spectral data was used as an aid to select which chemical analyses should be performed next. In addition to phenolic compounds, it is suggested that nitrogenous, carbohydrate and fibre fractions be examined.