First assessment of age and sex structures of elephants by using dung size analysis in a West African savannah

1. An age and sex structure study of the West African savannah elephant (Loxodonta africana africana) population of the Nazinga Game ranch (Burkina Faso) was carried out using direct sightings of individuals near water points, where they group during hot periods of the day, and droppings circumference measurements of dung pile along line transects, during the dry seasons of 2007 and 2008. The age structure, from direct observation data, was estimated by classifying the individuals into 9 age-class-categories based on body size and eruption (length) of tusks.2. The frequency distribution of number of individuals into the age-class-categories showed high similarity with the distribution of circumference measurements of dung-piles that the individuals were seen depositing. Fifty dung-piles measured soon after they were deposited (Class A) and after they dried (to class C) showed a significant difference between the circumference measurements in relation to the time elapsed between the measurements.3. The frequency distribution of dung circumference classes of the observed elephants was similar to that of the dung-piles measured along the transects in 2008. Therefore, dung-piles measurements were used to estimate the Nazinga Game Ranch savanna elephant population’s age and sex structures at the end of dry seasons of 2007 and 2008. We advocated that the Nazinga elephant population consisted mainly of sub-adults.4. The sex ratio was estimated to be in favour of females (1/2). The age-class-specific sex ratio was uneven for calves and young individuals, while being in favour of females with adults. Individuals of less than 1 year represented 6% of the population during the study period

Variation de la composition des communautés de reptiles dans divers types de plantations dans le Sud-Est du Nigéria

Despite many studies of reptile community composition in Africa, no studies document the variation of reptile assemblages across different plantation types. Here, we document the community composition (richness, taxonomic composition, dominance, evenness) in relation to seasonality in eight different plantation types (from cassava-yam to banana-plantain, and from cacao to mixed orchards), and at three distinct study areas in the River Niger Delta of southern Nigeria. Our study showed that the community composition of reptiles did not differ significantly across plantation types in terms of species diversity and richness during the wet season, but it did so during the dry season (possibly as a consequence of survey effects). A few highly dominant lizard species (Agama agama and Trachylepis affinis) constituted the great majority of the specimens encountered during field work. Some snake species, although usually not very abundant (in terms of relative number) were observed in nearly all sites. Typical forest specialists may enter plantations, but they were never abundant there. Tortoises did not occur in any plantations. Diversity indices and multivariate sets of analyses revealed minor differences among study areas and across plantation types in terms of community composition patterns. However, some types of monoculture plantations had higher dominance and lower evenness values than mixed orchards (= poly-culture farms), showing that monocultures provided least quality habitats for reptile communities than poly-culture farms, favoring few species due to the relatively homogeneous niche availability. Overall, a clear process of biotic homogenization, with increases in dominance, was clearly observed at all sitesEn dépit de leur nombre élevé aucune des études de la composition des communautés de reptiles africains ne renseigne de manière comparative sur les peuplements de reptiles dans divers types de plantations. Nous présentons ici la composition (richesse, composition taxinomique, dominance, équitabilité) de ces communautés en fonction de la saison dans huit types de plantations (de manioc-yam à banane plantain et de la cacaoyère aux vergers mixtes) et trois zones d’étude distinctes dans le delta du Niger dans le sud du Nigéria. Notre étude a montré que la composition des peuplements de reptiles ne diffèrerait pas de manière significative selon le type de plantation en termes de richesse et de diversité spécifiques durant la saison des pluies mais le ferait en saison sèche (peut-être une conséquence des effets de l’échantillonnage). Un petit nombre d’espèces dominantes de lézards (Agama agama et Trachylepis affinis) ont fourni la grande majorité des spécimens rencontrés durant la période d’étude. Quelques espèces de serpents, quoique en général pas très abondantes (en termes d’abondances relatives), furent observées dans presque tous les sites. Des espèces typiquement forestières peuvent se montrer dans les plantations mais sans jamais y être abondantes. Des tortues n’ont été trouvées dans aucune plantation. Des indices de diversité et des analyses multivariées n’ont révélé que de petites différences entre les zones d’étude et entre les types de plantations en termes de patrons de composition du peuplement. Toutefois, quelques types de monocultures présentaient une plus grande dominance et une plus faible équitabilité que les vergers mixtes (polycultures), suggérant que les monocultures offriraient aux reptiles des habitats de moindre qualité que les polycultures, favorisant moins d’espèces en raison d’une disponibilité de niches relativement homogène. D’une manière générale un processus d’homogénéisation biotique, avec des accroissements de dominance, a été clairement observé sur tous les site

refugee camps as an opportunity for promoting alternative development strategies based on carbon credits

Abstract The difficult social issues faced by non-governmental organizations regarding planning, management, and evolution of the refugee camps led to evaluating alternative development strategies. Indeed, innovative technologies could be promoted for sustainably enhancing local economy. The present model suggests the exploitation of high-albedo materials to generate cool oases in hot climate contexts. The benefits derived by this proposal were investigated by simulating the application of high-albedo devices on shelters in Zaatari, then the avoided carbon emissions were quantified, and several scenarios were discussed. In the framework of the Emissions Trading System, the carbon credits, which can be obtained and sold by contributing to the global warming mitigation process, are estimated to be around 150,000 tons CO 2-eq . Considering the market tendencies presented during the COP21 in Paris, the intervention is demonstrated to be sustainable in economic and environmental terms. The payback period is estimated in 3 years in the most reliable scenario. The work presents the main results of a wider research that also included consideration about the urban planning of the camps

Trophic resource use by sympatric vs. allopatric Pelomedusid turtles in West African forest waterbodies

Organisms that are similar in size, morphological characteristics, and adaptations, including vertebrates, often coexist by partitioning the available resources (food, space, and time). So, studies of the dynamics of these cases of coexistence are scientifically interesting. Here, we study a coexistence case of two species of freshwater turtles inhabiting the forest waterbodies of West Africa, focusing on the dietary habits of the two species. We found that both turtle species are omnivorous generalists, eating both vegetal and animal matter abundantly. However, there were clear interspecific differences, with the larger of the two species (P. cupulatta) eating more vertebrates (mainly fish but occasionally other vertebrates), whereas P. castaneus consumed more invertebrates. These patterns appeared consistently within the species and across sites, highlighting that the same patterns were likely in other conspecific populations from the Upper Guinean forest streams (Côte d’Ivoire and Liberia). Our study also showed that interspecific competition for food does not occur between these two species; instead, previous studies uncovered that a clear partitioning of the habitat niche occurs. We conclude that the food resource is likely unlimited in the study areas, as it is not the case in more arid environments (since food shortages may occur during the dry season). We anticipate that, within the Pelomedusidae communities throughout Africa, intense competition for food probably occurs in the Sahel and Sudanian vegetation zones, particularly during the dry months, but is unlikely within the Guinea and wet savannah region and even less likely in the Guineo-Congolian rainforest region

Exploring the main threats to the threatened African spurred tortoise Centrochelys sulcata in the West African Sahel

AbstractThe African spurred tortoiseCentrochelys sulcatais the second largest terrestrial turtle, with a scattered distribution across the West African Sahel. This species is threatened and declining consistently throughout its range, but little is known about the causes of its decline. It has been hypothesized that the decline is attributable to (1) competition with domestic cattle, (2) wildfire, and (3) the international pet trade. We conducted a series of analyses to investigate these three causes. Hypotheses 1 and 2 were analysed using a spatially explicit approach, using a database of the Food and Agriculture Organization of the United Nations and logistic regression modelling; hypothesis 3 was tested by analysing the CITES trade database for 1990–2010. We found a significant negative correlation between intensity of grazing (expressed as density of cattle, km−2) and the presence of spurred tortoises, and this negative effect increased when coupled with high fire intensity, whereas wildfires alone did not have a significant influence on the species' distribution at the global scale. There was a decrease in the annual export of wild individuals for the pet trade after the introduction of export quotas by country and by year, but trade data must be considered with caution

α-Synuclein Aggregates with β-Amyloid or Tau in Human Red Blood Cells: Correlation with Antioxidant Capability and Physical Exercise in Human Healthy Subjects

Neurodegenerative disorders (NDs) are characterized by abnormal accumulation/misfolding of specific proteins, primarily α-synuclein (α-syn), β-amyloid1–42 (Aβ), and tau, in both brain and peripheral tissue. In addition to homo-oligomers, the role of α-syn interactions with Aβ or tau has gradually emerged. The altered protein accumulation has been related to both oxidative stress and physical activity; nevertheless, no correlation among the presence of peripheral α-syn hetero-aggregates, antioxidant capacity, and physical exercise has been discovered as of yet. Herein, the content of α-syn, Aβ, tau, and of their heterocomplexes was determined in red blood cells (RBCs) of healthy subjects (sedentary and athletes). Such parameters were related to the extent of the antioxidant capability (AOC), a key marker of oxidative stress in aging-related pathologies, and to physical exercise, which is known to play an important preventive role in NDs and to modulate oxidative stress. Tau content and plasma AOC toward hydroxyl radicals were both reduced in older or sedentary subjects; in contrast, α-syn and Aβ accumulated in elderly subjects and showed an inverse correlation with both hydroxyl AOC and the level of physical activity. For the first time, α-syn heterocomplexes with Aβ or tau were quantified and demonstrated to be inversely related to hydroxyl AOC. Furthermore, α-syn/Aβ aggregates were significantly reduced in athletes and inversely correlated with physical activity level, independent of age. The positive correlation between antioxidant capability/physical activity and reduced protein accumulation was confirmed by these data and suggested that peripheral α-syn heterocomplexes may represent new indicators of ND-related protein misfolding

La viande de brousse : des enquêtes révèlent des points de controverse sur la dynamique de son commerce au Nigéria

Sur la base d’enquêtes dans le sud du Nigéria, cet article examine (i) si la viande de brousse est toujours une source cruciale de protéines pour les communautés locales, (ii) si elle est toujours culturellement bien justifiée et (iii) si, selon les préférences des consommateurs, des valeurs différentes sont attribuées aux divers types d’espèces constituant cette viande de brousse. De plus, cet article fournit des informations sur la question de savoir (iv) si le commerce de la viande de brousse épuise localement les populations des espèces ciblées, et (v) si la disparition sur les marchés de grands animaux est signe de leur extermination locale. Une combinaison d’entretiens avec des hommes et des femmes de différentes classes d’âge, incluant des chasseurs, consommateurs et vendeurs, a été conduite dans divers localités nigérianes correspondant à différentes conditions d’habitat et de caractéristiques socio-économiques et ethniques. Les résultats suggèrent que la consommation de viande de brousse, en particulier dans les zones urbaines, n’a pas une grande valeur de subsistance, sauf pour une petite sous-section de la communauté. De fait, même dans les zones rurales, moins de 30 % des personnes de moins de 50 ans interrogées ont répondu consommer fréquemment de la viande de brousse. L’importance culturelle de la viande de brousse a substantiellement diminué dans les années récentes, comme en témoigne le fait que (i) cette source de nourriture a été rapidement abandonnée durant la crise d’Ebola en 2014 et (ii) la plupart des personnes interrogées ont affirmé n’en manger que rarement voire pas du tout. Les données recueillies vont dans le sens de ce que le prix d’une carcasse serait principalement déterminé par la taille de l’animal et non pas par la préférence des consommateurs. L’utilisation et le commerce de la viande de brousse peuvent certainement épuiser localement les populations des espèces animales ciblées. Néanmoins, il n’y a toujours pas suffisamment de preuves empiriques de la notion selon laquelle quand les grands animaux disparaissent des marchés cela signifierait que leurs populations auraient été considérablement épuisées voire exterminées. De fait, sur la base d’éléments culturels exposés par les chasseurs interrogés, il semblerait que cette notion soit erronée, du moins en ce qui concerne les régions ouest-africaines les plus riches et les plus économiquement dynamiques. Il est conseillé à ceux qui étudient la viande de brousse d’explorer plus en profondeur la flexibilité culturelle des communautés humaines avant de généraliser des conclusions, évitant ainsi d’extrapoler à grande échelle des conclusions insuffisamment fondées car basées sur des données collectées à très petite échelle spatiale et durant de courtes périodes de temps.Using questionnaire surveys in southern Nigeria, this paper explores whether: (i) bushmeat is still a crucial source of animal protein for local communities; (ii) is still culturally very relevant; and (iii) if people value differently the various kinds of bushmeat species because of customer preferences. In addition, this paper provides information on whether (iv) the bushmeat trade locally depletes target game species; and (v) whether the disappearance of large animals from the markets would indicate their local extirpation from the wild. A combination of interviews was carried out with both men and women of different age classes including hunters, consumers and sellers, from different Nigerian locations with different habitat conditions, socio-economic and ethnic characteristics. Results of these interviews suggest that the consumption of bushmeat has little subsistence value, especially in urban areas, except for a small sub-section of the community. Indeed, even in rural areas less than 30 % of the interviewees of less than 50 years age answered that they frequently eat bushmeat. Cultural importance of bushmeat decreased substantially in recent years, as shown by that (i) this food source was quickly abandoned by people during the 2014 Ebola crisis, and (ii) most of questionnaire respondents affirmed that they would have eaten bushmeat only rarely or even not at all. There was support for the notion that the price of a carcass was mainly determined by the animal size and not by the consumer preference. Bushmeat utilization and trade may certainly deplete target animal species at the local scale. Nonetheless, there is still no sufficient empirical evidence for the notion that, when large animals disappeared from the markets, it meant that their populations were heavily depleted or even extinct. Indeed, based on cultural elements highlighted by interviewed hunters, there is evidence that this notion may be wrong, at least in the richest and economically more dynamic regions of West Africa. It is advised that bushmeat studies should explore more in depth the cultural flexibility of human communities before drawing generalized conclusions, thus avoiding unsupported large-scale conclusions based on data collected at a very small spatial scale and during short time periods

Impact of COVID-19 on wild meat trade in Nigerian markets

Wild meat plays a crucial role in the food security and cash income of subsistence hunters in the tropics and subtropics in Africa, South America, and SE Asia (Coad et al., 2019; Fa et al., 2022). This meat is regularly traded in markets in many towns and cities (see Fa et al., 2019). In Nigeria, the amount of meat sold from most species crashed dramatically after the Ebola virus outbreak in 2014, highlighting the awareness of the general public of a link between disease risk and wild meat (Akani et al., 2015; Funk et al., 2021). The opportunities for zoonotic spill-over have increased in parallel with the increase of the intensity and extent of bushmeat trade over the last decades (Karesh & Noble, 2009). The report by UNEP, International Livestock Research Institute (2020) on preventing the next pandemic lists increasing human demand for animal protein among seven human-mediated factors as the most likely driving the emergence of zoonotic diseases, which includes wild meat hunting

Nesting trees used by a pest bird (Village Weaver, Ploceus cucullatus): a large field survey suggests further human conflicts with local stakeholders in Southern Nigeria

The village weaver (Ploceus cucullatus) is a common colonial nesting bird widespread throughout Sub-Saharan Africa. It is known to weave its nests from leaf strips from a variety of tree species (mainly coconuts trees, oil palm trees) associated with human settlement areas, grasses, and other available plants. In this regard, this bird was considered a pest for its impact on different economic activities. Although extensive literature is already available on the parasitic role of village weavers, there is still a lack of analytical data that outlines which tree species are used for nesting and in what proportion, as well as the related implications in terms of economic impacts. Here, we carried out the first comprehensive arrangement of trees used by this species for nesting in Southern Nigeria (West Africa), checking for possible different impacts on stakeholders. In April 2021, we searched for village weaver nesting in 95 sites in 77 communities from 24 local government areas in Southern Nigeria, during 14 field surveys. Within each site, we collected GPS coordinates and counted the number of active nests, nesting birds and occupied trees. We recorded a total of 5,776 nests and 2,140 birds in 94 plants belonging to 23 tree species selected for nesting. Oil palm (Elaeis guineensis; n = 45) was the most used tree species, as 2,990 (51.77%) nests and 873 (40.79%) birds were recorded. Our results indicate the preference for nesting on trees used by stakeholders belonging to agricultural (palm farmers), touristic (operators) and energy (gas flare stations) sectors with economic implications about the conflict with this pest species

Spatial Niche Expansion at Multiple Habitat Scales of a Tropical Freshwater Turtle in the Absence of a Potential Competitor

Resource partitioning, the division of limited resources by species to help avoid competition, has been observed in freshwater turtle assemblages in several natural systems but has rarely been studied in tropical African ecosystems. Here, we investigate habitat preferences of two congeneric species in the family Pelomedusidae, Pelusios castaneus and P. cupulatta, in riverine/wetland habitats in the southern Ivory Coast (West Africa). Pelusios castaneus is a widespread species across West-central African savannahs and open forests, whereas P. cupulatta is endemic to the Upper Guinean forest region in West Africa. The two species have a similar diet composition (mainly carnivorous) but diverge considerably in body size, P. cupulatta being much larger. We use hand-fishing-nets and fishing funnel traps to record turtles in 18 distinct sites and analyze habitat preferences by species at two spatial scales. At a macro-habitat scale, P. castaneus is captured mainly in marshlands, whereas P. cupulatta is found in both rivers and wetlands. The two species differ significantly in their use of: (i) banks (P. castaneus being found primarily in spots with grassy banks, whereas P. cupulatta is found in spots with forested banks), and (ii) aquatic vegetation (P. cupulatta prefers spots with more abundant aquatic vegetation than P. castaneus), but both species select sites with no or moderate current. Additionally, in sites where P. cupulatta is not found, P. castaneus expands its spatial niche at multiple habitat scales, notably invading waterbodies with forested banks. Our results suggest that these two Pelomedusid turtle species potentially compete in the freshwater habitats in the southern Ivory Coast