Savanna Zone Research Articles

Effect of Site-Specific Application of N and K Fertilizers on Cashew Growth and Yield in Ochaja, Kogi State, Nigeria

An experiment was conducted at the Ochaja Substation of the Cocoa Research Institute in Ibadan, Nigeria. Ochaja is located in the guina savanna zone of Nigeria. Plantation soil nutrient requirements were determined prior to applying the required fertilizers. The soil was deficient in nitrogen (N) and potassium (K), with values ​​of 0.41 g/kg soil and 0.012 cmol/kg soil, respectively, at depths 0–40 cm. This value was used to calculate cashew fertilization rates of 54 kg N/ha and 84 kg K2O/ha. Based on these values, four treatment combinations of two rates of nitrogen fertilizer and two rates of potassium fertilizer were formed and applied to young cashew trees on the field. Nitrogen fertilizer was applied at 0 and 54 kg N/ha while the Potassium was applied at 0 and 84 kg K/ha. Treatments were placed in a Randomized Complete Block Design (RCBD) with three replications, Cashew growth, nut yield and soil nutrient characteristics were measured. The first dose was applied in June while the second dose was applied in September of 2019 and 2020. Application of N fertilizer had a significant lowering effect on soil pH at both soil depths compared to the control and compared to N and K fertilizers applied together. Similarly, application of potassium-based fertilizer, with or without nitrogen fertilizer, slightly increased soil pH by 5.4%. Soil N had a significant effect (P < 0.05). Total N ranged from 0.5 g/kg to 0.7 g/kg soil for fertilizer treatments. N and K fertilizers did not significantly improve available soil phosphorus (P) across fertilization treatments. Exchangeable K in soil followed a similar trend with available P in different treatments. Yield of cashew nuts (280kg) improved significantly (P < 0.05) under application of sole nitrogen fertilizer and the control.

A comparative effect of legume-based cropping association on the productivity of Manihot esculenta Crantz in the forest and savanna zones of the Central African Republic

The objective of this study, conducted under integrated management in forest and savanna zones, is to improve cassava yields in rural areas of the Central African Republic using a comparative approach. The study design is a randomized block design with eight treatments (0 to 7) and four randomized replications, comprising 32 elementary plots. The different doses of PK or NPK fertilizers and/or those associated with legumes (0-0-0, legumes, legumes-30-180, legumes-90-30-180 and 90-30-180) were tested in the districts of Damara and Pissa. The trial was conducted over one agricultural season. The analyses were done using R software version 4.1.0 and Excel 2010. The results show that the doses of 90 kg.ha-1 of Nitrogen, 30 kg.ha-1 of Phosphorus and 180 kg.ha-1 of Potassium gave good productions in fresh roots at the scale of the two localities with average yields of 60 t. ha-1 (T3: cassava + groundnut + NPK) compared to 29 t.ha-1 (T0: cassava) in the forest zone and 37 t.ha-1 (T3: cassava + groundnut + NPK) compared to 23 t.ha-1 (T0: cassava) in the savanna zone. Economically, after the sale in pods, the cassava + legume treatments (T1: cassava + groundnut with a profit of 765,000 F CFA in the forest and 435,455 F CFA in the savanna and T4: cassava + cowpea with a profit of 78,725 F CFA in the forest and 265,000 F CFA in the savanna) are profitable for the farmer-producers in the study area. The use of the results of this study in rural areas of the Central African Republic can improve the production of fresh roots and pods. In any case, a study on spatial arrangements in cropping associations (strip cropping, intercropping) can be envisaged in order to better manage the soil and optimize production in rural areas.

Correlation coefficient of live weight and body measurements of extensively reared West African Dwarf goats in south west zone of Nigeria

The study was conducted in Ejigbo Local Government Area of Osun State, a derived savanna zone of Nigeria. Body measurements and live weight were assessed in 399 West African Dwarf (WAD) goats 194 bucks and 205 does. The data were segregated based on sex and age groups to obtain detailed information for characterisation goat in the experimental area. Body measurement values increased significantly (p ≤ 0.05) with age in both sexes. Mean body weight ranged from 5.32±0.15 kg to 29.63±1.88 kg in bucks, and 5.75±0.13 kg to 30.29±1.22 kg in does. Live weight was positively and significantly (p ≤ 0.05) related with most body parameters. Body length, heart girth, rump height had highest coefficient of correlation across ages. Phenotypic values were higher in male WAD goats than the female. Conclusively, body weight and linear body measurements are economically important traits in animal genetic resources especially small ruminants like goats. Selection for increase in any of the two phenotypic variables (live weight and linear measurements) will result in an equal increase in the other. Equally, live weights, in the absence of adequate records, can be utilized to predict traits that are correlated with linear measurements.

Can habitat characteristics of a West African forest‐savanna mosaic landscape model bee community composition?

AbstractBees are vital to both ecosystems and humans worldwide; supplying a range of key support facilities for the successful breeding of the majority of flowering plants. The aim of this study was to assess the bee species composition in a Sudano‐Guinean savanna zone and determining the impact of a set of environmental parameters influencing this species composition in four habitat types. Sampling was carried using yellow pan traps protocol. A total of 846 bees belonging to 3 families, 25 genera and 52 species were collected. The largest number of bee individuals was found in the Apidae family. The most abundant species was Hypotrigona sp. The highest bee species and number of individuals was recorded in the shrubby savanna. Bee species diversity and abundance were found closely correlated with the plant diversity. Gaining a better understanding of the factors influencing bee community dynamics in the given landscape can provide valuable information for conservation efforts, habitat management and help identifying species which ones could be domesticated.

Correction to: Effects of melatonin on interleukins and heat stress protein responses in donkeys subjected to packing during the hot‑dry season in the Northern Guinea Savanna zone of Nigeria

Correction to: Effects of melatonin on interleukins and heat stress protein responses in donkeys subjected to packing during the hot‑dry season in the Northern Guinea Savanna zone of Nigeria

Testing White’s Floristic Impoverishment Hypothesis in the Forest-Savanna Transition Zones of Africa

In tropical Africa, forests and savannas are the two most widespread biomes and potentially represent alternative stable states with a divergent species composition. A classic, but untested, hypothesis posited by White (1983) suggests that the transition zones between forests and savannas contain a floristically impoverished assemblage, with few representatives from each biome. Further, the evolutionary dimension of diversity has received limited attention, despite its importance for understanding the biogeographic history of biomes. Here, we quantified species richness and several measures of evolutionary diversity in 1° grid cells, using c. 300,000 occurrence records of trees and shrubs combined with biome affiliation data for 3203 species. We found that assemblages in transition zones hold fewer woody species than assemblages in forest and savanna zones, as posited by White. However, transition zones hold more phylogenetic diversity than expected given their species richness, whether one considers forest and savanna assemblages separately or together. We also show that the Congo Basin forest has low levels of phylogenetic diversity, given the number of species, and highlight south-eastern African savannas as a centre of savanna woody species richness and phylogenetic diversity. Regions with high phylogenetic diversity, given the number of both forest and savanna species, were centred around the Dahomey Gap and Cameroon, mainly in transition zones. Overall, our study shows that even if floristically impoverished, transition zones hold unexpectedly high evolutionary diversity. This suggests that they are important centres of evolutionary innovation and diversification and/or serve as evolutionary crossroads, where lineages that diversified in contrasting environments coexist within a single area.

Assessment of body linear measurements of semi-intensively managed Bunaji calves raised during major dry season in the derived savanna zone of Nigeria

Survival of semi-intensively managed cattle during dry season is critical towards their successful development. Cattle are of large size that obviously require high volume of feeds, for sustenance and productive purposes. A completely randomized design study over a period of three months during the major dry season (January to March) was carried out. The mean body measurements [chest girth (CG), body length (BL), body circumference (BC), tail length (TL), height at withers (HW) and body weights (BW)] were monitored fortnightly. The calves were allowed to graze in the morning, between 7.00 - 11.00 h and concentrate feed of 2 kg/day was offered in the afternoon on daily basis. Results from the study showed that the all the body measurements for the males increased till 6th week of the study, decreased till 9th week and thereafter increased till the 12th week. The estimated body weight for the males were 113.27 kg and 118.16 kg for the females at the end of the study. The mean CG was 122.89± 3.54 cm, BC was 132.41± 4.45 cm, TL was 81.74 ±2.01 cm, BL 89.54 ± 2.01 cm, HW 102.24 ± 3.22 cm and BW was 125.04 ± 2.89 kg. The correlation coefficient values were generally positive and significant. Highest positive correlations with significant differences were observed in all the parameters except for CG and BL (r= -0.07); and BL and HW (r= -0.57) which were negatively correlated. It was concluded that Bunaji calves would survive remarkably, with improved body measurements and weight gain if managed semi-intensively with available forage and concentrate during the dry season.

Effects of melatonin on interleukins and heat stress protein responses in donkeys subjected to packing during the hot-dry season in the Northern Guinea Savanna zone of Nigeria

Effects of melatonin on interleukins and heat stress protein responses in donkeys subjected to packing during the hot-dry season in the Northern Guinea Savanna zone of Nigeria

Serological detection of foot and mouth disease antibodies in apparenty healthy pigs within federal capital territory, Abuja

Swine production contributes significantly to the economic wealth of most farmers in developing nations including Nigeria. Foot-and-mouth disease (FMD) has been a highly contagious viral disease of agricultural importance in domestic ruminants and pigs, hampering livestock productivity in countries where the disease is still endemic. The study aimed to determine the swine FMD occurrence in order to elucidate the disease burden within Federal Capital Territory, Abuja and its environs. One hundred (100) sera were collected from Pigs and subjected to 3ABC ELISA test at the FMD Laboratory in National Veterinary Research Institute (NVRI), Vom. The result showed that out of 100 sera samples tested for FMD antibodies, 26 (26%) were positive and 74 (74%) were negative. Sero-positive distribution showed sow/gilt (32.7%), younger pigs (57.7%) and local breeds (50%) were more exposed to FMD. Although, this was not significant (P>0.05). Questionnaire report further showed knowledge attitude and practice (KAP) of farmers was good, however, the absence of vaccination could be a contributing factor to FMD spread to other susceptible and between carrier livestock within the study area. This finding suggests an increasing occurrence of FMD in pigs within the Guinea Savanna Zone of North-Central Nigeria. In conclusion, FMD antibodies were detected in apparently healthy, unvaccinated pigs of all breeds, ages and sex slaughtered and reared in the FCT. Control efforts should be put in place to prevent possible transmission of Foot and Mouth Disease between pigs and cattle and other ruminants within and between herds, market and slaughter slabs.

Effect of Soil and Climatic Conditions on Brown Spot Occurrence in Rice Lowland across Four Agro-climatic Zones of Côte d’Ivoire

Aims: To evaluate interaction of soil pH and acidity with weather on Rice Brown spot (BS) occurrence in rice lowlands.
 Study Design: Cross sectional study.
 Place and Duration of Study: Four distinct rice lowlands belonging to different climatic zones (forest, transitional and savanna) of Côte d’Ivoire during cropping seasons of 2021.
 Methodology: BS characterization were done in different farmer fields where soil samples were also collected during dry and rainy seasons. Soil silicon and acidity were determined in those samples and rice grain yield at harvest time were recorded in different sites. Weather data related to sites and seasons were used to find out correlations.
 Results: Occurrence of BS was found in forest zones with scores of 4 and 3 compared to 1 and 2 in savanna and transitional zones, respectively, with seasonal variation. Both rice production and the occurrence of BS were explained by soil parameters in conjunction with climatic parameters. Rainfall (R=0.38) and relative humidity (R=0.64) leaded BS occurrence and decrease of yield. Wind speed (R=0.62) and air maximum temperature (R= 0.63) were the determinant factors affecting rice yields. Si was found to be a component of sustainable soil management that interferes with soil pH in all climatic zones. Combined with Temperature, both soil parameters predicted BS occurrence over 50%.
 Conclusion: Temperature decrease BS pathogens occurrence whereas high humidity increases its spread. Those parameters combined with silicon which interferes with pH could leads sustainable solutions in BS control. Furthermore, having a deep understanding with rice varietal considerations can significantly improve strategies related to rice cultivation and protection.

Effect of Spacing on Growth and Grain Yield of Cowpea Varieties (Vigna Unguiculata) in Guinea Savanna Zone, Nigeria

Purpose: Field experiment was conducted at the Biotechnology Advanced Research Centre Farm, Garki-Abuja during 2022 cropping season to evaluate the effect of spacing on growth and grain yield of cowpea varieties. The experimental plot was ploughed and harrowed after which lining out was carried out. There were 24 plots with three replications. Each replicate consisted of 8 plots. Each treatment was in a plot size of 2.0 m x 2.0 m (4.0 m2). The alley way between replicates plots was 1.0 m and within replicates was 1.0 m. The treatments consisted of four spacing, (65 x 20 cm, 75 x 20 cm, 85 x 20 cm and 95 x 20 cm) designated as S1, S2, S3, and S4 and two cowpea varieties (TVU 14346 and TVU 14788). The treatments were 4 x 2 factorial experiment and fitted into a Randomized Complete Block Design (RCBD), replicated three times and data were collected on plant height per plant, number of leaves per plant, number of pods, pod length, number of seeds per plant, 100 seed weight, seed weight and grain seed yield. The seeds were sourced from the International Institute of Tropical Agriculture IITA) Ibadan. Two seeds were planted at the depth of 4 cm and later thinned to one three weeks after planting.
 Methodology: The treatments were subjected to analysis of variance (ANOVA) using CROP STAT statistical package and significant means compared using Duncan Multiple Range Test (DMRT).
 Findings: Results obtained revealed that the growth parameters of the plants increased as the plant aged with the highest number of leaves obtained from TVU 14788 (40.20) variety. There was significant (p≤0.05) difference in the yield performance with the highest grain yield gotten from TVU 14788 (7.42 t/ha) and the plants spaced with S1 (8.79 t/ha) gave the highest mean grain yield while the least mean value was received from S4 (3.98 t/ha).
 Unique Contribution to Theory, Practice and Policy: From this study, it could be stated that for optimum yield performance TVU 14788 and S1 thrived better than other treatments evaluated and could be recommended for farmers within this ecological zone.

English

The production and adoption of sorghum-improved varieties are faced with biotic and abiotic stresses affecting both its utilization and marketability by different actors in the sorghum value chain. This study aims to understand why and how different social groups and value chain actors make decisions on the utilization of sorghum and how these decisions influence the choice and adoption of the sorghum cultivars introduced and promoted by the breeding programs. This study was conducted in Mali’s Sudan and Savanna zones, wherein the different agroecological zones have differentiated production and utilization realities and traits demand. Mixed methods (surveys, focus group discussions, key informant interviews) combined with intersectional and value chain approaches were used for data collection and analysis. The data were collected from 836 respondents in 12 villages including 384 females (46%) and 452 males (54%) representing sorghum growers, processors, consumers, and traders. While the findings show gender-specific trait preferences, actors’ traits choices revealed the gender dynamics in value chains in which the different roles, interests, and challenges of men and women influence their choices and adoption of sorghum cultivars. The results also revealed there is an increased opportunity for the sale of sorghum grains (38%); this may be explained by the continuous efforts made by research institutes to develop high-yield sorghum varieties and the evolving processing sector in Mali.   Key words: Sorghum, gender, traits preferences, breeding, Mali.

Extreme Copper Isotope Fractionation Driven by Redox Oscillation During Gleysols Weathering in Mun River Basin, Northeast Thailand

AbstractCopper (Cu) isotopes are utilized to track Cu geochemical cycling in weathered gleysols of tropical zones. A significant isotope fractionation of Cu in these soils is primarily redox‐controlled; however, it is rarely reported how the frequency of redox fluctuations affects the soil Cu isotope signature. This study investigated the variations of Cu content and isotope fractionation in two low‐humic gleysol profiles (S1 and S2) from a dry tropical savanna zone. Owing to redox oscillation during weathering, δ65Cu values in profile S2 showed a stronger positive correlation with the mafic index of alteration of reducing environment than S1, and isotopically light Cu is more retained in the Zone II of profile S2 than S1. As the frequency of redox fluctuation increased, the retained stable Cu(I) species and light Cu isotopes increased in the residual soils through re‐adsorption or re‐precipitation by iron oxyhydroxide (i.e., ferrihydrite). Importantly, an Mn‐enriched zone was formed after reduction events in profile S2, and found to be enriched in light Cu isotopes. The heavier Cu fraction might be lost by adsorption on Fe oxyhydroxides in the Mn‐rich zone, while the relatively light Cu might be retained through adsorption on Mn oxyhydroxides. Additionally, a significant Soil Organic Carbon (SOC) contribution to Cu was found due to the high δ65Cu‐SOC correlation (R2 = 0.80) in S1 (depth <1 m). Therefore, our study shows that the Cu isotope signature can respond to redox changes in the terrestrial ecosystem, and these Cu isotope signatures may have significant implications for assessing soil ecological vulnerability under future climate change scenarios.

Influence of land use types on the distribution of selected soil properties in tropical soils of the Coastal Savanna zone

Globally, efforts are being made to identify land use types that could potentially improve carbon sequestration to mitigate climate change and global warming and ensure sustainable agriculture. The study was conducted at the University of Cape Coast Teaching and Research Farm to evaluate the influence of different land use types on the distribution of SOC at different soil depths. A stratified random sampling technique was used to collect a total of 180 soil samples at 0–15 cm, 15–30 cm and 30–45 cm depths from arable, fallow, pasture and plantation fields, covering about 24.52 ha. The physico-chemical properties of the soil samples were determined using standard laboratory methods and the data generated was analysed using Minitab 19. The results showed that land use systems significantly (p ≤ 0.05) affected the distribution of the physico-chemical properties of the soil. The SOC content under the different land use types was in the order; of plantation (2.57%) > arable (1.99%) > pasture (1.55%) > fallow (1.14%). The plantation field significantly (p ≤ 0.05) had higher SOC compared to the other land use types and that could be adopted as a better carbon store that can help in mitigating climate change. The mean values of SOC content and most of the other physico-chemical properties determined were generally concentrated in the topsoil (0–15 cm depth) but decreased with depth, so managing these fields properly can equally improve the availability of these nutrients towards sustainable agriculture.

The impact of climate change on the productivity of cowpea (<em>Vigna unguiculata</em>) under three different socio-economic pathways

Crop models are useful tools for simulating the impact of climate change on crop growth, development and yield. This study assesses the impact of climate change on cowpea yield in soils with low levels of phosphorous content mainly in the Sudan Savanna and Forest Transition Zone of West Africa. A crop model solution within the general modelling framework SIMPLACE in combination with the output of four climate models for 3 contrasting shared socio-economic scenarios (SSP126, SSP370, and SSP585) was used to simulate the impact of climatic change on phenology, above ground biomass and yield parameters of cowpea. The simulations were carried out for Ouagadougou and Kumasi, representing the two major savanna biomes in West Africa (Sudan Savanna and Guinea Savanna). Previous field experimental data on the wide-spread cowpea genotype Asontem from a P-deficient soil at Kumasi (Ghana) were used to validate the SIMPLACE crop model solution. The model was able to simulate the impact of irrigation and fertilizer management on cowpea growth and yield assessment with adequate accuracy. Compared to historic simulations of the biomass and yield of cowpea, the model solution projected higher above ground biomass, and yield under the pre-dominant low input cropping systems for all the three SSPs as a result of the rise in CO2 and in spite of slightly shorted growing cycle length in both locations.

Incidence of snakebites in rural communities living in the Paoua savannah and Mbaïki forest areas in Central African Republic

Snakebite is one of the most deadly neglected tropical diseases in Africa with more than 20,000 deaths reported each year. According to recent data from hospital in Central African Republic studies, the Paoua health district reports between 300 and 400 cases of ophidian envenomation each year. However, no epidemiological study on snakebites has been conducted at national level, nor a control strategy developed. The objective of this study is to describe the epidemiological aspects of snakebites in two rural communities, one located in savannah zone and the other in forest zone (both secondary and primary forest) in order to ensure adequate management of snakebites in these regions. Prospective community-based study in two health districts in the Central African Republic, the health district of Paoua in savannah area and the health district of Mbaïki in forest area, from December 2019 to January 2021. Snakebites were investigated in the community by selected trained people in charge of reporting data regarding all known cases of snakebites occurring during the study period. The data were actively notified either by health personal or community health workers in order to determine the circumstances and severity of the bite, its management and the clinical course in case of envenomation. A total of 412 snakebite cases were recorded during the study period, of which 198 cases occurred in the rural community of the forest zone and 214 in the community of the savannah zone. Case fatality rate was 5% in the forest zone and 1% in the savanna zone. The incidence rate of snakebite was significantly higher in savannah children compared to those in the forest (98/100,000 vs. 25.1/100,000; p<0.00001) while this incidence rate was significantly lower from age 45 onwards in the savannah area compared to the forest area (167/100,000 vs. 200/100,000; p=0.02). The case fatality rate of children and adults up to 44 years of age appeared to be significantly higher in the forest zone (7 deaths vs 1 death). Snakebites occurred significantly more frequently during field activities in the savannah zone than in the forest zone (51% vs 26%; p<0.0001). The symptomatology of bites was dominated by edema of the bitten limb and bleeding in the two study areas, compatible with cytotoxic and hemorrhagic syndromes due to viper bites. With an incidence rate of more than 160 cases per 100,000 inhabitants in the active population aged 15-44 years in rural communities of the forest and savannah zone, snakebites remain a public health problem in Central African Republic. A study on the toxicity of snakebites in Central African Republic is recommended. Besides, it is urgent to make anti-venomous serums available in health facilities in order to reduce the mortality related to the envenomation.

Use of biochar for enhance carbon sequestration to mitigate climate change and growth of maize in Sudan savanna zone of Nigeria

Application of biochar to the soil improves its physical, chemical and biological characteristics, promoting plant growth and productivity. The potential of biochar for carbon sequestration and its ability to reduce greenhouse gas emissions make it a very interesting alternative to counteract the adverse effect of climate change. The study examined the use of Biochar to enhance carbon sequestration and growth of maize in theSudan savanna zone of Nigeria. The experiment was conducted during the dry season of 2021/2022 at the Teaching and Research Farm of the Federal College of Horticulture, Dadin Kowa, Nigeria. Treatments involved seven levels of biochar (0, 2.5, 5.0, 10, 20, 30 and 40 t ha-1) which laid out in a randomized complete block design replicated three times. Data were collected on growth parameters, yield and yield components and post-harvest soil parameters were also determined for each treatment. Results indicated that biochar improves soil properties such as soil organic carbon, total nitrogen, available phosphorus and water-holding capacity of the soil. Carbon was sequestrated with biochar application and significantly higher under 40 t ha-1 treatment. It is recommended that biochar could be used for improved soil properties and carbon storage to mitigate the greenhouse effect.

Awareness and adoption of drought tolerant Maize in Guinea Savanna and Forest-Savanna Transition zone in Ghana

Awareness and adoption of drought tolerant Maize in Guinea Savanna and Forest-Savanna Transition zone in Ghana

Maize yield as affected by the interaction of fertilizer nitrogen and phosphorus in the Guinea savanna of Nigeria

The soils of the Nigeria savannas are particularly low in nitrogen (N) and phosphorus (P) and negatively affects maize productivity. The main objective of the study was to evaluate the interactive effect of N and P fertilizers on maize growth, grain yield, nitrogen uptake and N use efficiency. Field experiments were conducted during the 2015 and 2016 cropping seasons at Iburu in southern Guinea and Zaria in northern Guinea savanna zones of Nigeria. The treatments consisted of three levels of nitrogen (0, 60, and 120 kg N ha−1) and three levels of phosphorus (0, 13, and 26 kg P ha−1). The experimental design consisted of three replications in a split-plot design, with N as the main plot and P as the subplot. Our results show that the response of maize to N depends on the application of P. Higher yields were obtained with the combined application of 120 kg N ha−1 and 26 kg P ha−1 in both locations. With no P applied, plant N uptake (PNU) was greater at N rate of 120 kg ha−1 at Iburu while in Zaria, it increases with increase in N from 0 to 60 kg ha−1. When P was applied at 13 kg ha−1, the PNU increased by 52 and 66% at Iburu while in Zaria the increases were 51 and 57% each with N application of 60 and 120 kg ha−1, respectively, compared with zero N rate. The values for N recovery efficiency (NRE) and agronomic efficiency (AE) were lower for N rate of 120 than for 60 kg ha−1 irrespective of P application rate at both locations. The N utilization efficiency (NUTE) however was higher at 120 N kg ha−1 under 26 kg P ha−1across locations. It can be concluded from these results that in low fertile soils environments such as the Nigeria savannas, N fertilizer should be applied along with P fertilizer for optimum growth, grain yield and nitrogen use efficiency of maize.

A cross-sectional study of Simulium damnosum sensu lato breeding sites and species distribution in Sudan savanna, mixed savanna–forest and rainforest regions in Cameroon

BackgroundThe presence of breeding sites and distribution of species of Simulium damnosum sensu lato are critical in understanding the epidemiology of onchocerciasis and evaluating the impact of elimination interventions. Reports on breeding sites and species distribution of members of S. damnosum s.l. in Cameroon are scarce and the few ones available date back to more than three decades. The aim of this study is to provide information on S. damnosum breeding sites across the rainy (RS) and dry (DS) seasons and the species composition in three different regions in Cameroon: Southwest (SW), Northwest (NW) and North (N).MethodsA cross-sectional two-season study was carried out in three regions with different ecological characteristics (SW—rainforest; NW—mixed forest–Guinea savanna; N—Sudan savanna). Pre-control onchocerciasis endemicity, relief maps and historical entomological information were used to identify potential rivers for purposive sampling. Sampled larvae were fixed in Carnoy’s solution and sorted, and S. damnosum s.l. larvae were stored until identification by cytotaxonomy. Geographical coordinates of potential breeding sites were recorded to produce maps using ArcGIS, while Chi-square tests in SPSS were used to test for any differences between black fly seasonal breeding rates.ResultsA total of 237 potential breeding sites were sampled (RS = 81; DS = 156) and 72 were found positive for S. damnosum s.l. The SW had the most positive sites [67 (RS = 24; DS = 43)], with a significant difference in the rate of breeding between the seasons (P < 0.05). Among 68 sites visited in both seasons, 16 (23.5%) were positive in one of the two seasons with more sites positive in DS(11) than RS(05), 14 (20.6%) and 38 (55.9%) respectively positive and negative in both seasons. Simulium damnosum sensu stricto and S. sirbanum were the main species in the N, while S. squamosum and S. mengense were the predominant species in the NW and SW. Simulium soubrense and S. yahense were uniquely recorded in the SW.ConclusionsA comprehensive mapping of breeding sites requires rainy and dry seasons sampling. This study demonstrates that a breeding site survey of S. damnosum s.l. is achievable in forest as well as savanna zones. Not all potential breeding sites are actual breeding sites. Observation of S. soubrense in the SW indicates changes in species composition over time and could affect onchocerciasis epidemiology in this area.Graphical abstract