ECOLOGICAL PATTERNS OF ANTHROPOGENIC MORTALITY OF SUBURBAN SNAKES IN AN AFRICAN TROPICAL REGION

Abstract

The ecological patterns of anthropogenic mortality of snakes in the Niger Delta (southeastern Nigeria), as well as factors that attract or force snakes into human settlements, are investigated in this paper. The snake species richness in suburban environments of the Niger Delta is remarkable, and includes about 36% of the species presently known from the area as a whole. The proportion of dangerous species is low. Anthropogenic mortality rates stood at a conservative mean estimate of 0.110 snakes/effort hour, while the mortality frequency peak occurred in the rainy month of June (0.559 snakes/effort hour). This mortality peak coincided with the onset of the inundation period of the swamps. The flooding of their forest habitat, and the presence of abundant food supply and shelters seem to be the main factors favoring the establishment of snake populations in urban environments. About 50% of snakes were killed intentionally by people, but vehicles and trapping with snares (set for mammals) were also importa...