African Lakes Research Articles

Prostorové rozložení ložisek nerostných surovin těžených artisanální těžbou v oblasti východoafrických velkých jezer

The East African Great Lakes Region is an area rich in rare mineral resources and thus represents a great economic potential. Mineral mining in Great Lakes Region is proceeding in a specific way which is known as artisanal and small-scale mining. This mining with no mechanization is mostly expanding in developing countries. In these areas mining represents one of the main sources of income for the local population and creates one of the main pillars of economic development. This paper presents the artisanal and small-scale mining and spatial distribution of mineral deposits in Burundi, Kenya, Rwanda, Tanzania and Uganda where rare minerals are extracted. The aim of this article is to introduce artisanal and small-scale mining to Central Europe discussion where this topic is relatively neglected. Minerals which are extracted by artisanal and small-scale mining are used in electro-technical industry, i.e. mobile phones, computers, tablets, automobiles, aircrafts and other technical products manufacturing, the extracted minerals become significant and direct part of our everyday life.

Rapid response of fossil tetraether lipids in lake sediments to seasonal environmental variables in a shallow lake in central China: Implications for the use of tetraether-based proxies

Bacterial branched and archaeal isoprenoid glycerol dialkyl glycerol tetraethers (brGDGTs and isoGDGTs, respectively) have become important tools for the paleoclimate reconstruction of lacustrine systems. However, it is still unclear how geochemical proxies based on GDGTs, particularly in lake surface sediments, respond to seasonal environmental changes in shallow water lakes, whose sediment cores are increasingly being used for paleoenvironmental reconstruction. In this study, we collected samples from the top 0–2 cm of sediments and water column suspended particulate matter (SPM) at a monthly interval from June 2015 to May 2016 in Lake Donghu, a shallow lake in central China. An updated liquid chromatography method was used to separate the 5- and 6-methyl brGDGTs. A remarkable difference between the lake sediments, SPM, and catchment soils suggested that microorganisms inhabiting the surface sediments contributed a significant proportion of isoGDGTs and brGDGTs to the GDGT pool in the lake sediments. We found a clear seasonality in the concentration and distribution of core lipid (CL) isoGDGTs and brGDGTs in the lake surface sediments, in contrast to the absence of seasonality in brGDGTs in mid-latitude soils reported by previous studies. The intact polar lipid/CL ratios for both isoGDGTs and brGDGTs in the lake surface sediments were significantly higher than those in SPM and catchment soils and were higher in the warm seasons than in winter. This collectively suggested that the turnover of brGDGTs in the lake sediments was faster than that in soils. Furthermore, the GDGT-0/Cren ratio for the lake sediments exhibited a negative correlation with dissolved oxygen in the water column. The cyclisation degree of C5-methylated brGDGTs (CBT5ME) was strongly related to water pH. Seasonal temperature variation clearly impacted the methylation degree of C6-methylated brGDGTs (MBT′6ME) but had no influence on C5-methylated brGDGTs (MBT′5ME), as opposed to the dependence of MBT′5ME on temperature in global soils, peatlands and African lakes. Due to the fast turnover rate and the sensitive response to seasonality, we suggest that the seasonal variation of fossil GDGTs in lake sediments should be considered when developing a calibration using fossil GDGTs in shallow-water lake surface sediments.

International mineral trade on the background of due diligence regulation: A case study of tantalum and tin supply chains from East and Central Africa

Over the past eight years, due diligence has become an increasingly important component of supply chain management for “conflict minerals” such as tantalum and tin. The due diligence concept has been incorporated into regulatory requirements and industry standards as far as mineral sourcing from the Democratic Republic of the Congo (DRC) and the wider East-Central African Great Lakes region is concerned. The present study investigates how this development is reflected in the trade data of tantalum and tin ore concentrates sourced from the region. The analysis is based on international import data reported by smelter countries covering the 2006–2017 period and calibrated against a supply chain framework of regionally aggregated tantalum and tin producer and transit countries. International imports of tantalum and tin ore concentrates from the Great Lakes region show correlated trends for both commodities comprising a pre-regulatory period from 2006 to 2009, a transitional period of initial due diligence implementation from 2010 to 2012, and an on-going period of streamlined due diligence implementation starting in 2013. Tantalum and tin import reductions in 2010–2011 correlate in time with publication of the conflict mineral section of the Dodd-Frank act in the United States, a temporary ban of artisanal and small-scale mining in the DRC and a de facto embargo established by a number of international mineral buyers. Following a two-year transitional period, international tantalum and tin ore concentrate imports from the region progressively recover towards and beyond pre-Dodd-Frank act levels. The market structure of smelter countries sourcing tantalum from the region changes from a China-dominated monopsonistic situation prevailing from 2006 to 2012 towards a less concentrated international market in 2013–2017. This development correlates with the region's increasing world market share in tantalum mine production. In contrast, tin supply chains reflect an oligopsonistic market that does not change systematically through time. While aggregated international import and regional export data for tantalum and tin ore concentrates used to show strong discrepancies in the past, these data are in good agreement from 2013 onward. Mineral origin declarations show progressively increasing geological and logistical plausibility likely reflecting a reduction of intra-regional smuggling and more accurate chain of custody documentation. As such, international mineral trade data become more consistent with on-going implementation of due diligence.

Public Health in Southwest Uganda: Religion, Community, and Healing

In this region of far southwestern Uganda, where the borders of Uganda, Congo, and Rwanda converge like a tricuspid valve of the East African Great Lakes Region, a person requiring medical assistance has three basic options. They may consult (1) traditional healers, (2) travel to the Bwindi Community Hospital, or (3) seek assistance at government health facilities. Proximity to health facilities, economic means, topography, and spiritual factors influence the decision a person makes. Our purpose here today — and I am here speaking on behalf of myself and my co-researcher, Namanya Sezi Busingye — is to report on qualitative findings in Bwindi most relevant to the relationship between the Bwindi Community Hospital and traditional healers within the context of public health in this region.

The 2017 African Great Lakes Conference: Conservation and development in a changing climate

Abstract In May 2017, the African Great Lakes community convened for a region-wide conference in Entebbe, Uganda. The African Great Lakes Conference (AGLC) focused on 6 regionally-important themes, and 300+ attendees presented over 100 talks and posters. The AGLC culminated in the adoption of a set of Conference Resolutions designed to direct the future of African Great Lakes conservation and management. As an Introduction to this Journal of Great Lakes Research special section on African Great Lakes, we report on the impetus for the African Great Lakes Conference as well as discuss three major advances and investments that were a direct result of conference resolutions adopted at the meeting. First, we present the AGLC Resolutions, a set of management issues and solutions developed at the conference. Second, we discuss the African Great Lakes Conference Fund, a conservation fund that has awarded $500,000 USD to launch four new initiatives. Finally, we describe African Great Lakes Inform, a knowledge management platform designed to promote collaboration in the region. The AGLC in general, and these three major conference outcomes specifically, provide a set of basic building blocks to advance partnerships, research and capacity in the African Great Lakes region.

Delineating species along shifting shorelines: Tropheus (Teleostei, Cichlidae) from the southern subbasin of Lake Tanganyika

BackgroundSpecies delineation is particularly challenging in taxa with substantial intra-specific variation. In systematic studies of fishes, meristics and linear measurements that describe shape are often used to delineate species. Yet, little is known about the taxonomic value of these two types of morphological characteristics. Here, we used Tropheus (Teleostei, Cichlidae) from the southern subbasin of Lake Tanganyika to test which of these types of characters best matched genetic lineages that could represent species in this group of stenotypic rock-dwelling cichlids. We further investigated intra-population variation in morphology. By linking this to a proxy of a population’s age, we could assess the evolutionary stability of different kinds of morphological markers.ResultsMorphological data was collected from 570 specimens originating from 86 localities. An AFLP approach revealed the presence of five lineages in the southern subbasin: T. moorii, T. brichardi, T. sp. ‘maculatus’, T. sp. ‘Mpimbwe’ and T. sp. ‘red’, which we consider to represent distinct species. Although both types of morphological data supported this classification, a comparison of PST-values that describe inter-population morphological differentiation, revealed a better correspondence between the taxon delineation based on AFLP data and the patterns revealed by an analysis of meristics than between the AFLP-based taxon delineation and the patterns revealed by an analysis of shape. However, classifying southern populations of Tropheus was inherently difficult as they contained a large amount of clinal variation, both in genetic and in morphological data, and both within and among species. A scenario is put forward to explain the current-day distribution of the species and colour varieties and the observed clinal variation across the subbasin’s shoreline. Additionally, we observed that variation in shape was larger in populations from shallow shores whereas populations from steep shores were more variable in meristics. This difference is explained in terms of the different timescales at which small and large scale lake level fluctuations affected populations of littoral cichlids at steep and shallow shores.ConclusionsOur results showed meristics to be more evolutionary stable, and of higher taxonomic value for species delimitation in Tropheus, than linear measurements that describe shape. These results should be taken into account when interpreting morphological differences between populations of highly stenotypic species, such as littoral cichlids from the Great East African Lakes.

Constraints on Rift Basin Structure and Border Fault Growth in the Northern Malawi Rift From 3‐D Seismic Refraction Imaging

AbstractWe present new constraints on rift basin structure in the northern Malawi Rift from a 3‐D compressional velocity model to investigate border fault geometry, accommodation zone structure, and the role of preexisting structures underpinning this rift system. The velocity model uses observations from the first wide‐angle refraction study conducted using lake‐bottom seismometers in one of the East African great lakes. The Malawi Rift is flanked by basin‐bounding border faults and crosses several significant remnant structures, making it an ideal location to investigate the development of normal faults and their associated basins. The 3‐D velocity model reveals up to ~5 km of synrift sediments, which smoothly transition from eastward thickening against the Livingstone Fault in the North Basin to westward thickening against the Usisya Fault in the Central Basin. Greater than 4 km of sediment are imaged within the accommodation zone pointing to the early development of the border faults. We use new constraints on synrift sediment thickness to construct displacement profiles for both faults. Both faults accommodate large throws (>7 km) consistent with their significant lengths. The dimensions of these faults are close to or larger than the maximum size predicted by models of fault growth. The presence of an intermediate velocity unit with velocities of 3.75–4.5 km/s is interpreted to represent sediment deposits beneath Lake Malawi from prior rifting in the Permo‐Triassic (Karoo) and/or Cretaceous‐Paleogene. The distribution of preexisting basins implied by these sediments may help account for changes in intrabasinal faulting and border fault development between the two basins.

From shallow to deep divergences: mixed messages from Amazon Basin cichlids

Cichlids are a conspicuous component of Amazonian ichthyofauna, filling a wide range of niches. Yet taxonomy of many groups is still poorly known in the Amazon, and most of the yet-to-be discovered species are concentrated there. We analyzed 230 individuals sampled from six major Amazonian River Basins representing 56 morpho-species, 34 nominal and 22 undescribed species in 18 cichlid genera. We used four different single-locus species-discovery (SLSD) methods, delimiting between 53 (mPTP) and 57 (GMYC) species/lineages. When detected, species/lineages are hierarchically geographically structured. Many groups such as the Geophaginae and the Cichlinae have recently diversified, and species of genera such as Cichla and Symphysodon hybridize or have a history of hybridization; thus, these species will not be detected by SLSD methods. At the same time, for example, the genera Apistogramma and Biotodoma harbor cryptic species. For all these reasons, species/lineage diversity of Amazonian cichlids is significantly underestimated. The diversity of Amazonian cichlids is particularly remarkable given that the 570 species of Neotropical cichlids, many of which are from the Amazon Basin, are found in just 1.7% of the freshwater aquatic habitat in which the ~ 2,000 species of the East African rift lake cichlids evolved.

Molecular and Cytogenetic Study of East African Highland Banana.

East African highland bananas (EAHBs) are staple food crop in Uganda, Tanzania, Burundi, and other countries in the African Great Lakes region. Even though several morphologically different types exist, all EAHBs are triploid and display minimal genetic variation. To provide more insights into the genetic variation within EAHBs, genotyping using simple sequence repeat (SSR) markers, molecular analysis of ITS1-5.8S-ITS2 region of ribosomal DNA locus, and the analysis of chromosomal distribution of ribosomal DNA sequences were done. A total of 38 triploid EAHB accessions available in the Musa germplasm collection (International Transit Centre, Leuven, Belgium) were characterized. Six diploid accessions of Musa acuminata ssp. zebrina, ssp. banksii, and ssp. malaccensis representing putative parents of EAHBs were included in the study. Flow cytometric estimation of 2C nuclear DNA content revealed small differences (max ~6.5%) in genome size among the EAHB clones. While no differences in the number of 45S and 5S rDNA loci were found, genotyping using 19 SSR markers resulted in grouping the EAHB accessions into four clusters. The DNA sequence analysis of the internal transcribed spacer region indicated a relation of EAHB clones with M. acuminata and, surprisingly, also with M. schizocarpa. The results suggest that EAHB cultivars originated from a single hybrid clone with M. acuminata ssp. zebrina and ssp. banksii being its most probable parents. However, M. schizocarpa seems to have contributed to the formation of this group of banana.

Only true pelagics mix: comparative phylogeography of deepwater bathybatine cichlids from Lake Tanganyika

In the absence of dispersal barriers, species with great dispersal ability are expected to show little, if at all, phylogeographic structure. The East African Great Lakes and their diverse fish faunas provide opportunities to test this hypothesis in pelagic fishes, which are presumed to be highly mobile and unrestricted in their movement by physical barriers. Here, we address the link between panmixis and pelagic habitat use by comparing the phylogeographic structure among four deepwater cichlid species of the tribe Bathybatini from Lake Tanganyika. We show that the mitochondrial genealogies (based on the most variable part or the control region) of the four species are very shallow (0.8–4% intraspecific divergence across entire distribution ranges) and that all species experienced recent population growth. A lack of phylogeographic structure in the two eupelagic species, Bathybates fasciatus and B. leo, was consistent with expectations and with findings in other pelagic cichlid species. Contrary to expectations, a clear phylogeographic structure was detected in the two benthopelagic species, B. graueri and Hemibates stenosoma. Differences in genetic diversity between eupelagic and benthopelagic species may be due to differences in their dispersal propensity, mediated by their respective predatory niches, rather than precipitated by external barriers to dispersal.

Correction to 'The onset of ecological diversification 50 years after colonization of a crater lake by haplochromine cichlid fishes'.

Adaptive radiation research typically relies on the study of evolution in retrospective, leaving the predictive value of the concept hard to evaluate. Several radiations, including the cichlid fishes in the East African Great Lakes, have been studied extensively, yet no study has investigated the onset of the intraspecific processes of niche expansion and differentiation shortly after colonization of an adaptive zone by cichlids. Haplochromine cichlids of one of the two lineages that seeded the Lake Victoria radiation recently arrived in Lake Chala, a lake perfectly suited for within-lake cichlid speciation. Here, we infer the colonization and demographic history, quantify phenotypic, ecological and genomic diversity and diversification, and investigate the selection regime to ask if the population shows signs of diversification resembling the onset of adaptive radiation. We find that since their arrival in the lake, haplochromines have colonized a wide range of depth habitats associated with ecological and morphological expansion and the beginning of phenotypic differentiation and potentially nascent speciation, consistent with the very early onset of an adaptive radiation process. Moreover, we demonstrate evidence of rugged phenotypic fitness surfaces, indicating that current ecological selection may contribute to the phenotypic diversification.

Origin, formation and environmental significance of des-A-arborenes in the sediments of an East African crater lake

Non-hopanoid pentacyclic triterpenoids occur widely in lake sediments, but their biological sources and diagenetic pathways are not fully resolved. We tentatively identified a number of des-A-arborene isomers occurring in relatively high abundance in the 25,000 year (25 kyr) sedimentary record of Lake Chala, a deep crater lake in tropical East Africa. The mono-, di- and tri-unsaturated des-A-arborenes are transformation products of isoarborinol/arborinone. These precursors have an aquatic source and are most likely biosynthesized by algae or aerobic bacteria in the epilimnion. The relatively depleted δ13C values (on average −32.3‰ ± 1.3‰) of des-A-arbor-9(11)-ene are consistent with an aquatic source (algae or aerobic bacteria). In general, isoarborinol and its microbially induced transformation products are found in present and ancient tropical lacustrine settings (typically crater lakes) with permanently anoxic bottom waters and sediments. Based on molecular mechanics calculations of des-A-arborenes, it is clear that these transformation products are not in thermodynamic equilibrium, strongly indicating that their formation is microbially mediated. Subtle temporal and spatial differences in the microbial community might therefore not only dictate the variable relative contributions of different des-A-arborenes found in the sediments of Lake Chala over the last 25 kyr, but also explain the distribution of arborane derivatives in comparable crater-lake settings elsewhere.

Stillbirth in the African Great Lakes region: A pooled analysis of Demographic and Health Surveys.

BackgroundThe aim of this study was to estimate the rate and predisposing factors associated with stillbirth in the African Great Lakes region (Burundi, Congo Democratic Republic, Kenya, Rwanda, Tanzania and Uganda).Methods and findingsCross-sectional data from the most recent Demographic and Health Surveys (DHS) of countries in the African Great Lakes region were used in this study. DHS from Congo Democratic Republic was not included in the analyses because data was not collected for stillbirth in the country survey. A pooled sample of 57046 pregnancies of 7+ months’ duration and 1002 stillbirths were included in the final analysis. The analyses were restricted to stillbirths reported in the 5 years preceding the surveys. Stillbirth was defined as foetal death in the third trimester (≥ 28 weeks’ gestation). Multilevel logistic regression analyses that adjusted for cluster and survey weights were used to determine the factors associated with stillbirth in the Africa Great Lakes region. Health service variables and maternal medical condition variables were not included in the analysis because DHS do not collect data on these variables for pregnancies that did not result in a live birth. Burundi had the highest stillbirth rate per 1000 births [23% (95% CI: 20, 25)] within the region. Factors associated with stillbirth across the region were: no schooling [1.85 (95%Cl: 1.44, 2.38)] and primary education [1.64 (1.32, 2.05)], advanced maternal age [2.39 (95% CI: 1.59, 3.59)], smoking [1.99 (95% CI: 1.19, 3.32)] and drinking water from unimproved sources [1.18 (95% CI: 1.01, 1.37)].ConclusionTo achieve Every Newborn Action Plan (ENAP) stillbirth target of 12 per 1000 births or less by 2030, policy interventions to prevent stillbirth should focus on promoting community-based socio-educational programmes which encourages a healthy lifestyle especially among uneducated women in the advanced age spectrum.

Water level fluctuations and the ecosystem functioning of lakes

Abstract Hydrological regimes are key drivers of productivity and structure in freshwater ecosystems but are increasingly impacted by human activity. Using 17 published food web models of 13 African lakes as a case study, we explored relationships between seasonal and interannual water level fluctuations and 15 attributes related to ecosystem function. We interpreted our results in the context of Odum's ecosystem maturity hypothesis, as systems with higher magnitude fluctuations may be kept at an earlier maturity stage than those that are relatively stable. The data we compiled indicate that long-term changes in the hydrological regimes of African lakes have already taken place. We used Least Absolute Shrinkage and Selection Operator (LASSO) regression to examine relationships between ecosystem attributes and seven physical characteristics. Of these characteristics, interannual water level fluctuation magnitude was the most frequently retained predictor in the regression models. Our results indicate that interannual water level fluctuations are positively correlated with primary and overall production, but negatively correlated with fish diversity, transfer efficiency, and food chain length. These trends are opposite those expected with increasing ecosystem maturity. Interestingly, we found seasonal water level fluctuations to be positively correlated with biomass. An increase in standing biomass is generally associated with more mature ecosystems. However, we found that less production and biomass occurred at high trophic levels in highly fluctuating compared to relatively stable systems. This synthesis provides evidence that water level fluctuations are a key process influencing ecosystem structure and function in lakes.

Biomonitoring of lakes using macroinvertebrates: recommended indices and metrics for use in West Africa and developing countries

Lake systems are under heavy pressure impacting on their biodiversity and associated ecosystem services. This is especially acute in West Africa and developing countries which lack resources and technical capacities for waste disposal, water purification, as well as sufficient scientific capacities for biomonitoring and integrated management. The preservation, monitoring and improvement of lake quality in these countries are, however, of paramount importance. Throughout the developed world, an array of indicators and multimetric indices have been incorporated into lake biomonitoring and assessment. Here, we assess the numerous procedures, metrics and indices using macroinvertebrates as indicators for lake quality and assess applicability in West African lakes and in developing countries more generally. We propose a framework for macroinvertebrate-based monitoring adapted to these countries, including recommendations for developing new indices and adapting tolerance scores of taxa to local conditions. This work underlines the importance of macroinvertebrates for biomonitoring of lake health in West African lakes and developing countries more generally.

Understanding explosive diversification through cichlid fish genomics.

Owing to their taxonomic, phenotypic, ecological and behavioural diversity and propensity for explosive diversification, the assemblages of cichlid fish in the East African Great Lakes Victoria, Malawi and Tanganyika are important role models in evolutionary biology. With the release of five reference genomes and many additional genomic resources, as well as the establishment of functional genomic tools, the cichlid system has fully entered the genomic era. The in-depth genomic exploration of the East African cichlid fauna - in combination with the examination of their ecology, morphology and behaviour - permits novel insights into the way organisms diversify.

The onset of ecological diversification 50 years after colonization of a crater lake by haplochromine cichlid fishes.

Adaptive radiation research typically relies on the study of evolution in retrospective, leaving the predictive value of the concept hard to evaluate. Several radiations, including the cichlid fishes in the East African Great Lakes, have been studied extensively, yet no study has investigated the onset of the intraspecific processes of niche expansion and differentiation shortly after colonization of an adaptive zone by cichlids. Haplochromine cichlids of one of the two lineages that seeded the Lake Victoria radiation recently arrived in Lake Chala, a lake perfectly suited for within-lake cichlid speciation. Here, we infer the colonization and demographic history, quantify phenotypic, ecological and genomic diversity and diversification, and investigate the selection regime to ask if the population shows signs of diversification resembling the onset of adaptive radiation. We find that since their arrival in the lake, haplochromines have colonized a wide range of depth habitats associated with ecological and morphological expansion and the beginning of phenotypic differentiation and potentially nascent speciation, consistent with the very early onset of an adaptive radiation process. Moreover, we demonstrate evidence of rugged phenotypic fitness surfaces, indicating that current ecological selection may contribute to the phenotypic diversification.

Environmental Surveillance of Vibrio cholerae O1/O139 in the Five African Great Lakes and Other Major Surface Water Sources in Uganda.

Cholera is a major public health problem in the African Great Lakes basin. Two hypotheses might explain this observation, namely the lakes are reservoirs of toxigenic Vibrio cholerae O1 and O139 bacteria, or cholera outbreaks are a result of repeated pathogen introduction from the neighboring communities/countries but the lakes facilitate the introductions. A prospective study was conducted in Uganda between February 2015 and January 2016 in which 28 selected surface water sources were tested for the presence of V. cholerae species using cholera rapid test and multiplex polymerase chain reaction. Of 322 water samples tested, 35 (10.8%) were positive for V. cholerae non O1/non O139 and two samples tested positive for non-toxigenic atypical V. cholerae O139. None of the samples tested had toxigenic V. cholerae O1 or O139 that are responsible for cholera epidemics. The Lake Albert region registered the highest number of positive tests for V. cholerae non O1/non O139 at 47% (9/19). The peak period for V. cholerae non O1/non O139 positive tests was in March–July 2015 which coincided with the first rainy season in Uganda. This study showed that the surface water sources, including the African Great Lakes in Uganda, are less likely to be reservoirs for the observed V. cholerae O1 or O139 epidemics, though they are natural habitats for V. cholerae non O1/non O139 and atypical non-toxigenic V. cholerae O139. Further studies by WGS tests of non-toxigenic atypical V. cholerae O139 and physicochemical tests of surface water sources that supports V. cholerae should be done to provide more information. Since V. cholerae non O1/non O139 may cause other human infections, their continued surveillance is needed to understand their potential pathogenicity.

Gene flow and genetic structure in Nile perch, Lates niloticus, from African freshwater rivers and lakes.

BackgroundGeological evolution of the African continent has been subject to complex processes including uplift, volcanism, desert formation and tectonic rifting. This complex geology has created substantial biogeographical barriers, and coupled with anthropogenic introductions of freshwater fishes, has influenced the genetic diversity, connectivity and sub-structuring of the teleost fauna. Nile perch, Lates niloticus, is an iconic fish in Africa and is of high commercial importance, both in the species’ native range and where it has been translocated. However, the species is in decline and there is a need to understand its population genetic structure to facilitate sustainable management of the fishery and aquaculture development.MethodologyNile perch tissue samples were acquired from two West and four East (Lakes; Albert, Kyoga, Victoria and Turkana) African locations. Nineteen polymorphic microsatellite loci were used to study the genetic variation among populations across regions (West and East Africa), as well as between native and introduced environments within East Africa.Principal findings and their significanceResults revealed strong and significant genetic structuring among populations across the sampled distribution (divergence across regions, FCT = 0.26, P = 0.000). STRUCTURE analysis at a broad scale revealed K = 2 clusters, the West African individuals were assigned to one cluster, while all individuals from the East African region, regardless of whether native or introduced, were assigned to another cluster. The distinct genetic clusters identified in the current study between the West and East African Nile perch, appear to have been maintained by presence of biogeographic barriers and restricted gene flow between the two regions. Therefore, any translocations of Nile perch should be carefully considered across the regions of West and East Africa. Further analysis at a regional scale revealed further structuring of up to K = 3 genetic clusters in East African Nile perch. Significantly (P < 0.05) lower genetic diversity based on analysis of allelic richness (AR) was obtained for the two translocated populations of Lake Kyoga (AR = 3.61) and Lake Victoria (AR = 3.52), compared to Nile perch populations from their putative origins of Lakes Albert (AR = 4.12) and Turkana (AR = 4.43). The lower genetic diversity in the translocated populations may be an indication of previous bottlenecks and may also indicate a difficulty for these populations to persist and adapt to climatic changes and anthropogenic pressures that are currently present in the East African region.

Breaking the Conflict Cycle, Building Peaceful Communities: Participatory Photography and Storytelling With African Diasporas in Sydney

Even after resettling in a new country, the trauma and resentment caused by the conflict experienced in their homeland are passed on from generation to generation among diaspora communities. One of the factors that perpetuate the conflict in their new reality is the ethnic separation that continues to be upheld and reinforced, from parents to children. This article discusses the experience of a participatory photography project that brought together young people from the Congolese, Rwandan, Burundian, and Ugandan communities living in Sydney (Australia), whose lives are still impacted by the legacy of the conflicts that have been ravaging the African Great Lakes region. This initiative, which wanted to provide a space to encourage communication between different groups and enable the promotion of peace between communities starting from the youth, is analyzed here, and reflections are offered on the use of this method with diaspora groups.