La léthargie chez les Chiroptères cavernicoles d'Afrique Centrale

Abstract

Lethargy in thé cavernicolous Chiroptera in Central Africa From his personal research undertaken in thé subterranean field (natural and artificial cavities) in Shaba (ex-Katanga, in S.E. Zaïre) and Rwanda, thé author briefly defines thé macroclimate of thé prospected régions as wel] as thé microclimate of thé subterranean habitat (humidity and température). A réversible hypothermia has been noticed in thé dry season only (from May till August) in eleven species of troglophile Chiroptera belonging to thé following families: Rhinolophidae (7 species of Rhinolophus), Hipposideridae (only Hipposideros ruber) and Vespertilionidae (Miniopterus inflatus rufus, Miniopterus schreibersi arenarius & M.s. natalensis, Myotis tricolor). No sign of lethargy has been noticed in thé Megachiroptera (Lissonycteris angolensls, Rousettus aegyptiacus leachi), Emballonuridae (Taphozous perforants sudani), Hipposideridae (Cloeolis percivali australis) or Nycteridae (3 species of Nycteris). There could be corrélations between lethargy and breeding if one takes into account thé phenomena of late ovulation and delayed implantation. The entry into lethargy is not caused by thé scarcity of food. It does not concern ail thé individuals of a colony or in various populations of a cave. The degree of humidity appears to be more important than thé température as far as thé conditions for hibernation are concerned.