Mount Elgon's 'elephant caves'

Abstract

This illustrated article outlines geological and biological forces that are the basis of formation of the Mount Elgon caves as they are today. The rock is a volcanic agglomerate, a mass of small and large blocks of old solid lava ejected from an erupting volcano along with the new fine grained ash that bound it into solid rock. The caves 'have a central passage, semicircular in cross section and opening out into dome-like chambers floored with piles of collapsed rock slabs from the roof'. The caves, of which Kitum and Makingeny are the best known, have long been known to attract elephants and other animals. The herbivores enter the dark cave interiors to consume salts, mainly mirabalite and sodium sulphate (Glauber's salt) that effloresce from the cave walls. The crystals are gouged out by elephant trunks and bushbuck teeth and licked off wall by buffalo. 'Places where elephant have been most active in their subterranean geophagy are marked by substantial undercuts in the sides of the caves from the floor up to tusk reach.' Elephant are active throughout the caves wheras humans who use the salt to to feed their cattle use only the area where they can see under natural light conditions near the mouth of front of the caves. Streams have also been a responsible force in cave formation, as they flow down the mountain side and encountered bands of resistent rock waterfall were formed. Caves initially began as cavities behind such waterfalls, 'salts crystallize out from the damp, bare rock of the cavity, the elephants arrive, and the cavity is enlarged'. The authors note 'Mount Elgon's underground elephants represent a unique aspect of elephant behaviour that has been learned and passed down over countless generations'.