Human population growth and the extinction of the tsetse fly

Abstract Agricultural expansion is a major cause of biodiversity loss worldwide. In Africa, biologists have observed that the populations of some tsetse species, which transmit human and livestock trypanosomosis, decline or disappear as human populations grow and farmers clear fly habitat for cultivation. The objectives of this paper are to synthesize the available information concerning human and tsetse populations and to develop a model to estimate the future effect of human populations on tsetse populations. A spatial, GIS model was developed to estimate future impacts using a combination of fine-resolution human population data for the years 1960, 1980, 2000, 2020, and 2040; field data on the relationships between human and tsetse population densities; and the distribution of different types of tsetse fly. By 2040, many of the 23 species of tsetse fly will begin to disappear and the area of land infested and number of people in contact with flies will also decline. However, none of the species of flies will be under threat of extinction by human agricultural activities in the near term. An area of Africa larger than Europe will remain infested by tsetse and under threat of trypanosomosis for the foreseeable future.

[1]  W. Ormerod.  Trypanosomiasis control and African rural development , 1986 .

[2]  Kenneth Hill,et al.  Demographic Change in Sub-Saharan Africa , 1993 .

[3]  R. Reid.  Impacts of trypanosomosis on land-use and the environment in Africa: State of our knowledge and future directions , 1999 .

[4]  W. H. R. Lumsden,et al.  The role of the trypanosomiases in African ecology , 1971 .

[5]  W. Wint,et al.  LIVESTOCK , LAND USE AND AGRICULTURAL INTENSIFICATION IN SUB-SAHARAN AFRICA , 1999 .

[6]  M. Upton.  Crop-livestock interaction in sub-Saharan Africa: J. McIntire, D. Bourzat and P. Pingali. The World Bank, Washington, DC, 1992. 246 pp. Price: $ 15.95 (Paperback). ISBN 0-8213-2166-8 , 1994 .

[7]  W. Ormerod.  A critical study of the policy of tsetse eradication , 1986 .

[8]  G. Hendrickx,et al.  The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo. , 1999, Veterinary parasitology.

[9]  R. Engst.  Who Technical Report Series: No: 567. Evaluation of Certain Food Additives, 19. Report of the Joint FAO/WHO Expert Committee on Food Additives, 23 Seiten. World Health Organization, Geneva 1975, Preis: SFr. 5,— , 1976 .

[10]  T. A. M. Nash,et al.  Tsetse flies in British West Africa. , 1948 .

[11]  C. A. Kofoid.  THE TSETSE FLIES OF EAST AFRICA , 1938 .

[12]  J. Okoth.  Further observations on the composition of glossina population at Lugala, South Busoga, Uganda. , 1982, East African medical journal.

[13]  Michael Taylor.  Diversity of life , 1994, Nature.

[14]  E. Wilson,et al.  The Loss of Diversity Causes and Consequences , 1988 .

[15]  P. Ellis,et al.  The social and economic implications of trypanosomiasis control. A study of its impact on livestock production and rural development in Northern Nigeria. , 1980 .

[16]  C. Laveissière,et al.  Ecologie des glossines en secteur pré-forestier de Côte d'Ivoire : 2. Les préférences trophiques de Glossina palpalis s.l. , 1982 .

[17]  A. Jordan.  The distribution of the fusca group of tsetse flies (Glossina) in Nigeria and West Cameroun. , 1963 .

[18]  K. M. Katondo.  Revision of Second Edition of Tsetse Distribution Maps , 1984 .

[19]  The Tsetse Flies of East Africa: , 1937, Nature.

[20]  W. Ormerod.  The relationship between economic development and ecological degradation: How degradation has occurred in West Africa and how its progress might be halted , 1978 .

[21]  W. F. Snow,et al.  The distribution of the tsetse flies Glossina morsitans submorsitans and G. palpalis gambiensis (Diptera: Glossinidae) in The Gambia and the application of survey results to tsetse and trypanosomiasis control , 1993 .

[22]  C. S. Holling,et al.  Biodiversity loss: Biodiversity in the functioning of ecosystems: an ecological synthesis , 1995 .

[23]  D. Bourn.  Tsetse control, agricultural expansion and environmental change in Nigeria , 1983 .

[24]  J. Ford,et al.  Maps of tsetse fly (Glossina) distribution in Africa, 1973 according to sub-generic groups on scale of 1:5,000,000. , 1977 .

[25]  W. Ormerod.  Africa with and without Tsetse , 1990 .

[26]  D. Wilcove,et al.  QUANTIFYING THREATS TO IMPERILED SPECIES IN THE UNITED STATES , 1998 .