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The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama (Hemiptera: Liviidae) is a destructive, invasive species that poses a serious threat to the citrus industry wherever it occurs. The psyllid vectors the phloem-limited bacteria 'Candidatus Liberibacter americanus' and 'Ca. L. asiaticus', causal agents of the incurable citrus greening disease or huanglongbing (HLB). It is essential to understand which regions and areas are suitable for colonization by ACP to formulate appropriate policy and preventive measures. Considering its biology and ecology, we used a machine learning algorithm based on the MaxEnt (Maximum Entropy) principle, to predict the potential global distribution of ACP using bioclimatic variables and elevation.The model predictions are consistent with the known distribution of ACP and also highlight the potential occurrence outside its current ecological range, that is, primarily in Africa, Asia and the Americas. The most important abiotic variables driving the global distribution of ACP were annual mean temperature, seasonality of temperature and annual precipitation.Our findings highlight the need for international collaboration in slowing the spread of invasive pests like D. citri. © 2022 Society of Chemical Industry.

The introduction of fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae) into Ghana is a threat to maize production. This study determined the severity of this pest on maize production subjected to Bacillus thuringiensis (Bt), emamectin benzoate (Eb) sprayed and unsprayed farms under farmers’ practices in Ghana. At least one farm per treatment was selected in each Agro-Ecological Zone (AEZ) for data collection throughout the maize phenology during three production seasons. Percent damaged plants and ears were determined, the proportion of feeding damage on leaves and ears was scored, and yields measured on each farm. Ear damage was most severe in the Guinea Savannah Agroecological Zone with a correspondingly lower yield. The highest yield was recorded from the Tropical Rain Forest zone. The damage levels decreased when plants aged, but the scoring of damage level on attacked ears was greater than that on leaves. Maize plant damage was highest with corresponding lowest yields on unsprayed farms compared to sprayed farms which recorded similar results for both insecticides. Bt and Eb based insecticides (applied at 50g/15L H2O/ha and 75mL H2O/ha, respectively) are effective on FAW larvae and are therefore recommended for FAW management in Ghana.

One of the most important bioindicators of change in habitat conditions, especially in tropical Africa, is change in insect diversity. In line with that, the dynamics of Orthoptera and Hymenoptera insect orders were studied and used as evidence of change in ecosystem health after a similar study on Lepidopteran groups revealed some level of degradation in the Tarkwa Gold Mine (TGM). Orthopteran and Hymenopteran species assemblages were sampled within the mine and characterised based on family diversity. Transect counts, sweep netting, malaise trapping and flight interception trapping methods were employed to sample abundance and diversity of insect assemblages of the above-mentioned insect orders. Results showed that few species belonging to these two orders were recorded within the mine, although the records were dominated by more aggressive and habitat degradation tolerant members as reported for the Lepidopteran group in a previous study. We conclude that records of diversity of these insect orders in this study shows a reduction in the ecosystem health within TGM. This finding is further proof that there is a general decline in biodiversity within the concession and hence care must be taken to encourage environmentally-friendly mining practices to avoid further degradation. Recommendations are made for environmental management to maintain more natural vegetation to serve as refugia for impacted animals within the concession.

Diversity of insect communities can be used as bioindicators for change in the environment especially in farms under different management systems. In line with that, we conducted a research on insect species associated with cocoa under organic and conventional management systems in the Eastern and Central regions of Ghana. Insect collection was done using Hand height visual count, Canopy, and “Knock down”, pitfall, coloured bowl and fruit-baited traps. A total of 13,742 individual insects belonging to 138 species from 63 families and 12 orders were recorded in the study. Insect abundance and diversity were generally higher in organic farms compared to conventional farms with Oecophylla longinoda as the most dominant species in both management systems and especially more dominant in organic cocoa farms. Our study revealed that most of the insect species recorded were known cocoa pests although there was high abundance of beneficial insects too. Some of the pest species were Planococoides njalensis, Salhbergella singularis, Helopeltis spp and Pseudococus spp, while some of the beneficial insects recorded were Pheidole spp, Tegenaria spp, Camponotus spp, Crematogaster spp. We can conclude that cocoa farms are potential habitats for insect biodiversity conservation. We recommend that management and/or agronomic practices used in cocoa farms should be geared towards protecting beneficial organisms for instance pollinators and natural enemies by effectively suppressing insect pest populations while enhancing good seed production.

Mensah BA, Kyerematen R, Annang T. 2018. Influence of human activity on diversity and abundance of insects in three wetland environments in Ghana. Bonorowo Wetlands 2: 33-41. The Wetland environment is unique with unique biota that includes insects. Insects serve as indicators of environmental health, nevertheless, the recent spate of human encroachment on wetlands is likely to affect its unique biotic composition, and this phenomenon poses a threat to the wetland environment. The physical and chemical quality of studied habitats in this research provided background information for comparison against the established quality standard of the wetland environment. The study involved reconnaissance surveys, insect trapping and social surveys on the impact of anthropogenic activities on insect diversity and abundance in and around the wetland environment. Twenty-two insect orders belonging to 112 families were sampled from different sites along the Sakumono, Kpeshie, and Muni-Pomadze wetlands. Species diversity and abundance were significantly different among the various locations with the most diverse being Kpeshie. Water within wetlands in Kpeshie was the most polluted although it had a positive correlation with insect diversity and abundance. Results of a survey of selected communities showed that majority of the residents had a low level of education with less appreciation of issues involving the environment including pollution. Majority of people within the surveyed communities were unable to access decent toilet facilities and publicly demarcated waste disposal sites. There was no coordinated and concerted effort to manage these three wetlands two of which are designated Ramsar sites. Activities such as farming, discharge of domestic garbage, improper fishing practices, improper disposal of industrial and human waste are increasing the pollution risk of these wetland environments.

This study sought to assess the challenges and opportunities that come with climate change and variability impacts on maize farming in the Nkoranza South Municipality in the Transitional Zone of Ghana. The mixed method approach (qualitative and quantitative) was used in collecting the data. Rainfall data obtained from the Ghana Meteorological Agency (GMet) indicated that the dry cell between the major and minor rainy seasons was getting wetter and the two seasons were gradually merging whereas the first and last quarters of the year were getting drier over the last couple of decades. The situation over the last five years (2010-2015) had worsened as the amount of total rainfall had reduced by 22% compared to the 30 year period between 1960 and 1982. The results of the study showed that farmers had perceived changes in climate in the form of decreasing rainfall, rising air temperatures and seasonal changes in rainfall pattern which were affecting their maize farming operations. The major setbacks within the area were deficit in rainy days and intermittent erratic rainfall affecting maize production. The major opportunity available to farmers in the face of changing climate in this agroecological zone was cashew production. About 76.8% of the respondents had diversified into cashew farming as a result of rainfall failure and strong resistance of the cashew trees to changing and variable climate.

In a bid to enhance the integrity and health of selected network of ecosystems and effectively manage them in Sierra Leone, a baseline assessment of butterfly diversity of two wetland ecosystems Mamunta Mayosso Wildlife Santuary (MMWS) and Sierra Leone River Estuary (SLRE) affected by different environmental stressors was undertaken as part of the Sierra Leone Wetland Conservation Project (SLWCP). We hypothesised that different environmental stressors affect butterfly communities in wetlands in Sierra Leone and the higher the stress the lower the butterfly diversity in an area. Sampling was conducted via field identification by wing patterns, flight mode, direct counts along transects and charaxes trapping. A total of 2300 individuals representing 95 species of butterflies were recorded. Though butterflies were evenly distributed at both sites, MMWS recorded the highest richness and abundance of butterflies during both seasons. This observation is reported to be because of high environmental stressors such as mining, agriculture and pollution from factories in the SLRE. The results further show that MMWS is made up of a mosaic of different vegetation patches that support higher diversity of butterfly species. This study also reveals that anthropogenic activities have a negative impact on butterfly diversity.

Conservation biologists and ecologists often make use of models to identify important biotic and abiotic factors that constrain species distributions for conservation decisions to be taken. In line with such practices, we developed species distribution models for four localized, Cape Floristic Region (CFR) endemic, flightless, congeneric Euloryma grasshopper species. We chose this group as use of these models has been little explored for narrow range endemics with specific traits. Euloryma larsenorum and E. lapollai are associated with fynbos only, while E. umoja and E. ottei are both associated with fynbos and vineyards. We used the Maximum Entropy algorithm, which showed that vegetation type and soil characteristics were the most important environmental factors affecting local distribution of Euloryma species in the CFR. The models also showed that Euloryma species have a very narrow habitat suitability range in the CFR. We also showed that there are no significant differences in the distribution of species associated with fynbos only as well as those associated with both fynbos and vineyards. E. larsenorum and E lapollai are likely to be the most affected species in the event of further habitat transformation from fynbos to agricultural production. This is not likely to be the case for E. umoja and E. ottei which can tolerate agriculture environment, although they might survive both sets of environments in accordance with their life history traits.

Spodoptera frugiperda was considered an insect pest only in the Americas until its first report in African countries in 2016. In this study, farmers and agricultural officials in Ghana were interviewed on their perceptions and knowledge of the pest, on infestation and maize yield variations across years, and on management practices. Farms were inspected to determine the infestation level of 100 plants per hectare. Interviews revealed that farmers were familiar with the larval stages of this pest and noticed that the pest occurred throughout the year, but populations of S. frugiperda increased only during cropping seasons. Infestation levels reported by farmers in surveys were much lower in 2018 (30.38%) than in 2017 (80.92%). Farm inspections confirmed that infestation levels were much lower in 2018 (20.90%) than 2017 (73.70%). The belt formed by Guinea Savannah, Transitional Zone, and Semi-Deciduous Forest Agro-Ecological Zones (AEZs) recorded the highest infestations while the lowest were observed from the Sudan Savannah and Tropical Rain Forest AEZs. Insecticides were the most commonly used tactic to manage populations of this new pest. Maize yields increased across Ghana between 2013 and 2015 from 1.52 to 1.73 t/ha, decreased between 2015 and 2017 to 1.55 t/ha, and increased to 1.69 t/ha in 2018. The impact of fall armyworm injury to maize production is discussed.

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an invasive insect pest attacking maize in Ghana and sub-Saharan Africa countries. Biological control will need to be an important management strategy, and a first step was to identify potential natural enemies. Sampling was conducted in different localities of the 10 regions of Ghana from May to Nov 2017. A total of 1,062 larvae were collected from 106 maize farms, and the presence of natural enemies was recorded in 18 (17.0%) farms. Among natural enemies recorded, 7 species were parasitoids: Chelonus bifoveolatus Szpligeti, Coccygidium luteum (Brull), Cotesia icipe Fernandez, Meteoridea testacea (Granger), and Bracon sp. (all Hymenoptera: Braconidae), Anatrichus erinaceus Loew (Diptera: Chloropidae), and an undetermined tachinid fly (Diptera: Tachinidae). The parasitism rate was 3.58%. Three predator species were collected: Pheidole megacephala (F.) (Hymenoptera: Formicidae), Haematochares obscuripennis Stal, and Peprius nodulipes (Signoret) (both Heteroptera: Reduviidae). The 2 most abundant parasitoids were C. bifoveolatus and C. luteum with a relative abundance of 29.0% and 23.7%, respectively, and a parasitism rate of 1.04% and 0.85%, respectively. However, C. bifoveolatus was the most dispersed parasitoid, found in 6.6% of the inspected sites within all the agroecological zones of Ghana. This species is a good candidate as a biological control agent for fall armyworm in Africa. The predator that was most abundant (46.0%) and dispersed (3.8% of the farms) was P. megacephala.

This study sought to assess the challenges and opportunities that come with climate change and variability impacts on maize farming in the Nkoranza South Municipality in the Transitional Zone of Ghana. The mixed method approach was used in collecting the data. The results of the study showed that farmers had observed changes in climate in the form of decreasing rainfall, rising air temperatures and seasonal changes in rainfall pattern which were affecting their maize farming operations. The major setbacks within the area were deficit in rainy days and intermittent erratic rainfall affecting maize production. The reduction in rainfall was corroborated by data obtained from Ghana Meteorological Agency (GMet) which indicated that the dry cell between the major and minor rainy seasons was getting wetter and the two seasons were gradually merging whereas the first and last quarters of the year were getting drier for a couple of decades. The situation over the last five years had worsened as the amount of total rainfall had reduced by 22% compared to the 30year period between 1960 and 1982. The major opportunity available to farmers in the face of changing climate in this agroecological zone was cashew production. About 76.8% of the respondents had diversified into cashew farming.

The small mammal community at Kogyae Strict Nature Reserve (KSNR) in the Ashanti Region of Ghana were studied in two habitats during the wet and dry seasons to investigate seasonal changes in species richness, abundance, composition and diversity. Ninety-six individuals belonging to nine species were recorded in 720 trap-nights, giving overall trap-success of 13.33%. Species richness (Sr), trap-success (Ts) and relative abundance (Ra) were higher (Sr = 6 species; Ts = 23.1%; Ra = 86.5%) in wooded grassland than forest (Ra = 4 species; Ts = 3.6%; Ra = 13.5%). However, species diversity was higher (Shannon-Wiener index Hʹ = 1.157) in forest than in wooded grassland (Hʹ = 1.089). Mastomys erythroleucus dominated in wooded grassland (68%) and Hylomyscus alleni in forest (53.8%). The species composition was unique for both habitats, with Mus musculoides being the only species common to both habitats. Seasonal changes in community assemblages were evident in both habitats, with species richness, diversity and abundance of the dominant species being highest in the wet seasons. Sex-ratio was unity in both habitats, and remained fairly constant throughout the rainy and dry seasons. Breeding activity was evident all-year-round for most species, but peaked in the rainy season. Our findings are consistent with that of other studies in Ghana and elsewhere in the African subregion, highlighting the importance of rainfall to the ecology of tropical small mammals.

An inventory of species diversity of insects of the Muni-Pomadze Ramsar site, with special reference to species of conservation concern, was carried out as part of an evaluation of changes in the ecological character of the site, twenty years after designation. Samples were taken from two protected areas within the Ramsar site, in the wet (July), dry (January), and intermediate (June) seasons. Community diversity was characterized in terms of number of species accumulated, species richness, Shannon-Weiner indices of diversity, Pielou’s evenness, and Bray-Curtis similarity. A total of 134 families from 19 insect orders were recorded during the entire study period. Yenku Block A recorded the highest species richness (98) and the highest diversity index (14.97), corroborated by the highest Margalef index of 3.82 with a relatively even distribution of species (0.834) during the intermediate season, and recorded the lowest diversity (6.957) and species richness (41) during the dry season. On the whole, the Muni-Pomadzi Ramsar site showed a high diversity of insect species. The presence of species such as Junonia oenone and Papilio demodocus which are specialized in degraded habitats at Yenku Block A in large numbers is a clear indication of degradation of the forest, but the presence of forest species such as Salamis anacardii and Euphaedra crokeri is an indication that some parts of this reserve are still in good shape. A comparison of the butterfly species recorded with findings in a 1997 survey showed a marked increase in numbers from 75 to 130; this may be attributed to the habitat changes that have taken place at the site offering more diverse habitat types.

This study was to provide baseline information on patterns of coil usage, user acceptability and susceptibility levels of mosquito coils in some parts of Accra, Ghana. Three hundred and twenty questionnaires were administered to obtain information on knowledge and perception of respondents on the usage of mosquito coils. Adult Anopheles gambiae mosquitoes were tested for resistance to pyrethroid based mosquito coils using WHO standard protocol for testing household insecticide products. A total of 152 out of 320 respondents were direct users of coils. Close to 62% of this number frequently changes brands of coil they use. Over 61% of coil users indicated their willingness to continue to use coils even though there are adverse effects after use. Anopheles gambiae s.s. was the only species that was found in the study area. Mortalities of An. gambiae s.s. after exposure to coils were 37% for Angel ® , 37.5% for Lord ® and 15% for Heaven mosquito coil brands. More than half of the inhabitants in the area used coils to prevent mosquito bites. However, high levels of resistance was detected for all the three pyrethroid-based coils because West African kdr was detected in about 59% of samples of Anopheles gambiae s.s. that survived the exposure.

Kogyae Strict Nature Reserve, the only one in Ghana, was established to promote scientific research, particularly on how nature revitalizes itself after major disasters, and also to check the southward drift of the savannah grassland. This study presents the first comprehensive inventory of species composition and diversity of insects of the Reserve. Insects were surveyed between September 2011 and June 2012 to capture the end of the rainy season, the dry season and the peak of the wet season. Samples were taken from two sites within the Reserve, Dagomba and Oku using various sampling techniques including pitfall traps, malaise traps and sweep nets. Insect communities were characterized in terms of, 1) species richness estimators, 2) species richness, 3) Shannon-Weiner Index of Diversity, 4) Pielou’s evenness and 5) Bray-Curtis similarity. A total of 8147 individuals representing 135 families from 21 orders were recorded. This included 107 species of butterflies from 9 families and 20 species of dragonflies from 3 families. Oku recorded the highest species numbers (S = 63) and richness (d = 12.16) with a high evenness of species (J = 0.9377) during the peak of the wet season; and the lowest species numbers (S = 58) and Margalef’s index of (d = 10.14) in January. The highest Shannon diversity index of (H = 3.927) was recorded at Dagomba in January.

Sacred groves in Ghana have been adopted as one of the strategies to mitigate the loss of biodiversity. They are seriously under threat from anthropogenic activities. A six month survey of the butterfly fauna in the Abiriw and Odu mante sacred groves in the Akwapim North and South Districts, respectively of the Eastern Region of Ghana was conducted to characterize resident butterfly species diversity and abundance. The transect count method and charaxes traps were used to sample the butterflies. Analysis of butterfly diversity in these groves, which range in size fro m 400 m 2 to 250 m 2 , was used to evaluate their effectiveness in achieving conservation objectives. Co mmun ity diversity was characterized in terms of, (a) number of species accumulated versus sampling effort, (b) nonparametric richness estimates, (c) Simpson's and Shannon-Weiner Indices of Diversity, and (d) Co mplementarity of co mmunit ies. A total of 1169 ind ividual butterflies were trapped across all sites representing 89 species from 10 families. Butterfly species richness and evenness in the Abiriw g rove was higher than that of the Odumante grove, however, the Abiriw grove harboured a resident community that was not distinctive from the Odu mante grove. These findings add to the body of knowledge that indicates that large groves are the foundation of successful conservation programs. Nonetheless, it was observed that both groves harbour a number of species that appear vulnerable to dynamics of fo rest frag mentation based on changes in their relative abundance across sites. The findings are discussed in the context of potential indicator species and theoretical predictions of at-risk species.

Many human societies, rely on proceeds from mining of metals and fossil fuels for income generation as well as resource supplies from biodiversity. However, these mining activities are in conflict with and threaten the sustainable utilisation and conservation of biodiversity. We used butterflies, a known bioindicator species as surrogates to measure the level of change in vegetation within Tarkwa Gold Mines (TGM) in Ghana. Butterfly assemblages were sampled within the concession and characterised in terms of diversity indices and vegetation type. Transect counts, aerial netting and charaxes trapping were employed to assess butterfly assemblages. Results showed that although there were high records of degraded forest and savanna indicator species, the fairly high presence of deep forested species also shows that some forested areas within the concession are still in good condition. Recommendations are made to maintain forest blocks to serve as refugia for butterflies and urge management to institute measures to restore old and abandoned mined sites. We also recommend policy makers to enact laws that will ensure that, mining organisations lay down plans for sustainable mine operations and biodiversity conservation before being granted licenses to operate in Ghana.

Genetic and biological implications from interbreeding the Ghanaian okra and cassava biotypes of Bemisia tabaci (Gennadius), reared on eggplant, were studied in reciprocal crossing plans and crosses compared with parental generations using RAPD–PCR. Interbreeding did not affect fecundity of mated females and survival of F1 progeny. However, the sex ratio of the hybrid progeny was significantly male dominated (by 70% males) compared to purebred progeny of each biotype (>60% females) (P

Eleven new species of Rheotanytarsus Thienemann et Bause from Central America and Mexico are described: R. baculus sp. n., R. calacmulensis sp. n., R. foliatus sp. n., R. guanacastensis sp. n., R. hanseni sp. n., R. kusii sp. n., R. nuamae sp. n., R. scutulatus sp. n., R. subtilis sp. n., and R. thunesi sp. n. as males only and R. ramirezae sp. n. as male and pupae. Two species are redescribed: R. exiguus (Johannsen) as male, pupae and larvae; and R. meridionalis (Johannsen) as male only. Keys to males and known pupae of Central American and Mexican Rheotanytarsus are given.