Tracing the Source of the Elephant And Hippopotamus Ivory from ...

Chapter 7
Ecological and Dietary Requirements of Hippopotami
Additional lines of evidence for the geographical distribution of the hippopotamus
in the Late Bronze Age may be found by examining the ecological and dietary
requirements of the animal. As shown in Chapter Six, these factors also prove
indispensable for interpreting the carbon, oxygen, and nitrogen stable isotope ratio
analyses. In all there are two genera of hippopotami: Hexaprotodon and Hippopotamus.
Only one modern species is recognized in either genus, and these are the West African
pygmy hippopotamus (Hexaprotodon liberiensis) and the more commonly known
Hippopotamus amphibius (Eltringham 1993: 41).
First, unlike the pygmy hippopotamus, Hippopotamus amphibius cannot live in
forest or thick brush. The hippo instead resides in all types of water: rivers, lakes, muddy
wallows, and even off the sea shore. The skin of the hippopotamus is very sensitive and
cracks if exposed to direct sunlight for too long. The animal therefore requires a source
of permanent moisture, whether it be water or its much-loved wallowing medium of mud
(Eltringham 1999: 4). Hippos may leave the water source during the day but will return
if they become overheated. The body of water hippos inhabit must also be suitably vast
to accommodate the male hippos in their territorial requirements. Indeed, the male
hippos are only territorial in water and each lords over a strip of shoreline and associated
bank. Klingel (1991) documented the sizes of these linear territories in Uganda as
varying from 250-500 m on the lake shore, although in rivers they were considerably
shorter (50 to 100 m in length) Females, on the other hand, are not territorial and
furthermore not tied to any one male territory. After grazing most females return to the
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