Research Articles (Zoology and Entomology)
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Item Tracing nutrient allocation in capital breeding baleen whales using amino acid stable isotope analysis: a novel method to infer protein balance and reproductive statusBusquets-Vass, Geraldine; Carroll, Emma L.; Lübcker, Nico; Constantine, Rochelle; Childerhouse, Simon; Baker, C. Scott; Dunshea, Glenn; Hindell, Mark; Cranswick, Annabelle; Lundquist, David; Newsome, Seth D. (Springer, 2025-11)Assessing reproductive status and the nutrient allocation strategies animals use to reproduce is integral for evaluating their vulnerability to environmental change; however, the elusive nature of many animals hinders our ability to assess the impact of these vital life history events on homeostasis. We developed a proxy for assessing protein balance in capital-breeding southern right whales (Eubalaena australis) based on carbon (δ13C) and nitrogen (δ15N) stable isotope analysis of amino acids (AA) in skin biopsy samples (n = 82) collected from free-ranging whales. Most AA in lactating females (cows) had higher δ13C but lower δ15N values in comparison to adult non-lactating females and adult males, suggesting they route fat stores for milk production and use protein reserves to maintain tissues. Lower AA δ15N values are likely associated with protein sparing and/or modifications to the urea cycle to retain or recycle nitrogen during reproduction. Nursing calves had distinctive AA δ13C and δ15N patterns compared to cows and adults, likely driven by the acquisition of protein from milk and the use of maternal resources in utero to support the high metabolic demands associated with rapid growth. Adult males and non-lactating adult females had nearly identical AA δ13C and δ15N patterns, suggesting they use similar nutrient allocation strategies while fasting. Patterns in δ13C and δ15N values among AA yielded correct classification of demographic groups with 98% accuracy and identification of lactating cows with 100% accuracy, showing that this new method holds promise for identifying the reproductive status of capital breeding mammals.Item Southern Africa : a united region with disparate invasive crayfish management legislation and policiesMadzivanzira, Takudzwa C.; Chakandinakira, Adroit T.; Andriantsoa, Ranja; Nawa, Nawa; Zvavahera, Munetsi; Machingura, James; Goza, David; Stacha, John T.; Marufu, Lightone T.; Barkhuizen, Leon M.; Mhlanga, Lindah; Nhiwatiwa, Tamuka; Zengeya, Tsungai Alfred; Dalu, Tatenda; South, Josie (Wiley, 2026-09)Coherence in national legislation and regional agreements is crucial in managing invasive species. Southern Africa is lacking the management capacity for postestablishment intervention of crayfish and therefore relies on successful biosecurity policy between countries with shared watersheds and land borders. Here, we examine the current state of national and transnational legislation regarding crayfish invasions in Southern Africa. Specifically, this study analysed the legal instruments governing invasive crayfish management across 10 Southern African states. The study revealed a clear disparity in legislative coherence between the countries. South Africa, which has a strong history of invasive species awareness, has clear and comprehensive legislation in comparison with many others, which lack updated regulatory frameworks that explicitly regulate invasive crayfish. The scarcity of data on the negative impacts of crayfish in Africa means that many policy documents are unclear as to whether crayfish should be described as established non-native or invasive non-native. Regional agreements also do not directly prohibit invasive crayfish movement across boundaries, which is a cause for concern as most invasions in the region have occurred as a result of limited monitoring in shared river basins. Although some states in the region are trying to prevent, control or manage the introduction of invasive crayfish species, others such as Madagascar are deriving socio-economic benefits from their presence. This creates the potential for policy contradictions across transboundary river basins. The unhindered expansion of crayfish invasions throughout the region serves as a stark reminder of the importance of early regional cooperation, updated specific policies and scientific research to mitigate the ecological and socio-economic threat posed by invasive crayfish and the protection of aquatic ecosystems in southern Africa.Item Quambalaria spp. : emerging tree pathogens of concernJamieson, Brittney-Aiden; Paap, Trudy; Pegg, Geoff S.; Carnegie, Angus J.; Wingfield, Michael J.; Roux, Jolanda; Hardy, Giles ESt J.; Drenth, Andre; Hammerbacher, Almuth; Bose, Tanay (Springer, 2026-05-23)PURPOSE OF REVIEW : Quambalaria spp. are fungal pathogens originating from Australian eucalypt species that are becoming increasingly important globally. For example, Quambalaria eucalypti, which was once considered a minor pathogen, now poses a significant threat to plantation productivity and forest health across continents. Their spread has been made possible through the expansion of eucalypt plantation forestry outside Australia, the movement of plant material and the increase in travel and trade, which facilitates the intercontinental movement of pathogens. This review summarises current knowledge regarding the taxonomy, distribution, life cycle and ecological and commercial impacts of Quambalaria spp. and some considerations for their control. RECENT FINDINGS : Recent studies have discovered new species of Quambalaria and there is emerging evidence of host shifts to other genera in the Myrtaceae. Outbreaks in Brazil, China, Indonesia and South Africa illustrate the rapid spread of Quambalaria spp. to new plantation environments. These pathogens threaten eucalypt plantations worldwide because clonal propagation reduces tree diversity and the trade of plant material facilitates their spread. Evidence of sexual reproduction has been identified in one species, Quambalaria pitereka, alluding to a high evolutionary potential. Although new molecular diagnostics and resistance screening tools are emerging, their use in the control of these pathogens remains limited. SUMMARY : Quambalaria spp. are important tree pathogens that are increasing their impact beyond their ancestral home in Australia. Their impact on plantation forestry and native forests underscores the broader vulnerabilities of forest ecosystems. Mitigating their impact will require integrated approaches that combine resistance breeding, enhanced surveillance, stringent quarantine measures, integrated disease management and changes to silviculture. Further research into host range, infection biology and pathogen evolution and the development of effective disease control is essential to safeguard global forests and ensure sustainable plantation forestry.Item Prof Stephen P. Long, FRS (1950–2025)Álvarez-Filip, Lorenzo; Bai, Edith; Bernacchi, Carl J.; Bruno, Rhea; Butterbach-Bahl, Klaus; Byrne, Maria; Chen, I-Ching; Chen, Shaolin; Cheung, William W.L.; Cotrufo, M. Francesca; Dalu, Tatenda; Feng, Xiaojuan; Fu, Yongshuo; Gao, Yanli; Huszar, Vera L.M.; Janssens, Ivan A.; Jeong, Sujong; Jones, T. Hefin; Joseph, Stephen D.; Khanna, Madhu; Kirschbaum, Miko U.F.; Kobayashi, Kazuhiko; Laroche, Julie; Leakey, Andrew D.B.; Li, Xinhai; Li, Yin; Liu, Lingli; Lohila, Annalea; Luo, Yiqi; McKechnie, Andrew E.; Monadjem, Ara; Nolan, Rachael H.; Pearson, Richard G.; Peng, Shushi; Peñuelas, Josep; Piao, Shilong; Robinson, Sharon A.; Ryu, Youngryel; Sage, Rowan F.; Shekar, Rachel G.; Xue, Shuai; Smith, Pete; Souza, Glaucia Mendes; Spatari, Sabrina; Suggett, David J.; Wang, Guangce; Way, Danielle A.; Wu, Jin; Xia, Longlong (Wiley, 2025-12)No abstract available.Item Back home : first successful geographical assignment of rehabilitated leopard tortoises Stigmochelys pardalis using a conservation genetic databaseArmstrong, Adrian J.; Kropff, Anna S.; Kotze, Antoinette; Whitehead, Wade; Goosen, Elishia; Ihlow, Flora; Monadjem, Ara; Padidar, Sara; Vamberger, Melita (Springer, 2026-03-21)Illegal trade in leopard tortoises Stigmochelys pardalis is widespread, yet the origins of confiscated S. pardalis are often unknown. Accurate assignment to source populations is essential for informed conservation management and release. We expanded and tested a genetic reference database for assigning S. pardalis to their original wild populations in KwaZuluNatal Province, South Africa, and Eswatini. We added 50 newly genotyped wild S. pardalis sampled across these regions to the database and then evaluated the updated database by sampling and assessing 50 S. pardalis of unknown geographic origin held at a rehabilitation centre in KwaZulu-Natal. Genetic assignment indicated that only a single S. pardalis at the rehabilitation centre may have originated from KwaZulu-Natal, highlighting the extent of illegal trade, translocation, and possession of S. pardalis. Individuals of verified regional origin were subsequently rehabilitated and translocated for soft release at appropriate sites.Item First report of Melanterius inconspicuus (Coleoptera: Curculionidae: Cleogonini) from KwaZulu-Natal, South Africa, with observations of its development in black wattleNel, Wilma Janine; Barnes, Irene; Jali, Sandisiwe; Impson, Fiona; Oberprieler, Rolf G.; Hurley, Brett Phillip (Taylor and Francis, 2026)Melanterius is a large genus of small weevils that primarily feed on the seeds of Acacia species occurring in their native range in Australia. In the latter part of the 20th century, five seed-feeding Melanterius species were released against several weedy Acacia species in South Africa as biological control agents. In early 2024, Melanterius weevils were detected damaging the vegetative plant tissues of trees in a commercial black wattle (Acacia mearnsii) compartment in the KwaZulu-Natal, South Africa. Morphological identification and DNA sequencing revealed that the weevils represent the species Melanterius inconspicuus, which is not one of the five species introduced in South Africa. This finding represents the first record of this Melanterius species outside of its native range in Australia and infesting black wattle, as well as the first record of a Melanterius species infesting vegetative tissues.Item New tribes (Paraphytini, Coptorhinini) proposed for five African or Afro-Oriental dung beetle genera formerly classified in the tribe Ateuchini Perty, 1830 (Coleoptera: Scarabaeidae: Scarabaeinae)Scholtz, Clarke H.; Davis, Adrian L.V.; De Klerk, Hennie (Magnolia Press, 2025-10)Owing to discrepancies between phylogeny and tribal phenetic classification in the subfamily Scarabaeinae, a number of new or old tribes have recently been described or revalidated to resolve the differences. The present paper continues this process by proposing two new tribes for five out of six genera recorded from Africa that were formerly classified in the tribe Ateuchini Perty, 1830 (Pedaria Castelnau, 1832, excluded). These five genera are either restricted to Africa (three genera) or show a primarily Afro-Oriental distribution (two genera). We provide defining characters for the Paraphytini Scholtz, Davis & de Klerk, new tribe (genus: Paraphytus Harold, 1877) and Coptorhinini Scholtz, Davis & de Klerk, new tribe (genera: Coptorhina Hope, 1833; Sarophorus Erichson, 1848; Delopleurus Erichson, 1848; Frankenbergerius Balthasar, 1938). Photographs are provided of the type genera, Paraphytus and Coptorhina, plus species of the other three genera. Maps show the overall geographical distribution of the five genera, only one of which is frequently recorded in dung (Sarophorus). The other genera either breed in rotting logs (Paraphytus) or are mycetophages.Item Are all waterholes equal from a lion’s view? Exploring the role of prey abundance and catchability in waterhole visitation patterns in a savannah ecosystemDejeante, Romain; Loveridge, Andrew J.; Macdonald, David W.; Madhlamoto, Daphine; Chamaillé-Jammes, Simon; Valeix, Marion (Peer Community In, 2026-04-03)Prey abundance and catchability shape the spatial ecology of predators. Predators can select habitats where prey are more abundant to maximize encounter rate with prey or habitats where prey are more catchable to maximize prey capture. These hypotheses are commonly referred to as prey-abundance and prey-catchability hypotheses. Although these hypotheses are often tested at the landscape scale, little is known about how between-patch variations in prey abundance and catchability determine the space use of predators. In many savannah ecosystems, large herbivores aggregate around waterholes, which become hotspots of prey and their selection by predators is classically interpreted as supporting the prey-abundance hypothesis. Here, we investigated whether between-waterhole variations in prey abundance and catchability influence the frequency and duration of lion visits to waterholes, testing the prey-abundance and prey-catchability hypotheses at the resource-patch scale. We combined datasets on (1) lion movements recorded from GPS collars deployed on 20 adult males and 16 adult females between 2002 and 2015, (2) prey abundance evaluated from long-term, regular monitoring of waterholes and (3) prey catchability evaluated from remote-sensing satellite imagery of vegetation cover around waterholes in Hwange National Park (Zimbabwe). Lions did not use all waterholes in their territory equally: there was a high variability in the frequency and duration of visits. Surprisingly, between-waterhole variations in prey abundance and catchability only slightly explained these variations in frequency – and even less in duration – of lion visits to waterholes. Yet, the frequency of lion visits to waterholes decreased with the number of waterholes within their territory, and male lions more frequently visited the waterholes surrounded by more open habitats. We discuss the limits of our work, but also the ecological mechanisms that may explain these findings. First, lions and their prey are involved in a ‘shell-game’ that leads them to adopt unpredictable movement strategies. Second, lions have only access to a limited number of waterholes amongst which to distribute their hunting effort. Lastly, lions visit waterholes not only to hunt but also to interact with social mates and competitors. This work challenges the implicit assumption that all waterholes are the same from a lion’s view and calls for further studies investigating the drivers of the variability in lion visits at the resource-patch scale.Item The “too-few elephant problem” : quantitative analysis of historical elephant tree-toppling rates across AfricaArchibald, Sally; Courtenay, Anya P.; Mtsetfwa, Fezile; Da Silva, Domingos Fortunato P.F.; Bunney, Katherine; Guldemond, Robert Abraham Rene; Mograbi, Penny; Ransom, Caitlin; Ryan, Casey M.; Owen-Smith, Norman (Springer, 2026-08)Elephants were a major driver of tree stem mortality in Africa, but their impacts are now spatially constrained and they no longer topple trees across the continent. Thus, most African landscapes lack a key ecological agent that helped maintain diversity and functioning. Even ecologists living in Africa fail to anticipate the rampant destruction of trees that can occur when elephants live in and move through landscapes. If we can build in a consensus on the degree of above-ground tree turnover that is inherent in different contexts, it would inform restoration projects and ecological definitions of degradation. We collated empirical data on treefall in ecosystems with and without elephants and predicted past tree loss spatially. The metrics used (%trees or #trees ha−1) reveal assumptions about the processes controlling elephant damage. On average elephants knock down 5.4 [IQR 3.0–8.3] % of the trees in an ecosystem per annum. Mapping this into places that no longer contain elephants reveals the above-ground biomass turnover that would have been the norm for millennia before elephants were widely exterminated. On average, this is ~ 1/3 of woody biomass production but at a local scale it can often exceed production. There is an urgent need for better theory on elephant tree interactions, and restoration projects should embrace the rapid turnover dynamics these ecosystems evolved with.Item Global analysis suggests nitrogen deposition as an underestimated driver of vegetation greeningTrepel, Jonas; Atkinson, Joe; Baines, Oliver; Kerr, Matthew; Le Roux, Elizabeth; Rubin, Hannah; Svenning, Jens-Christian; Buitenwerf, Robert (Wiley, 2026-10)The local effects of atmospheric nitrogen deposition on plants are well established, yet a global empirical analysis of nitrogen deposition effects on vegetation dynamics is missing. Here, we assess how nitrogen deposition, alongside other global change drivers such as fire, and changes in temperature, precipitation and human land use, is related to changes in vegetation greenness (enhanced vegetation index; EVI) from 2001 to 2024, and whether protected areas (PAs) mitigate these impacts. We found that increases in greenness were strongly and positively linked to nitrogen deposition and this pattern held across major ecosystem types. Nitrogen deposition also had a larger coefficient estimate and explained more variation in the spatial pattern of vegetation greening than the other drivers, suggesting the association of greening with nitrogen deposition may be even stronger than with climate and land-use change. Although EVI increased slightly slower inside PAs, protection status did not alter the relationship between nitrogen deposition and greening. Our findings suggest atmospheric nitrogen deposition as a critical but often underestimated potential driver of global vegetation dynamics. Reducing nitrogen deposition, alongside greenhouse gas emissions and land-use pressures, is therefore essential for sustaining ecosystem functioning and biodiversity.Item High resolution data reveal fundamental steps and turns in animal movementsGunner, Richard M.; Wilson, Rory P.; Lurgi, Miguel; Borger, Luca; Redcliffe, James; Shepard, Emily L.C.; Holton, Mark D.; Crofoot, Margaret C.; Alagaili, Abdulaziz; Andrzejaczek, Samantha; Ariano-Sanchez, Daniel; Barbedette-Gerard, Thomas; Bennett, Nigel Charles; Bernard, Alice; Brown, Rowan; Cole, Nik; Creel, Scott; Cruz-Neto, Ariovaldo P.; Di Virgilio, Agustina; Duarte, Carlos M.; Eizaguirre, Christophe; Elliott, Kyle H.; Faltusova, Monika; Garel, Mathieu; Gillies, Natasha; Gleiss, Adrian C.; Goppert, Aoife; Gremillet, David; De Grissac, Sophie; Guilford, Tim; Hoareau, Maxime; Jessopp, Mark; Gomez-Laich, Agustina; Jezek, Milos; Lambertucci, Sergio A.; Marchand, Pascal; Marks, Nikki; Martins, Andreia; Meekan, Mark; Mizutani, Yuichi; Mortensen, Rasmus M.; Norman, Bradley M.; Ortega, Josue; Padget, Oliver; Painter, Michael; Ponchon, Aurore; Provost, Pascal; Prudor, Aurelien; Quintana, Flavio; Reinhardt, Stefanie; Reynolds, Samantha D.; Rosell, Frank; Ruiz-Miranda, Carlos R.; Ryan, Peter G.; Scantlebury, David Michael; Schoombie, Stefan; Scott, Rebecca; Silovsky, Vaclav; Steenbeek, Jeroen; Tatayah, Vikash; Toigo, Carole; Torrez, Lucia; Tremblay, Fred; Twining, Joshua P.; Yoda, Ken; Weimerskirch, Henri; Whelan, Shannon; Morales, Juan M.;; Potts, Jonathan R. (Wiley, 2026-05)Please read abstract in the article.Item Editorial : Sustainable management of Tuta absolutaOmar, Ahmad A.; Ajene, Inusa Jacob; Aslam, Hafiz Muhammad Usman; Khamis, Fathiya Mbarak (Frontiers Media, 2026-02-23)No abstract available.Item Fumigant toxicity of essential oils from chemotypes of curry tree (Murraya koenigii) against adult African malaria mosquito (Anopheles gambiae sensu stricto)Mang'era, Clarence M.; Khamis, Fathiya Mbarak; Hassanali, Ahmed; Mireji, Paul O. (Wiley, 2026-07-20)Please read abstract in the article.Item Semiochemicals and odorant receptors underlying potato cultivar susceptibility and resistance to potato tuber mothChen, Ruipeng; Hu, Wangtao; Hu, Qin; Yan, Junjie; Yin, Jiao; Khamis, Fathiya Mbarak; Gao, Yulin; Leal, Walter S. (National Academy of Sciences, 2026-04)Infestation of potato by the potato tuber moth (Phthorimaea operculella) varies markedly among cultivars, yet the chemical and molecular mechanisms underlying this variation remain poorly understood. Here, we combine field surveys, chemical ecology, functional genomics, and structural modeling to reveal how cultivar-specific volatile profiles shape moth oviposition behavior and pest outcomes. Field and laboratory assays identified marked differences in adult attraction, oviposition, and larval damage among potato cultivars, which correlated with distinct blends of emitted volatile organic compounds (VOCs). Behavioral analyses revealed that among other VOCs, trans-nerolidol and β-ionone act as attractants, whereas 3-carene and benzyl tiglate function as oviposition deterrents. Electrophysiological screening and heterologous expression deorphanized six female-biased odorant receptors (ORs), identifying three narrowly tuned receptors linked to cultivar susceptibility or resistance. PopeOR01, upregulated following mating, selectively detects the attractant trans-nerolidol, which is enriched in susceptible cultivars, whereas PopeOR15 and PopeOR73 are tuned to repellents benzyl tiglate and 3-carene, respectively, which are enriched in resistant cultivars. CRISPR/Cas9-mediated knockouts confirmed that PopeOR01 and PopeOR73 are essential for antennal detection and behavioral responses to their cognate ligands. AlphaFold3 modeling, molecular docking, and molecular dynamics simulations revealed conserved OR-Orco channel architecture and stable ligand-binding modes consistent with physiological and behavioral data. Together, our results establish a mechanistic link between potato cultivar chemistry, insect olfactory receptor function, and pest behavior, providing a molecular framework for sustainable, semiochemical-based management of the potato tuber moth. SIGNIFICANCE : Insect pests cause substantial losses in global food production, and their control often relies on chemical insecticides with environmental costs. Environmentally friendly alternatives, such as push–pull strategies that exploit plant-derived attractants and repellents, offer promising solutions but require a mechanistic understanding of insect–plant interactions. Here, we investigate the chemical ecology of the potato tuber moth, a major worldwide pest of potato. Through integrated field surveys, laboratory assays, and molecular analyses, we identify cultivar-emitted attractants and repellents and the olfactory receptors in gravid females that mediate host selection. These findings provide a foundation for cultivar-based and semiochemical-driven strategies to sustainably manage potato tuber moth populations.Item Multi-omics comparison of two emerging storage pests (Necrobia rufipes and Tribolium castaneum) of dried black soldier fly larvae productAjene, Inusa Jacob; Tanga, Chrysantus M.; Akutse, Komivi S.; Karanu, Samantha W.; Khamis, Fathiya Mbarak (Nature Research, 2026-01-05)The black soldier fly (BSF) larvae is a rich and promising source of alternative protein that continues to increasingly gain global traction as a functional ingredient for sustainable livestock and fish production. The key setback to postharvest processing of stored BSF larvae (BSFL) products is the significant damage caused by two notable storage pests (Tribolium castaneum and Necrobia rufipes). Here, we present a comparative analysis of the complete mitochondrial genomes and gut microbiome profiles of T. castaneum and N. rufipes. The study mitogenomes were similar in size and structure to other coleopteran mitogenomes. The gut microbiome profiles of the two pests showed a high abundance of bacteria in the Proteobacteria and Firmicutes phyla. However, T. castaneum had 78% more phyla represented within its microbiome than N. rufipes. The most abundant genera in T. castaneum were Staphylococcus and Streptococcus, while in N. rufipes, the dominant genera were Klebsiella and Synechococcus. We also identified the presence of potentially clinically harmful microbial genera (Stenotrophomonas maltophilia) in the gut of T. castaneum and N. rufipes in relatively high abundance. These results provide insight into potential harmful associations in the gut of the storage pest, picked from contaminated, poorly processed BSFL products.Item Importance of elephants for dung beetle biodiversity and ecosystem functionsGijsman, Finote; Nutter, Ciara M.; Khamis, Fathiya Mbarak; Ombura, Fidelis L.O.; Hutchinson, Matthew C.; Palmer, Todd M.; Goheen, Jacob R.; Miller, Scott E.; Pringle, Robert M. (American Association for the Advancement of Science, 2026-05)INTRODUCTION : Large mammals are disproportionately affected by human activities such as overhunting and land conversion. All species of megaherbivores—ecologically influential mammals 1000 kg or larger, such as elephants and rhinoceroses—are considered at risk of extinction, and local population declines and extirpations of these species have already profoundly altered many ecosystems. Insects are also declining in abundance and diversity, raising concerns that important ecosystem services such as pollination and waste recycling will diminish. Moreover, because co-occurring species are interlinked through complex networks of interactions, the extinction of one species can trigger declines and losses of others that depend on it (“coextinction”), leading to a snowballing collapse of biodiversity and ecosystem functions. Thousands of dung beetle species (Coleoptera: Scarabaeinae, Aphodiinae) feed on the feces of large mammals and may therefore be prone to coextinction, along with their multibillion dollar services. RATIONALE : Countless theoretical studies have investigated coextinction by computationally simulating the loss of species from ecological networks, showing that coextinction cascades stem from the removal of critical nodes—typically, species that are linked to many others as predators or food sources. However, there is little concrete evidence of coextinction in nature. There is similarly little in situ support for other predictions of ecological network analysis, such as that the most highly connected species are “keystones” that sustain biodiversity and functionality, or that generalists with broad dietary niches are less susceptible to coextinction than specialists. Following calls to confront these predictions with data from experiments that mimic extinction, we tested how a community of 179 dung beetle species responded to the simulated, experimental, and real-world removal of elephants and other large herbivores in East Africa. RESULTS : We measured dung beetles’ preferences for the dung of different herbivore species and constructed a network of beetle–mammal interactions. Dung beetles had an inordinate fondness for elephant dung, which was the most connected node in the network. Simulated elephant removal predicted the secondary extinction of 28% of dung beetle species. A 15-year experiment supported that prediction, with 23% fewer species, 51% less biomass, and 67% fewer individual dung beetles in plots where elephants were selectively excluded. Dung beetles with stronger preference for elephant dung were more likely to be absent in elephant exclosures. None of the smaller ungulate species had comparable effects. Landscape-scale surveys of areas where elephants had been displaced by high livestock densities revealed similar and even starker depletions of dung beetle abundance and biomass (66 to 93%). A final experiment showed that the depletion of dung beetles in elephant exclosures impaired two ecosystem services: dung decomposition and seed dispersal. CONCLUSION : Elephants act as a true keystone species by sustaining the abundance, diversity, and functioning of dung beetle communities with their prodigious defecations. Our findings uphold predictions of ecological network theory that have seldom been tested in nature and suggest a strategy for building a mechanistic, predictive understanding of coextinction. Although our work is consistent with prior speculation that coextinction contributes significantly to global biodiversity loss, we highlight the potential of species reintroductions and range expansions to combat these losses while deepening our understanding of how they occur.Item A multidisciplinary assessment of endocrine and morphometric correlates of lactation physiology in southern right whalesShuttleworth, Loraine; Ganswindt, Andre; Vermeulen, Els (Oxford University Press, 2026-03-27)Reproduction in long-lived, iteroparous mammals requires careful allocation of energetic resources. This is especially true in capital breeding species such as the southern right whale (Eubalaena australis), where reproductive success depends on body condition, as accumulated reserves must fuel the high energetic demands, especially during lactation. Understanding the physiological mechanisms underpinning maternal energy balance is therefore critical for assessing reproductive capacity and maternal investment strategies. This study combined body condition metrics derived from aerial photogrammetry with endocrine correlates (glucocorticoids and triiodothyronine; hormones associated with energy mobilisation and regulation of metabolism) measured in blubber biopsies to establish baseline measures of metabolic function in lactating southern right whales over the calving season (July–September). Analyses revealed a positive correlation between glucocorticoids and triiodothyronine, strongest in lactating females. A clear decline in both hormones was observed toward the end of the calving season, consistent with reduced maternal metabolic activity and corresponding to slowed calf growth rates. No significant differences in hormone concentrations were detected between demographic groups (n = 15 lactating females, n = 8 unaccompanied adults), nor maternal (n = 9 good condition, n = 3 poor condition) or calf body condition categories (n = 5 good condition, n = 7 poor condition), although this may relate to the study’s limited sample size. By linking endocrine profiles with body condition, this study provides novel physiological context for understanding maternal investment strategies in southern right whales. The findings highlight how intra-seasonal energetic demands are hormonally mediated during lactation and demonstrate the feasibility of integrating photogrammetry with endocrine monitoring in free-swimming baleen whales. Establishing these physiological baselines is critical for detecting early indicators of reproductive stress and for informing conservation strategies in recovering populations.Item Assessing translocation success or failure of the African buffalo (Syncerus caffer) in post-war Mozambique using species distribution modellingBento, Carlos Manuel; Cardoso, Paulo E; Beilfuss, Richard D.; Chimimba, Christian Timothy (Wiley, 2026-07)Post-war Mozambique provides a rare setting to evaluate ecological models of African buffalo (Syncerus caffer) translocation outcomes. Following severe declines caused by armed conflict, translocations were implemented to restore ecological functioning. We tested whether Species Distribution Modelling (SDM) with MaxEnt, combined with Mahalanobis climatic distance, can retrospectively explain success or failure and guide future planning. Using 369 filtered occurrence records (1994–2014) and seven uncorrelated ecogeographic variables, we generated Suitability Habitat Indices (SHIs) and assessed model performance (AUC = 0.957; TSS = 0.804). Translocation outcomes were compared between origin and destination sites using ΔSHI (SHIdestination − SHIorigin) and climatic dissimilarity. Successful translocations, defined as short-term establishment (survival, adaptation, reproduction), were linked to positive or near-zero ΔSHI values and often supported by interventions such as water provisioning or dam construction. Failures occurred when high-SHI sources were moved to low-SHI destinations without ecological compensation. Climatic distance provided supplementary explanatory power but showed weak correlation with outcomes, underscoring the primacy of SHI-based assessments. Importantly, movements across Mozambique's six zooregions revealed that intra-zooregional translocations were more feasible, while inter-zooregional transfers exposed buffalo to novel ecological thresholds requiring intensive management. These findings demonstrate that SDM-derived SHIs, integrated with climatic distance and zooregional boundaries, offer a transparent framework for evaluating translocation feasibility. Embedding SHI modelling within adaptive management and ecological engineering is essential for long-term restoration success in fragmented savanna landscapes.Item Thermal requirements and phenology modelling of a Drosophila suzukii population : implications for pest risk under a changing climateNdlela, Shepard; Azrag, Abdelmutalab G.A.; Awuor, Esther Owino; Farid, Ibrahim Maholidy; Mohamed, Samira Abuelgasim (Academy of Science of South Africa, 2026-08-12)Drosophila suzukii (spotted-wing drosophila) is an invasive pest causing significant economic losses in soft-skinned fruit crops globally. This study presents comprehensive temperature-dependent life table data and phenology models for an African D. suzukii population collected in Kenya. Developmental time, mortality, fecundity, and adult longevity were assessed under constant temperatures from 12 to 30 °C. Using Insect Life Cycle Modelling (ILCYM) software, linear and nonlinear models were applied to characterise the effects of temperature on life history traits. Additionally, spatial risk indices including Establishment Risk Index (ERI), Generation Index (GI), and Activity Index (AI) were mapped globally for current and future (2061–2080) climate scenarios. The models revealed developmental thresholds of 6.87–34.05 °C (egg-larva) and 9.13–31.97 °C (pupa), with optimal development and reproduction occurring between 20–27 °C. Mortality rates increased at thermal extremes, with minimal mortality near 19.9 °C. Peak intrinsic rate of natural increase (rm = 0.276 day-¹) and finite rate of increase (λ = 1.317) were observed at 27 °C, while population growth declined sharply above 30 °C. Mapped spatial risk indices indicate a largely unchanged pattern between current and future projections, with high risk areas in tropical regions and localised changes in intensity and also distribution. These findings are consistent with other studies which have also indicated that temperature-driven phenology influences the spatial risk patterns of most insects. Given the recent invasion and ongoing spread of D. suzukii in Africa, integrating empirical data with mechanistic modelling provides a robust framework to anticipate invasion risk and optimise surveillance and control under changing climatic conditions.Item Applying standardised methods to assess the potential risks of alien freshwater crayfish introductions to South AfricaBotha, Lee-Anne; Chimimba, Christian Timothy; Zengeya, Tsungai Alfred (South African National Biodiversity Institute, 2026-05-12)Alien freshwater crayfish have been widely introduced worldwide for aquaculture and the pet trade. Despite providing societal benefits, crayfish introductions are also known to cause adverse impacts in areas of introduction. This study used the recently developed Risk Analysis for Alien Taxa (RAAT) framework to assess the risk associated with 14 alien freshwater crayfish introductions in South Africa. Thirteen of the 14 species were assessed as high risk because they are likely to be introduced to South Africa and have the potential to cause major environmental impacts. Eight of these species are listed under the South African National Environmental Management: Biodiversity Act (NEM:BA) Alien and Invasive Species (A&IS) Regulations, which implies there is an obligation to manage them. This notion was supported by the recommendations from the risk analyses for Cherax cainii, C. tenuimanus and C. quadricarinatus. The two marron species (C. cainii and C. tenuimanus) have no known naturalised populations and are likely confined to aquaculture facilities. Cherax quadricarinatus is already widespread and control methods should focus on minimising spread, as eradication is no longer feasible. The recommendations from some of the risk analyses do not agree with the current listing under the A&IS Regulations. Procambarus clarkii is already known to be invasive but is not listed and there is anecdotal evidence that C. destructor, Faxonius limosus, F. rusticus, Pacifastacus leniusculus and Pontastacus leptodactylus are present in the pet trade and their presence needs to be verified. Crayfish can become conflict-generating alien species because they have both major negative impacts and socio-economic benefits. Therefore, the recommended management options aim to preserve benefits while limiting negative impacts by restricting the importation of high-risk species for new introductions and implementing interventions to prevent spread and minimise impacts for established introductions.