African Journal of Ecology最新文献

{"title":"‘How the (Elephant) Cow Ate the Cabbage’: Cussonia spicata in the Presence of Elephants in the Subtropical Thicket Biome, South Africa","authors":"Chanté van der Merwe,&nbsp;Ashley-Kate Davidson,&nbsp;Dan Parker,&nbsp;Nokubonga Mgqatsa","doi":"10.1111/aje.70047","DOIUrl":"https://doi.org/10.1111/aje.70047","url":null,"abstract":"<div>\u0000 \u0000 <p>Using transect surveys, we examined the effects of African savannah elephant (<i>Loxodonta africana</i>) herbivory on cabbage trees (<i>Cussonia spicata</i>) within South Africa's Subtropical Thicket Biome over 15 years (2008–2023). There was an 80% reduction in tree density, from 14.3 to 1.4 trees per 0.1 km², and a significant decrease in average height. Notably, as cabbage tree numbers declined, elephant browsing intensity also decreased. Trees in steeper areas survived better, suggesting these act as natural refuges. Our findings highlight the critical need for targeted conservation strategies and long-term ecosystem monitoring to preserve these keystone species in enclosed reserves.</p>\u0000 </div>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Resolution GPS Tracking Data Reveal Inter-Individual and Seasonal Variations in Habitat Selection Strategies by the Critically Endangered African White-Backed Vulture Gyps africanus in the Hwange Ecosystem of Zimbabwe","authors":"Mark Zvidzai,&nbsp;Mhosisi Masocha,&nbsp;Peter Mundy,&nbsp;Fadzai M. Zengeya,&nbsp;Henry Ndaimani,&nbsp;Amon Murwira","doi":"10.1111/aje.70044","DOIUrl":"https://doi.org/10.1111/aje.70044","url":null,"abstract":"<div>\u0000 \u0000 <p>Effective conservation of critically endangered species should be guided by empirical evidence on how they interact with the environment at multiple scales. Yet, such information is lacking for many endangered species such as African White-backed Vultures (AWbV) <i>Gyps africanus</i>. Habitat selection modelling is a promising tool for inferring habitat selection strategies by species to guide conservation planning. This study investigated how habitat selection patterns for AWbV differ in respect of intrinsic individual traits and seasonality. To achieve this goal, six AWbV were captured and attached with solar-powered Global Positioning Systems (GPS) tracking devices. GPS data were then integrated with biologically relevant environmental predictors. Two modelling frameworks, namely binary logistic regression and Ecological Niche Factor Analysis, were fitted to develop habitat selection models at three scales based on pooled, individual and seasonal data. Results indicate that the six AWbV reflect specialist tendencies, with a narrow ecological niche. Further, results reveal a significant positive relationship between predicted presence of the six AWbV and the human footprint index while a consistent negative relationship with mammalian density index was also uncovered. Complex but significant relationships were also uncovered between AWbV and other variables such as the Normalised Difference Vegetation Index, mean daily temperature and thermal uplift. Results from the study suggest that AWbV response strategies to environmental heterogeneity are individual and season-specific. This therefore calls for researchers to disaggregate movement ecology data to multiple scales as this may improve the utility of habitat selection modelling to inform biodiversity conservation planning.</p>\u0000 </div>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacterial Communities in the East African Coastal Waters of the Indian Ocean","authors":"Ola A. Olapade","doi":"10.1111/aje.70046","DOIUrl":"https://doi.org/10.1111/aje.70046","url":null,"abstract":"<p>Presently, very sparse information exists about the occurrences and diversity of microbes in the western Indian Ocean (WIO) relative to other areas of the ocean. In this study, high-throughput sequencing of 16S rRNA genes and metagenomic approaches were utilised to examine microbial assemblages in Kenya and Tanzania. Results from 24 locations showed that <i>Proteobacterial</i> members made up the majority of the bacterial assemblages. Other dominant phyla were <i>Bacteroidetes</i> (9%–10%), <i>Firmicutes</i> (1.4%–8%), <i>Actinobacteria</i> (4%–6%) and <i>Acidobacter</i> (3.4%–3.6%). Combinations of diversity (alpha and beta) as well as Pearson correlation analyses showed that assemblages in Kenya clustered together and differed from those in Tanzania because of covariation with various environmental factors, such as temperature and salinity.</p>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/aje.70046","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scaling the Slopes: A Biodiversity Assessment of the Communities of Epigeous Insects Across Mont Nimba's Altitudinal Gradient in Western Côte d'Ivoire","authors":"Sié Dah,&nbsp;Mamadou Koné,&nbsp;Kanvaly Dosso,&nbsp;Seydou D. Soro,&nbsp;Seydou Tiho,&nbsp;Souleymane Konaté","doi":"10.1111/aje.70042","DOIUrl":"https://doi.org/10.1111/aje.70042","url":null,"abstract":"<div>\u0000 \u0000 <p>This study was initiated to investigate the abundance and taxonomic diversity of entomofauna at three levels: 400–500, 800–900 and 1400–1500 m above sea level along the altitudinal gradient of Mount Nimba. The insect inventories were carried out using pitfall traps and coloured traps along an altitudinal gradient in the main vegetation facies. As a result, a total of 2828 individuals were found, which were distributed in eight orders and 86 families. Coleoptera was the most abundant group with 30 families, followed by Diptera (23 families) and Hymenoptera (18 families). The secondary forest (between 400 and 500 m) appears to be the most populated and richest habitat, with 980 insects collected from 53 families. Conversely, the grassy savannah at high altitude meadows (Richard Molard site located between 1400 and 1500 m) is the least populated (39 insects collected) and the least rich (12 families). This pioneering study in the Mont Nimba Integral Nature Reserve provided a general overview of the Reserve's epigeic entomofauna.</p>\u0000 </div>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Modelling of the Temporal Patterns and Intensity of Wire Snare Poaching and Predicting Land Cover Change Dynamics in a Semi-Arid Protected Area","authors":"Nobert Tafadzwa Mukomberanwa,&nbsp;Patmore Ngorima,&nbsp;Thomas Musora","doi":"10.1111/aje.70040","DOIUrl":"https://doi.org/10.1111/aje.70040","url":null,"abstract":"<div>\u0000 \u0000 <p>The spatial and temporal dynamics of poaching, along with continuous land cover alterations like deforestation and agricultural expansion, hinder efficient wildlife management. Changes in land cover could either generate new poaching opportunities or impede access to previously exploited areas. With the doubling of Africa's human population, protein resources will be strained, boosting the purchase and harvest of bushmeat for sustenance and income. In regions where meat poaching transpires, wire snaring is a prevalent technique due to its affordability, efficacy, and ease of acquisition, installation, and concealment. Due to their non-selective nature, snares can inflict severe by-catch mortality on a range of species. Yet, the necessity of projecting future values of a time series traverses across a range of fields. Powerful methods have been developed to capture these components by defining and estimating statistical models. Policymakers must plan several months or years ahead, since drawing up policies and actual policy implementation may take several months or years. The aims of this study were to (i) estimate the spatiotemporal patterns and intensity of wire snare poaching and (ii) predict future land cover dynamics using land change models and assess how these changes may influence poaching risk in the coming years. The Autoregressive Integrated Moving Average (ARIMA) was utilised for time series analysis and forecasting. Kernel density estimator (KDE) was used to smooth point data (in this case the locations of wire snares) to create a continuous surface that shows areas of high and low density. The analysis of land use and land cover takes into account the utilisation of Landsat satellite image products. Satellite images for the years 2020, 2022, and 2024 were utilised as inputs for forecasting future land cover scenarios using cellular automata artificial neural network (CA-ANN). The results from the ARIMA show an increase in the wire snares which would enhance the possibility for human–wildlife conflicts by the year 2028. Kernel density estimators pinpoint regions where wire snares are most concentrated; conservation teams can focus their patrols, thus helping to conserve species more efficiently. CA-ANN reveals marginal changes in land use and land cover which might enhance the likelihood for human–wildlife conflicts. Time series forecasting helps estimate when and where poaching activity is likely to spike. By identifying monthly trends, conservation teams can take preventative efforts rather than reacting after poaching has occurred.</p>\u0000 </div>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Giant Gardeners of the Forest: How African Forest Elephants (Loxodonta cyclotis) Shape Mammal Biodiversity in the Republic of Congo","authors":"Laura Versavaud,&nbsp;Nina Giotto,&nbsp;Paul Aczel,&nbsp;Gabriel Michelin,&nbsp;Jean-François Gerard","doi":"10.1111/aje.70043","DOIUrl":"https://doi.org/10.1111/aje.70043","url":null,"abstract":"<p>The African forest elephant (<i>Loxodonta cyclotis</i>), a critically endangered species, is a megaherbivore that browses and transforms large quantities and varieties of vegetation during its foraging activities and movements. However, the cascading effects of this ‘ecosystem engineer’ on animal biodiversity are poorly known. In this study, based on data from 38 camera traps placed in a lowland forest in the National Park of Conkouati-Douli, Republic of Congo, we examined the effects of the forest elephant and ecological variables like flooding time on local biodiversity in mammal species. Camera traps recorded 31 terrestrial mammalian species and our results show that mammal biodiversity was maximum for intermediate levels of frequentation by forest elephants. The occurrence frequency of various mammal species also reached its highest value under similar conditions. Possible explanations for this phenomenon are discussed.</p>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/aje.70043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Ecology and Home Range Drivers of the Weyns's Duiker (Cephalophus weynsi) in Rainforest Habitat","authors":"Daov Naom Beguide Bobo,&nbsp;Mattia Bessone,&nbsp;Roland Cleva,&nbsp;Barbara Fruth","doi":"10.1111/aje.70041","DOIUrl":"https://doi.org/10.1111/aje.70041","url":null,"abstract":"<p>In Central Africa's tropical forests, duikers (<i>Cephalophus</i> spp.) are essential seed dispersers and prey for apex predators and humans. However, little is known about their spatial ecology, with no studies available for medium-sized species south of the Congo River. Here, we study forest duiker spatial use in the buffer zone of Salonga National Park, Democratic Republic of the Congo. We assess capture success of (1) collective day capture with nets and (2) collective night capture with head-torches and use GPS/VHF collars to investigate species-specific home-range (a) size, (b) use and (c) overlap. Across 7 months, 47 capture attempts allowed collaring 13 Weyns's (<i>C. weynsi</i>), two bay (<i>C. dorsalis</i>), and one black-fronted (<i>C. nigrifrons</i>) duiker, with similar success between techniques. Weyns's duikers mean home range size was 29.38 ha, with stable core areas and dynamic boundaries. While one breeding pair showed 72.80% overlap and a mean interindividual distance of 288 m, overlap in non-breeding pairs ranged between 4.5% and 52.2%, with an average interindividual distance of 533 m. Our assessment of the spatial use of Weyns's duikers suggests that anthropogenic disturbances might affect spatial behaviour and reproductive success. Further research on the spatial ecology of forest ungulates is key to improving conservation strategies.</p>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/aje.70041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wire Warriors: Protecting South Africa's Savannah Trees From Elephant Encounters","authors":"Jitske S. Elzinga,&nbsp;Michelle Henley,&nbsp;Robin Cook,&nbsp;Willem Frederik de Boer","doi":"10.1111/aje.70038","DOIUrl":"https://doi.org/10.1111/aje.70038","url":null,"abstract":"<p>In the Associated Private Nature Reserves (APNR), part of the Greater Kruger National Park, large tree densities decline due to the impact of browsing elephants (<i>Loxodonta africana</i>). Wire netting around the trunk of knobthorn (<i>Senegalia nigrescens</i>) and marula (<i>Sclerocarya birrea</i>) trees is used to protect individual trees. The success of the wire netting will depend on the species, the size of the tree, and variables that describe the tree's location in terms of its suitability for elephants. The objective of this study was therefore to quantify the impact of wire netting on tree survival, and to test whether tree, elephant and landscape variables were associated with tree survival. Data were collected from a nine-year survey of elephant impacts on tree species by Elephants Alive. Elephants Alive is a non-profit organisation whose mission is to ensure the survival of Africa's elephants through protection and research. A Cox proportional hazards model, that is, a survival analysis, was fitted for tree mortality and elephant impact over time. Wire netting significantly increased tree survival (<i>p</i> &lt; 0.001), particularly for trees with a large diameter at breast height (DBH: 39–106 cm), and had a greater protective effect on large marula trees compared to knobthorn trees (<i>p</i> = 0.045). Landscape factors also influenced tree survival, with trees closer to the Kruger National Park (<i>p</i> &lt; 0.001), at lower elevations (<i>p</i> = 0.001), and within 500–1500 m of water points (<i>p</i> = 0.074) having a higher risk of mortality. Trees further from roads (251–335 m) had higher survival (<i>p</i> = 0.073). These results suggest that wire netting is an effective mitigation tool for large trees in elephant-impacted landscapes, but its implementation should consider site-specific environmental factors and elephant movement patterns.</p>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 3","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/aje.70038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How Natural Enemies Shape Gall Wasp Diversity in Oak Cynipid Communities","authors":"Rachid Kechrid,&nbsp;Yasmine Adjami,&nbsp;Khamssa Kermiche,&nbsp;Mohamed Laid Ouakid","doi":"10.1111/aje.70037","DOIUrl":"https://doi.org/10.1111/aje.70037","url":null,"abstract":"<div>\u0000 \u0000 <p>The action of natural enemies within a model tri-trophic system, such as oak cynipid communities, can provide valuable insight into the mechanisms underlying the variation in gall inducer diversity across geographic gradients. Two hypotheses were formulated: (1) The diversity and abundance patterns of cynipid gall wasps, their parasitoids and inquilines differ between high- and low-altitude habitats. (2) Parasitoids and inquilines are involved in mechanisms that influence the abundance patterns of gall wasps. In order to test these hypotheses, we established a study site at various altitudes in the northeastern region of Algeria, selecting three localities: Bouzizi, Ghora and Mechrouha. In each of these localities, two distinct habitats were identified: one located at a lower altitude and the other at a higher altitude. Bud and acorn galls on <i>Quercus faginea</i> were collected, and the insects that emerged from these galls were then identified. The study showed that gall wasps had markedly greater abundance, species richness and diversity in low-altitude habitats. In contrast, parasitoids showed significantly higher abundance, species richness and diversity in high-altitude habitats. Conversely, there is no significant difference in the abundance and diversity of inquiline species between high and low altitudes. The rates of parasitism and inquilinism escalated at elevated elevations but diminished at lower altitudes. A negative correlation was seen between the parasitism rate and the gall wasp population (<i>r</i> = 0.87, <i>r</i>² = 0.77, <i>p</i> &lt; 0.001), as well as between the inquilinism rate and the gall wasp populations (<i>r</i> = 0.86, <i>r</i>² = 0.75, <i>p</i> &lt; 0.001). The results presented in this study confirm the involvement of parasitoids and inquilines in the mechanisms that influence the abundance patterns of gall wasps through their varying pressures between high- and low-elevation habitats.</p>\u0000 </div>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 2","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Minimal Soil Impacts of Caesalpinia decapetala Invasion in South Africa's Vhembe Biosphere Reserve","authors":"Luambo Jeffrey Ramarumo,&nbsp;Gladman Thondhlana,&nbsp;Sheunesu Ruwanza","doi":"10.1111/aje.70036","DOIUrl":"https://doi.org/10.1111/aje.70036","url":null,"abstract":"<p>We assessed the effects of <i>Caesalpinia decapetala</i> (Roth) Alston invasion on soil physical properties over 3 summer months in Vhembe Biosphere Reserve, South Africa. Topsoils were collected beneath replicated invaded and uninvaded conditions and assessed for soil moisture, water repellency, penetration resistance, infiltration and hydraulic conductivity. Results showed no significant (<i>p</i> &gt; 0.05) differences between invasion conditions for soil penetration resistance levels and infiltration rates, but monthly variations were observed for soil moisture and hydraulic conductivity. It appears <i>C. decapetala</i> invasion affects some but not all soil physical properties; therefore, ecosystem recovery after <i>C. decapetala</i> removal can be spontaneous.</p>","PeriodicalId":7844,"journal":{"name":"African Journal of Ecology","volume":"63 2","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/aje.70036","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}