Towards a Space-Time Information System for the Description of the Population Dynamics of Glossina brevipalpis and Glossina austeni in the Kwa-Zulu Natal Province of South Africa
|Project type:||Consulting Series RTD|
|Geographic keyword: Africa | Republic of South Africa|
|General keyword: Remote sensing | Disease modeling|
|Specific keyword: Stepwise multivariate regression analysis | Geostatistics | Tsetse | Glossina austeni | Glossina brevipalpis|
Tsetse presence-absence prediction model for Glossina austeni and Glossina brevipalpis in KwaZulu Natal - South Africa
Following a major outbreak of Nagana in 1990 in KwaZulu Natal (Kappmeier et al., 1998) the OVI entomological team has conducted a series of field surveys from 1992 till 1999 to map the presence of Glossina austeni and G. brevipalpis, the two tsetse species remaining after the successful eradication of G. pallidipes in the late 1940ï¿½s.
The traps used during these surveys were mostly sticky panels such as used to capture G. austeni in Zanzibar (Vreysen et al., 1996) and improved (color, shape, odor-bait) by Kappmeier (unpublished, 1996). At a later stage a new odor-baited trap, the H-trap, was developed (Kappmeier, 2000) which significantly increases catches. It nevertheless was decided for comparative purposes to further use the improved sticky panel traps throughout the survey.
As part of a study to investigate the feasibility of eradicating both tsetse species from KwaZulu Natal, Avia-GIS was requested to develop a satellite derived presence/absence model for both species to enhance the obtained field survey results, highlight potential habitats and assist in the planning of proper vector suppression strategies.
Two key outputs of this consultancy are made available here: (a) the project report and (b) a paper presented at the ICPTV meeting "Tsetse and Trypanosomiasis Research and Control in Southern Africa: Past Present and Future", held in Pretoria (Republic of South Africa).
The report is divided in two parts:
PART 1 includes a discussion of obtained model outputs with particular reference to the results obtained during the field validation exercise and the contributions made by Drs Nevill and Kappmeier at OVI.
PART 2 describes in detail the material and methods used to develop the models, further avenues for research and different sampling scenarios based on obtained results.
The following products were also delivered to Mr. Roy Williams, GIS specialist at OVI:
A CD set (10 Gb) of the raw and processed NOAA-AVHRR1 satellite data used in this study. Data include all available material for 1997, 1998 and 1999.
Avia-GIS NOAA Tools V1.0 software allowing the download and processing of NOAAAVHRR data to further conduct similar studies2.
A GIS project including (a) all relevant data layers to enable further analysis and updates, (b) a set of geo-referenced pictures of relevant landscapes and habitats gathered during the validation fieldtrip and (c) a PowerPoint presentation of obtained results.
In the paper the obtained model outputs are summarised and suggestions are made for some avenues for future research. During the oral presentation at the workshop results of a field validation exercise were also discussed but are not included in the paper.
Legend to the figures: