Breeding Site Characteristics of Mosquito in Ouagadougou, Burkina Faso

Urban areas deal with the emergence or resurgence of transmissible and non-transmissible diseases, linked in particular to urban lifestyle and sanitation issues. Human practices create or maintain conditions that favour mosquitoes’ breeding. This study investigates mosquito breeding sites characteristics in Ouagadougou, from September to November 2020. Mosquito larvae were sampled across three districts in the city, chosen based on socio-demographic and urbanization levels. The larval collection from natural breeding sites using the ladle technique and larvae transferred to can. For artificial sites, the larvae were transferred directly into can Larvae were collected from 83 breeding sites, predominantly artificial: 39% in plastic containers, 23% in clay containers, and 13% in metal, while natural sites like puddles accounted for only 25%. A total of 8352 mosquitoes were identified as six species: Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, Anopheles gambiae s.l., Anopheles funestus, and Mansonia africana. Ae. aegypti was the most prevalent, found across all breeding site types, whereas Culex quinquefasciatus and Anopheles gambiae were mainly in natural sites. Physico-chemical analysis of the breeding sites revealed that conductivity and turbidity were consistent across breeding sites. The highest median pH values were observed in ceramic and metal containers. Water temperature showed minimal variation. The presence of Anopheles gambiae and Culex quinquefasciatus correlated with higher water temperature, turbidity, and conductivity. Anopheles funestus preferred high pH environments. Conversely, Aedes aegypti, Aedes albopictus, and Mansonia africana were less influenced by these parameters. The findings underscore the need for community involvement in water and waste management to control mosquito populations, especially targeting the Aedes aegypti species. Raising awareness among locals about proper water storage and disposal practices is crucial for effective vector control.

Modeling Bat Species Richness and Spatial Distribution in Burkina Faso

The spatial distribution of bats in Burkina Faso is little-known. Previous studies have only described the bat species’ richness in Burkina Faso. This study was conducted to highlight bat species’ richness distribution within Burkina Faso and environmental variables that influence this distribution with the aim to give support for protection and further sampling for biodiversity. The Species Distribution Models (SDMs) were used to perform this study. To do that, species occurrences were collected throughout literature and field sampling and correlated to environmental variables through the Maxent software (Maximum Entropy). Our modeling variables included climate, vegetation cover, topography and hydrography data. The Jackknife test was performed to determine the importance of environmental variables that influence the species distribution model. The results showed that bats are present in all areas of vegetation in Burkina Faso. Species richness varies across the country. The species richness for major families increases from North to South. The total annual precipitation and topography are the main variables that positively influence bats distribution in Burkina Faso but the bare ground cover and standard deviation of the maximum temperature negatively influence this distribution. This modeling approach of bat species richness is important for policies makers and represents an invaluable tool in ecological management, particularly in the current context of climate change.

Fishermen Local Knowledge and Aquatic Environmental Change: Impacts on Fishing and Adaptation Strategies in Volta Basin

Climate researches predict that climate change will have an important impact on aquatic and terrestrial ecosystems. However, many fishermen do not have a lot of knowledge about climate change or how it might affect their fish catch yields and overall fishing operations in the future. The objective of this study was to assess local fishermen’s perception of global change on the ichthyofauna of the Volta Basin in Burkina Faso. Focus group interviews were conducted between March 2019 and July 2020 in 19 reservoirs of the Volta Basin. A total of 242 fishermen divided into 34 groups participated in the interviews. The results showed that fishermen are aware of climatic and anthropogenic threats to fish fauna. According to them, these global changes lead to important modifications in the structure of the ichthyofauna ranging from seasonal mortality of fish (Mormyridae) to the extinction of certain species such as those of the genera Lates, Hydrocynus and Heterotis. These changes also lead to a loss of fish habitat through silting and lower water levels in the reservoirs. Statistical analysis of the collected data showed that the main factors threatening the structure and dynamics of fish are mainly agriculture and market gardening around the dam lakes, the temperature increase and the trend of decreasing rainfall. Thus, the main pressures responsible for the mortality and/or extinction of fish are market gardening pollution (100%), bad fishing practices (63.15%) and high temperatures (47.5%). As for adaptation measures and management strategies, the most important were training and sensitization of stakeholders (78.94% of citations) followed by fish stocking (21.05%). This endogenous knowledge is important for the development of climate change adaptation programs.