Peak Population Research Articles

Detrital zircon U–Pb age constraints on the Meso-Tethys Ocean closure in SE Asia

Abstract The location of the Meso-Tethyan suture in SE Asia is ambiguous due to the strong overprint by the later India–Asia collisional tectonics. For the SE Asian extension of the Meso-Tethyan Bangong–Nujiang Suture (BNS) in Tibet, the two main candidates are the Longling–Ruili Suture (between the Tengchong and Baoshan blocks) and the Myitkyina ophiolite belt. Here, we present new detrital zircon U–Pb ages from high-grade metasedimentary rocks of the Gaoligong Group, which is considered to be the basement of the Tengchong Block located between the Longling–Ruili Suture and Myitkyina ophiolite belt. Our data suggest that the Gaoligong Group contains Cambrian, Triassic and Cretaceous zircons and is not a Precambrian basement, with a diagnostic age population peak at c. 1110 Ma. This peak is comparable to the c. 1170 Ma peak reported in the Australia-derived blocks (e.g. Lhasa and West Australia). Such similarities, as well as the similarities in the stratigraphy, palaeobiogeography and magmatic history of the Tengchong Block, suggest that the Tengchong Block was located adjacent to the northern Australia margin in Gondwana, and was most likely to have been linked with the Lhasa Block (southern Tibet) since the Early Paleozoic. Thus, the Longling–Ruili Suture is likely to represent a continuation of the Meso-Tethyan BNS in SE Asia.

Indian sugarcane under warming climate: A simulation study

Multi-model climate projections are increasingly used to quantify the impacts of climate change on major staple crops under different climate change scenarios. Despite uncertainty associated with different climate projections, it helps in providing a direction and magnitude of change in crop production in future with different uncertainty levels. In this study, we used the CANEGRO-Sugarcane crop model driven by downscaled and bias-corrected simulations forced by different regional climate models (RCMs) for the mid-future (2040–2069) and far-future (2070–2099) under the two emission scenarios RCP4.5 and RCP8.5 to simulate the effect of climate change on sugarcane’s stalk fresh mass (SFM) and Sucrose Mass (SM) over major sugarcane growing states of India. The result showed, out of three phenological phases analyzed, two were found to be Shortened (planting to emergence up to 14.5 days and emergence to stalk elongation up to 6.3 days) and one i.e., peak population to harvest get extended up to 9.5 days under RCP8.5, far-future. An increase in SFM is projected substantially in the mid-future under RCP 8.5 for the tropical state of Gujarat (11.2–18.1 %) and the least for Odisha (6.8 % to 10.7). On the contrary, SM was found to decrease overall except for the states of Uttar Pradesh, Maharashtra, Gujrat, and Andhra Pradesh. The changes in the SFM and SM were found to be regulated by the increase in maximum (Tmax) and minimum temperature (Tmin), decline in solar radiation (Srad), leading to an increase in SFM and a reduction in sugar content. Therefore, decline in SM in the future which may cause economic loss as sugarcane is one of the most important cash crops of India. With uncertainties in the magnitude of change, the findings are useful for plant breeders and policymakers to develop appropriate strategies to minimize the loss and enhance sugar production.

Maternal Immune Activation by Polyinosinic-Polycytidylic Acid Exposure Causes Cerebral Cortical Dysgenesis through Dysregulated Cell Cycle Kinetics of Neural Stem/Progenitor Cells

Maternal immune activation reportedly causes dysregulation of the cell cycle in stem cells and impairment of higher cortical function in rodents. Furthermore, in humans, maternal immune activation during the first to second trimester of pregnancy is strongly correlated with increased incidence of autism spectrum disorder in the offspring. Here, we show that in utero exposure to polyinosinic-polycytidylic acid (poly (I:C)) in mice during the early phase of neuronogenesis increases the probability of differentiation (quiescent fraction [Q fraction]) of neural stem/progenitor cells (NSPCs) without change in the length of cell cycle. This abnormal increase in the Q fraction is assumed to reduce the peak population size of NSPCs, resulting in the thinning of the neocortex in offspring because of the reduced production of neurons. Furthermore, the neocortex of poly (I:C)-exposed mice does not exhibit a layer-specific reduction in radial thickness, possibly because of increased apoptosis caused by poly (I:C) exposure during all stages of cortical development. These results suggest that maternal immune activation by poly (I:C) exposure may affect neocortical histogenesis by altering the cell cycle kinetics of NSPCs. In addition, the timing and amount of poly (I:C) exposure during pregnancy may have profound effects on cerebral cortical histogenesis.

Developmental dynamics and survival characteristics of the common horse bot flies (Diptera, Gasterophilidae, Gasterophilus) in desert steppe

The genus Gasterophilus (Diptera, Gastrophilidae) is an obligate parasite of the equine family that causes widespread myiasis in desert steppe. Based on four common naturally excreted Gasterophilus larvae collected systematically in the Karamaili Ungulate Nature Reserve from March to September 2021, this paper studies the population dynamics and ontogenetic laws of horse flies, and discuss the coexistence pattern and population dynamics prediction of horse flies. The results showed that the Gasterophilus larvae had obvious concentrated development period, and the time of population peaks was different, the earliest was G. nigricornis (late March), followed by G. pecorum-Ⅰ (mid-April), G. nasalis (late April), G. intestinalis (early May), G. pecorum-Ⅱ (mid-August). The order of development threshold temperature “Cnigricornis < Cpecorum-Ⅰ ≤ Cpecorum-Ⅱ < Cnasalis < Cintestinalis” is consistent with the peak order of different larval populations. The life history survival rate (L) was as follows: Lnigricornis (83.97%) ≥ Lintestinalis (81.25%) > Lnasalis (72.42%) ≥ Lpecorum-Ⅱ (71.65%) > Lpecorum-Ⅰ (39.23%). This study combined indoor experiments and field surveys revealed the development of horse fly populations with different life strategies in desert grasslands. Based on the different development threshold temperatures of several horse flies, the staggered population dynamics of Gasterophilus form continuous infection stress on the host. In addition, G. pecorum exhibited a univoltine bimodal population distribution in this area and led to two high-intensity host infections, which is one of the important reasons why it has become the dominant species of myiasis in desert steppe.

Application of fermented bran and probiotics to enhance mass-scale production of Phronima sp. in the pond

This study aimed to evaluate the efficacy of utilizing probiotics and organic matter as nutrients for Phronima sp. mass cultures in ponds. Culture media, which had water depths of 40 cm was added to the pond plots (35×30×0.4 m), then sterilized and neutralized. Organic fertilizer (70 kg/1000 m2) was spread, and after 3 days the inorganic fertilizer was spread in the form of ZA (20 ppm), TSP (5 ppm), and NPK (5 ppm). Rice bran, a by-product of rice production, was fermented with molasses for a week, with a dosage of 1:0.25. Fermented bran mixed with probiotics (ratio of 1:1) was used as daily feed. Phronima sp. was spread with a density of 137 individuals/m2. The population density was monitored weekly. The test results showed that the growth pattern of Phronima sp. formed a sigmoid curve consisting of the lag phase, specific growth rate, population peak, and death phase. There was a significant population increase from the fourth to the seventh week, with a peak population density in the seventh week, reaching a density of 87,300 ± 6,526 individuals/m2. In the eighth week, the population density drastically decreased to only 10% of the peak.

Biology and seasonal population dynamics of the forest dung beetle Anoplotrupes stercorosus (Coleoptera: Geotrupidae) in the Center of European Russia

The biology and population dynamics of Anoplotrupes stercorosus was studied in forest ecosystems of central European Russia (2007-2023). During the study period, 6738 individuals were collected from 256 habitats. In open biotopes, Anoplotrupes stercorosus was caught only occasionally or no specimens were found at all. The species is most abundant in mixed forests with a pronounced shrub layer and grass cover, complex pine forests and deciduous forests. Seasonal population dynamics varies in different habitats. It can be with one, two or three population peaks. The possibility of using Anoplotrupes stercorosus as a bioindicator of forest ecosystem condition was studied. The abundance of the species was found to be very low on burned areas.

Population dynamics of walnut aphid, Chromaphis juglandicola Kaltenbach, 1843 (Hemiptera: Aphididae) on Juglans regia (Walnut) in Kashmir

Regarded as one of the economically important crops of Kashmir, walnut trees are vulnerable to insect pests and diseases leading to great economic losses every year, thus to have knowledge about various factors that leads to it, is indispensable. The objective of the present study was to evaluate the population dynamics in terms of abundance and distribution of Chromaphis juglandicola in response to biotic and abiotic factors. Sites were monitored for two years from January 2017 to December 2018, in which five trees were randomly selected from two sites and each site was visited fortnightly. The counted collected specimens were identified and sampling protocol was established by seasonal richness peaks. The data depicted that C. juglandicola showed definite seasonal trend with highest population in summer and lowest in autumn with peak population in the month of June. Further, it was observed aphidophagous coccinellids also played a significant role in controlling aphid population. Six beetles were reported during two years of study out of which Calvia punctata and Harmonia diamadata were most abundant.

Infestação da mosca-do-botão-floral e sua relação com aspectos morfológicos e fenológicos do maracujazeiro-azedo (Passiflora edulis) no sul de Santa Catarina

Abstract The objective of this work was to evaluate the infestation of the flower-bud-fly in different sizes of flower buds and to relate the infestation with the plant phenology and weather variables. In the 2017/18 and 2018/19 seasons, flower buds of plants were collected to obtain pupae, adults, and parasitoids in a commercial orchard of sour passion fruit, in Sombrio, state of Santa Catarina. The level of infestation, pupal viability, and percentage of parasitism were calculated. Every fortnight, the vegetative and reproductive structures of 12 orchard plants (0.25 m² per plant), randomly distributed, were monitored, as soon as they reached the height of the trellis. Three population peaks of the floral bud fly were observed in the seasons, which preferred to oviposit in buds larger than 2 cm. The critical period for pest monitoring and control occurred between November and December. The average temperature and precipitation were the main factors that influenced the production of sour passion fruit. The average temperature was correlated with the emission of flower buds and the emergence of lonqueids. D. inedulis was the predominant species in flower buds, in which Dasiopssp.1, Dasiops sp. 2, and Neosilba certa were reported for the first time. It was also the first report of Utetes anastrephae and Aganaspis pelleranoias parasitoids of larvae-pupae of the flower bud fly of the sour passion fruit tree in Santa Catarina.

An extended Susceptible-Exposed-Infected-Recovered (SEIR) model with vaccination for forecasting the COVID-19 pandemic in Sri Lanka

Background: After declaration of a Public Health Emergency of International Concern (PHEIC) by the World Health Organization, Novel Corona Virus had been spreading throughout the world despite various degrees of movement restrictions and availability of multiple safe and effective vaccines. Vaccination rate against COVID-19 is one of the infection rate’s main determinants. The role of modelling in predicting the spread of an epidemic is important for health planning and policy making.Objective: This study aimed to construct a compartmental epidemiological model incorporating vaccination coverage, vaccination rate, vaccine efficacies and applied a computational tool for predicting the evolution of different epidemiological variables for COVID-19 in Sri Lanka.Methods: We used a dynamic Susceptible-Exposed-Infected-Recovered-Vaccinated (SEIRV) model and simulated potential vaccine strategies under a range of epidemic conditions. The predictions were based on different vaccination coverages (5% to 90%), vaccination-rates (1%, 2%, 5%) and vaccine-efficacies (40%, 60%, 80%) under different R0 (2,4,6). We estimated the duration, exposed, and infected populations.Results: When the R0 was increased, the days of reduction of susceptibility and the days to reach the peak of the infection were reduced gradually. At least 45% vaccine coverage is required for reducing the infected COVID-19 population to mitigate a disastrous situation in Sri Lanka.Conclusion and recommendations: The results revealed that when R0 is increased in the SEIRV model along with the increase of vaccination efficacy and vaccination rate, the population to be vaccinated is reducing. Thus, the vaccination offers greater benefits to the local population by reducing the time to reach the peak, exposed and infected population through flattening the curves. The prediction models will lead to policy relevance despite the significant uncertainty associated with real-time forecasting in complex systems with timely predictions and steadfast reports.

비가림 재배 유기농 한라봉 감귤원에서 썩덩나무노린재의 연간 발생양상

The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is polyphagous pest insect, originated in East Asia including Korea, China, Japan and Taiwan, injuring leguminous and fruit plants and many ornamental trees. Usually stink bugs need legumes as food to complete their life cycle. In particular, in Jeju, the damage of H. halys is frequently found in the environment-friendly citrus cultivation, thus, this study was conducted to find out whether the full life history of H. halys can be completed in an organic citrus orchard with non-heated cultivated greenhouse. In organic ‘Shiranui’ (brand name Hallabong ((Citrus unshiu x C. sinensis) x C. reticulata)) orchard grown in non-heated greenhouse, seasonal fluctuation of each developmental stages of H. halys and its preferring host sites were investigated by visual counting method. The adult population peaks (summer generation) occurred in mid-July for the first generation and late-October for the second generation. Most H. halys was found on young leaves of shoots before fruit coloring (September) with few-individuals were observed on fruits, while thereafter the fourth to fifth nymphs of H. halys moved to citrus fruits for feeding resulting in the fruit drop. Consequently, it was found that H. halys can complete its life cycle in the citrus without special legumes.

SEASONAL INCIDENCE OF MAJOR INSECT PESTS OF RICE IN KRISHNA WESTERN DELTA REGION OF GUNTUR DISTRICT

The seasonal occurrence of major insect pests of rice in Guntur district of Andhra Pradesh during kharif 2021-22 was studied in Krishna Western Delta area in 90 farmers fields of 10 mandals (Bapatla, Kakumanu, Ponnur, Tsunduru, Amruthaluru, Vemuru, Tenali, Duggirala, Repalle and Nagaram). Fortnightly observations on pest population in parallel relation with meteorological parameters revealed the highest leaf damage due to rice leaf folder Marasmia medinalis (Crambidae: Lepidoptera)during second fortnight of September (2.95%) when the crop was more succulent. The incidence of yellow stem borer Scirpophaga incertulas (Crambidae: Lepidoptera) begun appearing during first fortnight of August with highest percent damage during second fortnight of September causing 2.62 percent dead hearts. The peak population of brown planthopper Nilaparvata lugens (Delphacidae: Hemiptera) was observed during first fortnight of October (4.97 hoppers/hill) when the crop was in panicle initiation stage.

SCREENING OF AFRICAN AND FRENCH MARIGOLD GERMPLASMS AGAINST Tetranychus urticae KOCH (ACARI: TETRANYCHIDAE) UNDER FIELD CONDITIONS

The germplasms of African and French marigold were screened at Research Farm Area, Department of Horticulture, CCS Haryana Agricultural University, Hisar, Haryana against the two spotted spider mite, Tetranychus urticae (TSSM) in the winter season from first week of October to first week of March, 2018. The germplasm tall orange African sheltering lowest mite population (9.82 mites/leaf) was marked as the least susceptible and Hisar Jafari-2 French with 32.21 mites/leaf was categorized as highly susceptible for T. urticae infestation. Mite population was recorded weekly and significantly higher number of mites was recorded on grown up leaves followed by tender and older leaves of marigold plants. Irrespective of the germplasm, the mite number was found to significantly increase with each observation period till the attainment of peak in population in the month of January (35.51 mites/ leaf) while their least population was recorded in the month of October (6.65 mites/leaf). In general, French germplasms were comparatively more susceptible to T. urticae infestation as compared to African germplasms.

Seasonal abundance of major insect pests of potato (Solanum tuberosum) and their natural enemies in Karnataka, India

It is essential to know the seasonal occurrences of various pests of potato along with their natural enemies so that timely management practices could be advised to farmers to avoid losses. Therefore, field studies on seasonal incidence of major insect pests of potato and their natural enemies were carried out at the All India Co-ordinated Research Project on Potato, Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, India during Kharif 2016 and 2017; and at Hangaraki, a village near Dharwad during Rabi 2016-17 and 2017-18. The observations on the seasonal abundance of potato insects, mites, and their natural enemies were recorded at weekly intervals starting from 20 days after the emergence of the plant till harvest. These observations were made under unprotected conditions. During Kharif season, the sucking pests were active from July second week and continued up to harvesting of the crop and the maximum pest population was observed during August second week to September first week. The peak activity of the shoot borer, Leucinodes orbonalis Guenee was noticed during the 35th Meteorological Standard Week (MSW) (i.e., August). The maximum population of defoliator, Spodoptera litura (Fab.) was noticed during 34th MSW. The higher populations of coccinellid beetles and spiders were recorded during 35th MSW while chrysopid activity was maximum during 36th MSW (September). During Rabi season, the sucking pests were active from October second week and attained peak during the second and third week of November. The maximum activity of aphids and leafhoppers was noticed during the 46th and 47th MSW (November), respectively. The highest incidence of thrips was recorded during the 48th MSW. The peak population of whiteflies and mites was recorded during the 46th and 45th MSW, respectively. The peak activity defoliator and shoot borer were noticed during the 45th and 46th MSW, respectively. The chrysopid activity was maximum during 46th and 47th MSW.

Reconstructing midge consumer-resource dynamics using carbon stable isotope signatures of archived specimens.

Population cycles can be caused by consumer-resource interactions. Confirming the role of consumer-resource interactions, however, can be challenging due to an absence of data for the resource candidate. For example, interactions between midge larvae and benthic algae likely govern the high-amplitude population fluctuations of Tanytarsus gracilentus in Lake Mývatn, Iceland, but there are no records of benthic resources concurrent with adult midge population counts. Here, we investigate consumer population dynamics using the carbon stable isotope signatures of archived T. gracilentus specimens collected from 1977 to 2015, under the assumption that midge δ13 C values reflect those of resources they consumed as larvae. We used the time series for population abundance and δ13 C to estimate interactions between midges and resources while accounting for measurement error and possible preservation effects on isotope values. Results were consistent with consumer-resource interactions: high δ13 C values preceded peaks in the midge population, and δ13 C values tended to decline after midges reached high abundance. One interpretation of this dynamic coupling is that midge isotope signatures reflect temporal variation in benthic algal δ13 C values, which we expected to mirror primary production. Following from this explanation, high benthic production (enriched δ13 C values) would contribute to increased midge abundance, and high midge abundance would result in declining benthic production (depleted δ13 C values). An additional and related explanation is that midges deplete benthic algal abundance once they reach peak densities, causing midges to increase their relative reliance on other resources including detritus and associated microorganisms. Such a shift in resource use would be consistent with the subsequent decline in midge δ13 C values. Our study adds evidence that midge-resource interactions drive T. gracilentus fluctuations and demonstrates a novel application of stable isotope time-series data to understand consumer population dynamics.

Exploring GI Diseases Across the Lifespan.

Exploring GI Diseases Across the Lifespan.

Spatial Matching and Policy-Planning Evaluation of Urban Elderly Care Facilities Based on Multi-Agent Simulation: Evidence from Shanghai, China

China is about to enter the stage of deep aging, and the number of disabled elderly is growing continuously. Although the government continues to increase its investment in elderly care institutions and facilities, there is still an unreasonable and unbalanced structure of resource allocation, and the configuration of elderly care institutions and facilities is not well coupled with the geographical layout of the population. Taking Shanghai, China, as an example, based on the multi-agent simulation method, this paper forecasts the supply and demand of elderly care institutions, and evaluates the rationality of relevant policy planning by comprehensively analyzing the behavior of the elderly, the behavior of elderly care institutions, and the interaction between the actors and the environment. The study concludes that: (1) With the increase of aging in Shanghai, the disability rate and chronic diseases will reach 18.7% and 42.0%, respectively, before the arrival of the peak of the elderly population in 2030, and 32.2% of the elderly will be willing to receive nursing services in elderly care institutions, which may make it difficult for the incremental reform of institutional beds in the existing policy planning to meet the actual needs. (2) The index of the number of beds for 100 people in the spatial configuration of elderly care institutions continued to increase, but the actual utilization rate of beds continued to decline, which was only 61.3% in 2030. (3) From the regional perspective, there is an obvious imbalance. The research shows that, with the increase in the disability rate of the elderly and the high incidence of chronic diseases, increasing the supply of facilities for elderly care institutions is an inevitable choice to meet the differentiated needs of the elderly. The demographic characteristics, psychology, economic costs, and spatial distribution of the elderly have a comprehensive impact on the decision-making of institutional elderly care. Institutional facility planning needs to combine urban development strategies, comprehensively consider economic costs, population characteristics and spatial distribution, and achieve a reasonable layout of different types of elderly care institutions. In summary, this paper provides a reference for the scientific layout of urban elderly care institutions through multi-agent simulation, and provides empirical support for how to achieve a good configuration of “population–facilities” in space.

Covid-19-associated rhino-orbito-cerebral mucormycosis (CAROM) in Delhi: Demographics and risk factors in a single-centre consecutive cohort of 200 inpatients

Background There was a dramatic rise in the incidence of rhino-orbito-cerebral mucormycosis associated with the 2021 Covid-19 wave in India. We aim to document the demographic characteristics and risk factors of a consecutive cohort of inpatients with Covid-19-associated rhino-orbito-cerebral mucormycosis (CAROM) during the surge of April-June 2021. Methods We included all patients of CAROM treated at our tertiary referral facility from 1 April to 14 June 2021. We prospectively gathered details with regard to Covid-19 illness and treatment, CAROM presentation, comorbid conditions and risk factors. Results Our prospective cohort consisted of 200 consecutive patients, of which 146 (73%) patients tested positive on the Covid-19 RT-PCR test at presentation. CAROM occurred concurrent with the Covid-19 infection in 86%, and delayed CAROM after seeming recovery from Covid-19 was seen in 14%. Covid-19 was classified as mild, moderate and severe in 54%, 33% and 13%. The surge of CAROM followed the population peak of Covid-19 infections by about 3 weeks. Advanced disease at presentation was frequent with ocular involvement in 56.6% (111/196) and central nervous system involvement in 20% (40/199). One or more comorbid conditions were identified in 191/200 (95.5%) patients. The dominant associations were with diabetes (189/200; 94.5%) and uncontrolled hyper-glycaemia (122/133; 91.7%), recent steroid use (114/ 200; 57%), which was often considered as inappropriate in dosage or duration, lymphopenia (142/176; 80.7%), and increased ferritin levels (140/160; 87.5%). No evidence supported the role of previous oxygen therapy or previous nasal swab testing as risk factors for CAROM. Conclusion The inpatient volumes of CAROM were noted to parallel the Covid-19 incidence curve by about 3 weeks. Covid-19 infection may directly predispose to CAROM by way of lymphopenia and increased ferritin levels. Uncontrolled hyperglycaemia is identified as a near-invariable association. Recent steroid use is noted as very frequent and was often received in excess of treatment advisories.

Studies on seasonal population fluctuations and feeding damage induced by Dolichotetranychus floridanus (Banks) (Acari: Tenuipalpidae) on areca palms of Kerala, India

The state of Kerala is home to nearly 10,035 plant species as per the diversity scenario, thereby constituting 22% of the total plant diversity of India. Areca catechu L. (Arecales: Arecaceae) is an important plantation crop of Kerala with a multitude of economic utility and constitutes an important source of income for the people. The areca palms of Kerala are under the threat of many arthropod pests, of which tenuipalpid mites represent a major group causing severe damage to the foliage as well as the nuts. The present study reports a new host record for the tenuipalpid species viz Dolichotetranychus floridanus, which was found to infest the areca palms inducing severe damage to the developing nuts in various Areca plantations of Kerala. To understand the extent of damage induced by the species to its new host A. catechu, sampling was carried out monthly to collect nut samples from areca plantations distributed in two districts viz. Kozhikode and Malappuram of North Kerala, for a period of two years from 2013 and 2015. The collected nut samples were examined in the laboratory under a stereozoom microscope (MVNSZ-450) and data were collected on the population density of the mite as well as the qualitative aspects of feeding damage induced by the mite on the nuts. Results of population studies enabled to record peak population density of D. floridanus during July–August months. A positive correlation was found to exist between mite population and relative humidity and a negative correlation was recorded between mite population and temperature. The mean longevity of the females of this species at different temperatures and humidity conditions was recorded as 17.64 ± 0.17 days at 25 + 2oC &amp; 80 + 5% RH, 13.64 ± 0.12 days at 30 + 2oC &amp; 70 + 5% RH and 11.37 ± 0.12 days at 35 + 2oC &amp; 60 + 5% RH. The feeding activity of the species was found to induce severe alterations, leading to the drying up of epidermal tissue, and formation of cracks at the affected region and the latter often served to permit the entry of fungal and bacterial pathogens, leading to tissue rot.

The eradication of cattle from Enderby Island and subsequent ecological response

Cattle (Bos taurus) were liberated on 695 ha Enderby Island, the northernmost of the Auckland Island group, in 1894–96, after a previous liberation had died out. After reaching a peak population of c. 100 animals, they established a relatively stable population of 35–60 animals for the latter half of the 20th century.

Tephritid Fruit Fly Species Composition, Seasonality, and Fruit Infestations in Two Central African Agro-Ecological Zones.

Bactrocera dorsalis and several Africa-native Ceratitis species are serious constraints to fruit production in sub-Saharan Africa. A long-term trapping and fruit collection study was conducted (2011-2016) in two contrasting agro-ecological zones (AEZs) of Cameroon to determine fruit fly species composition, seasonality, attraction to various lures and baits, and fruit infestation levels. Ten tephritid species from genera Bactrocera, Ceratitis, Dacus, and Perilampsis were captured in traps. Bactrocera dorsalis was the most dominant of the trapped species and persisted throughout the year, with peak populations in May-June. Ceratitis spp. were less abundant than B. dorsalis, with Ceratitis anonae dominating in the western highland zone and Ceratitis cosyra in the humid forest zone. Methyl eugenol and terpinyl acetate captured more B. dorsalis and Ceratitis spp., respectively than Torula yeast. The latter was the most effective food bait on all tephritid species compared with BioLure and Mazoferm. Bactrocera dorsalis was the dominant species emerging from incubated fruits, particularly mango, guava, and wild mango. Four plant species-I. wombolu, Dacryodes edulis, Voacanga Africana and Trichoscypha abut-were new host records for B. dorsalis. This study is the first long-duration and comprehensive assessment of frugivorous tephritid species composition, fruit infestations, and seasonality in Central Africa.