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A hydrologic pond model was developed that simulates daily spatial and temporal variations (area, volume and height) of temporary ponds around Barkedji, a village located in the Ferlo Region in Senegal. The model was tested with rainfall input data from a meteorological station and from Tropical Rainfall Measuring Mission (TRMM) satellites. During calibration phase, we used climatic, hydrologic and topographic field data of Barkedji pond collected daily during the 2002 rainy season. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Digital Elevation Model (DEM) and a QuickBird satellite image acquired in August 2005 (2.5 m pixel size) were used to apply the hydrologic model to all ponds (98 ponds) of the study area. With input rainfall data from the meteorological station, simulated water heights values for years 2001 and 2002 were significantly correlated with observed water heights for Furdu, Mous 2 and Mous 3 ponds, respectively with 0.81, 0.67 and 0.88 Nash coefficients. With rainfall data from TRMM satellite as model input, correlations were lower, particularly for year 2001. For year 2002, the results were acceptable with 0.61, 0.65 and 0.57 Nash coefficients for Barkedji, Furdu and Mous 3 ponds, respectively. To assess the accuracy of our model for simulating water areas, we used a pond map derived from Quickbird imagery (August 2007). The validation showed that modelled water areas were significantly correlated with observed pond surfaces (r2=0.90). Overall, our results demonstrate the possibility of using a simple hydrologic model with remote sensing data (Quickbird, ASTER DEM, TRMM) to assess pond water heights and water areas of a homogeneous arid area.

A little modification was made on the classical Borel tube, used for rearing isolated females of mosquitoes. The first studies were realized with the main Yellow fever vector, Haemagogus janthinomys, in Brazil. The results are: a better survival, as far as 72 days, a greater number of eggs, up to 80, and a shorter trophogonic cycle of 7-8 days. So, one can imagine more easily further studies about the vertical transmission of the YF virus by this important neo-tropical mosquito.

The present communication describes a new species of mermithid nematode, Isomermis lairdi, found parasitizing blackflies in the Ivory Coast, West Africa. This nematode is the most common mermithid parasite of Simulium damnosum Theobald and occurs in the larval, pupal, and adult stages of this blackfly in streams of various sizes. The diagnostic characters of the adults of I. lairdi are (1) terminal mouth. (2) strongly S-shaped vagina, (3) ratio of spicule length to anal body width (1.7–2.8), and (4) circular amphids and amphidial openings.The postparasitic juveniles of I. lairdi differ from those of I. tansaniensis Rubtsov, 1972, in having three or four rows of cells in the lateral cords and a longer tail appendage in the male.This is the third species of mermithid nematode described from blackflies (including Simulium damnosum) in West Africa, and the first of the genus.

From material collected by R. Le Berre in 1972 and by J. J. Petersen and B. Mondet in 1975, two new species of Mermithidae are described from blackfly larvae, including Simulium damnosum s.l., for the first time in West Africa. These species, Gastromermis philipponi n.sp. and Gastromermis leberrei n.sp. possess a rudimentary excretory gland and the preparasitic larvae of the former contain a characteristic caudal appendage which is lost during penetration into the simuliid larvae. Therefore, these two species are the only ones of Gastromermis known to have six longitudinal cords.