Research Articles (Zoology and Entomology)

Permanent URI for this collectionhttp://hdl.handle.net/2263/1740

A collection containing some of the full text peer-reviewed/ refereed articles published by researchers from
the Department of Zoology and Entomology

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Camera trap-based estimates reveal spatial variability in African clawless otter population densities and behaviour
(Cambridge University Press, 2025) Lewis, Candice B.; Majelantle, Tshepiso Lesedi; Haussmann, Natalie S.; Mcintyre, Trevor
Estimating the population size of shy and elusive species is challenging but necessary to inform appropriate conservation actions for threatened or declining species. Using camera-trap surveys conducted during 2017–2021, we estimated and compared African clawless otter Aonyx capensis population densities and activity times in six conserved areas in southern Africa. We used two different models to estimate densities: random encounter models and camera-trap distance sampling. Our results highlight a general pattern of higher estimated densities and narrower confidence intervals using random encounter models compared to camera-trap distance sampling. We found substantial variation in densities between study areas, with random encounter model estimates ranging between 0.9 and 4.2 otters/km2. Our camera-trap distance sampling estimates supported the relative density estimates obtained from random encounter models but were generally lower and more variable, ranging from 0.8 to 4.0 otters/km2. We found significant differences in otter activity patterns, with populations either being nocturnal, mostly nocturnal or cathemeral. As all study areas experience little human disturbance, our results suggest that there are large natural variations in otter densities and activity patterns between regions. When densities are converted to metrics that are comparable to previous studies, our estimates suggest that African clawless otter population numbers are generally lower than previously reported. This highlights a need for broader spatial coverage of otter population assessments and future studies to assess potential environmental drivers of spatial, and potentially temporal, variation in population numbers and activity patterns.
Camera trap assessment of bushpig (Potamochoerus larvatus)-domestic animal interactions and implications for pathogen transmission in rural habitats of Madagascar
(Elsevier, 2025-12) Rakotoarivony, Rianja; Payne, Ariane; Kassie, Daouda; Goodman, Steven M.; Andriamahefa, Alpha; Raliniaina, Modestine; Rakotozandrindrainy, Raphael; Jori, Ferran J.
In some rural areas of Madagascar, bushpigs (Potamochoerus larvatus) are reported to be attracted to human disturbed habitats and share the same environment with domestic animals, including pigs (Sus scrofa). Such cohabitation can facilitate the transmission of pathogens between bushpigs and other domestic animals. To assess bushpig-domestic animal interactions and their implications for pathogen transmission, 26 camera-traps were deployed for three months around 10 villages in two separate regions of western Madagascar. The camera-traps were positioned at animal attraction sites: trophic resources, resting areas, and water points, and captured 17,804 images. No direct interactions (simultaneous presence) between bushpigs and domestic species were observed after analysis of 2678 trap nights. However, 44 indirect interactions (non-simultaneous presence) were recorded. The median critical time window (CTW), calculated as the time interval between the consecutive presence of bushpigs and some domestic species, was 646 min [34–1412 min]) for pigs, 672 min for cats [range 44–886 min], and 690 min for cattle [range 584–765 min]. Such CTW estimates are shorter than the average survival rate of several infectious pathogens potentially present in the environment, including African swine fever virus, Mycobacterium bovis, and Toxoplasma gondii. Factors such as proximity to water sources and protected areas statistically increased the chances of these interactions. Our research provided novel information on the level of interaction between bushpigs and other domestic animals in anthropized rural areas and which can be used to design and implement strategies to mitigate the risk of pathogen spread at the wildlife/livestock/human interface. HIGHLIGHTS • First-ever study of bushpig-domestic animal spatio-temporal interactions in Madagascar, for which indirect contacts occur. • Frequent indirect interaction between bushpigs, cattle, and cats beyond domestic pigs. • Divergent activity patterns reduce direct bushpig-domestic pig contacts. • Pathogen transmission theoretically possible given environmental survival times.
Spatial spillover effects of smallholder households’ adoption behaviour of soil management practices among push–pull farmers in Rwanda
(MDPI, 2024-12-26) Kidoido, Michael M.; Agboka, Komi Mensah; Hailu, Girma; Belayneh, Yeneneh; Mutyambai, Daniel Munyao; Owino, Rachel; Kassie, Menale; Niassy, Saliou
Push–pull technology (PPT) integrates maize with the legume fodder Desmodium sp. and the border crop Brachiaria sp., aiming to enhance maize production in Rwanda. Despite its potential, the adoption of complementary soil management practices (SMP), vital for PPT’s success, remains low. This study employs spatial econometric methods to evaluate the determinants of SMP adoption and the interdependencies in decision-making among PPT-practicing farmers. We constructed a spatial weight matrix based on a global Moran’s I index and identified optimal model parameters through principal component analysis. Utilizing a spatial Durbin probit model (SDPM), we assessed the spatial interdependence of SMP adoption decisions among maize farmers. Our findings reveal significant spatial dependence in SMP adoption within a 1.962 km radius, with improved seed usage, household income, yield, farmer group membership and size of land cultivated being key factors positively influencing adoption. We propose a “nonequilibrium promotion strategy” to enhance SMP adoption, emphasizing the establishment of pilot regions to broaden outreach. Additionally, fostering technical training and selecting farmers with adequate resources as demonstration leaders can enhance spatial spillover effects. This research provides insights for developing policies to scale up push–pull technology in Rwanda and across Sub-Saharan Africa.
Paramyxo- and coronavirus diversity and host associations in non-volant small mammals : evidence of viral sharing
(Oxford University Press, 2025-05) Mortlock, Marinda; Geldenhuys, Marike; Keith, Mark; Rademan, Rochelle; Swanepoel, Lourens H.; Von Maltitz, Emil F.; Kearney, Teresa; Markotter, Wanda; wanda.markotter@up.ac.za
Rodents and other non-volant small mammals (like shrews) maintain major ecological and epidemiological roles as reservoirs of zoonotic pathogens. Their presence within human-modified landscapes and interfaces with people, wildlife, and livestock create frequent opportunities for viral spillover. Despite this, the pathogen diversity and true risk of viral transmission are poorly understood by these hosts in Africa. Here, we explored the diversity and host association of paramyxoviruses and coronaviruses in non-volant small mammals from South Africa through longitudinal and opportunistic sample collection and molecular detection of viral RNA and host genetic barcoding. A high diversity of viruses was identified, with prevalences of 11.9% and 1.79% for paramyxoviruses and coronaviruses, respectively. Five instances of coinfections involving multiple paramyxoviruses and a coronavirus were detected, as well as nine Bayesian-supported paramyxovirus host genus, subfamily, and family switching, signifying frequent unrestrained viral sharing. Though the zoonotic potential of these identified viruses is unknown, the frequency of host switching suggests that these viruses may be more prone to adaptation to new host species or utilize highly conserved entry mechanisms. This highlights the risks for potential cross-species transmission events to livestock, domestic animals, and people, warranting continued surveillance.
Lactate as a key energy source facilitating cooperative behaviour in helper Damaraland mole-rats
(Royal Society, 2025-07) Cumming, Gisele S.; Bennett, Nigel Charles; Scantlebury, David Michael; Hart, Daniel William; Jacobs, Paul Juan; nigel.bennett@up.ac.za
This study explores the metabolic factors that may aid in the division of labour in cooperatively breeding Damaraland mole-rat (Fukomys damarensis) colonies, particularly during digging activities. In these group-living mammals, both breeders and non-breeders participate in digging, among other cooperative tasks; however, non-breeding males and females (NBFs), often referred to as ‘helpers’, undertake this task at a higher frequency and engage in other energetically demanding activities more often than their breeding counterparts. We investigated how variation in glucose and lactate levels, two key energy substrates, relates to different levels of digging activity between breeders and non-breeders and how these metabolic patterns might underpin reproductive differences in activity and energy budgets. While both breeding females (BFs) and NBFs exhibited similar decreases in glucose levels after digging, lactate dynamics revealed a key distinction, NBFs experienced a significant drop in plasma lactate, suggesting lactate utilization. In contrast, BFs showed an increase in lactate, indicating its accumulation rather than utilization, potentially contributing to their reduced involvement in digging activity. These findings suggest that lactate recycling and metabolism may play a crucial role in sustaining prolonged physical exertion in NBFs, providing a potential physiological explanation for the division of labour in mole-rat colonies.
Varietal authentication of Brunello di Montalcino wine using a minimal panel of DNA markers
(MDPI, 2025-06) Kibor, Maxwell K.; Scali, Monica; Vignani, Rita
Wine DNA fingerprinting (WDF), retrieved from the amplification of a wider panel of Simple Sequence Repeat (SSR) marker mappings in the Vitis vinifera L. genome, was used to assess the monovarietal nature of Brunello di Montalcino wine. The reliability of the varietal assessment was carried out by estimating the PI values associated with resolutive unrooted dendrograms depicting the correct varietal nature of different wines. As few as five SSR DNA markers associated with a PI value of one over a million or less, PI ≤ 10−6, can identify the purity of Sangiovese against Merlot, Pinot Noir, Cabernet Sauvignon, Primitivo (Zinfandel), and genetic variants of the Sangiovese as plant references. WDF was used on other monovarietal wines obtained from Cabernet Sauvignon, Merlot, Chardonnay, and Pinot Noir to test the feasibility of the method. In blended wines, the test was able to trace the main varietal component in a three-variety blend, keeping the varietal fingerprint detectable when the main variety was at least 75% (v/v). The data confirm how local genetic variants of Sangiovese can be tracked in commercial wines, becoming, at wine makers’ demand, part of an evidence synthesis of geographical origin.
Exploring the diversity of leafrollers (Lepidoptera: Tortricidae) associated with eucalypts in South African forestry nurseries and plantations, with a new report of Strepsicrates sp.
(Taylor and Francis, 2024-11-08) Makunde, Privilege Tungamirai; Slippers, Bernard; Hurley, Brett P.; privilege.makunde@fabi.up.ac.za
A number of insect pests cause damage to eucalypts in South Africa. Their accurate identification is a key part of managing and controlling these pests. The aims of this study were to identify leafroller insect species in South African eucalypt nurseries and plantations, and to determine whether the species were native insects that had developed new host associations with eucalypts or introduced non-native species. A section of the mitochondrial cytochrome c-oxidase subunit 1 (CO1) gene of multiple specimens from nurseries and plantations was sequenced. The sequence data were compared and validated using sequences available in BOLD systems and GenBank databases. Results revealed the presence of an introduced non-native Strepsicrates sp. in both nurseries and plantations. In addition, the native species Choristoneura occidentalis and Eccopsis incultana were confirmed as present in plantations only and the native species Lozotaenia capensana was confirmed as present in one of the nurseries. Eucalypts are reported as host plants of C. occidentalis, E. incultana and Lozotaenia capensana for the first time. The findings contribute valuable insights into the identification and diversity of leaf rollers in eucalypt plantations in South Africa, with potential implications for pest management.
DNA sequence data confirms the presence of two closely related cypress-feeding aphid species on African cypress (Widdringtonia spp.) in South Africa
(Taylor and Francis, 2024-12) Wondafrash, Mesfin; Wingfield, Michael J.; Hurley, Brett Phillip; Slippers, Bernard; Mutitu, Eston K.; Jenya, Herbert; Paap, Trudy
Aphids in the genus Cinara (Hemiptera: Aphididae) are pests of coniferous trees globally. Some of these aphids have become invasive in various parts of the world and have led to significant economic and environmental damage. During surveys conducted as part of a sentinel plant project, severe aphid infestations were observed on Widdringtonia trees in the Kirstenbosch National Botanical Garden, Cape Town, South Africa. In addition, planted Widdringtonia wallichii Endl. ex Carrière trees within their natural range of the Cederberg Wilderness Area, Western Cape, South Africa were found infested with aphids. In this study, we investigated the species identity of the aphids using DNA sequence data for the mitochondrial cytochrome coxidase (COI) gene. The results revealed the presence of two closely related aphid species, the cypress aphid, Cinara cupressi (Buckton) and the cypress pine aphid, Cinara tujafilina (Del Guercio) infesting Widdringtonia spp. in South Africa. Both aphid species are alien to South Africa. While this is not the first report for either species in the country, the current study provides evidence of impact, with severe infestations leading to branch dieback and tree death. This finding supports the regulation of Cinara spp. in South Africa and highlights that management is urgently needed.
‘Megafire’—you may not like it, but you cannot avoid it
(Wiley, 2025-04) Linley, Grant D.; Jolly, Chris J.; Doherty, Tim S.; Geary, William L.; Armenteras, Dolors; Belcher, Claire M.; Bliege Bird, Rebecca; Duane, Andrea; Fletcher, Michael-Shawn; Giorgis, Melisa A.; Haslem, Angie; Jones, Gavin M.; Kelly, Luke T.; Lee, Calvin K.F.; Nolan, Rachael H.; Parr, Catherine Lucy; Pausas, Juli G.; Price, Jodi N.; Regos, Adrian; Ritchie, Euan G.; Ruffault, Julien; Williamson, Grant J.; Wu, Qianhan; Nimmo, Dale G.
AIM : The term ‘megafire’ is increasingly used to describe large fires worldwide. We proposed a size-based definition of megafire—fires exceeding 10,000 ha arising from single or multiple related ignition events. A recent perspective in Global Ecology and Biogeography argues against a size-based definition of megafire and suggest that the term is too emotive for scientific use. We highlight that many scientific terms originate from common terms. These terms are often defined once they enter the scientific lexicon, enhancing both scientific understanding and public communication. We argue that standardised definitions facilitate better prediction, preparation, and management of fire events. LOCATION : Worldwide. TIME PERIOD : 2022–2023. METHODS : We conducted an updated structured review of the term ‘megafire’ and its use and definition in the peer-reviewed scientific literature, collating definitions and descriptions and identifying the criteria frequently invoked to define the term. RESULTS : We demonstrate an increase in the use of ‘megafire’ in the scientific literature since our original definition in 2022, with many studies adopting the > 10,000 ha size-based criterion. MAIN CONCLUSIONS : We contend that abandoning the term is neither practical, possible, nor beneficial. Instead, consistent usage underpinned by clear definitions is essential. Adopting a clear, size-based definition of megafire strengthens clarity and comparability across research and management practices globally. Precision in terminology is crucial for advancing research, improving communication, and informing effective fire management and policy.
Taxonomic revision of African pipistrelle-like bats with a new species from the West Congolean rainforest
(Oxford University Press, 2025-06) Torrent, Laura; Juste, Javier; Garin, Inazio; Aihartza, Joxerra; Dalton, Desire L.; Mamba, Mnqobi; Tanshi, Iroro; Powell, Luke L.; Padidar, Sara; Mudarra, Juan Luis Garcia; Richards, Leigh; Monadjem, Ara
The taxonomic conundrum of pipistrelle-like or pipistrelloid bats remains one of the unsolved challenges posed by African Chiroptera. Historically, their cryptic morphology has led to a frequently confused classification and cast doubt on taxonomic arrangements at both genus and species levels. While molecular analyses and extensive reviews of specimens housed in collections worldwide have clarified many systematic relationships among pipistrelloid bats, some species still require validation, leaving gaps in our overall understanding of the systematics of the group. The Congo rainforest, one of Africa's least explored regions, remains underrepresented in systematic studies of pipistrelloid bats. In this study, we combine the use of two mitochondrial genes and cranial morphometric analyses to provide an updated perspective on African pipistrelloid bats, focusing on new material from Equatorial Guinea sampled over multiple years. We confirm the placement of Af. musciculus and Af. crassulus within the genus Afropipistrellus. The former was previously included in Hypsugo, while the latter lacked generic confirmation. Additionally, we describe a new species of Pipistrellus from Bioko Island, Central Africa, uncovered during systematic bat surveys in the region. Further surveys in the Congo rainforest are needed to unveil African bat diversity and its phylogenetic relationships fully.
Population status of the range-restricted Red Lark Calendulauda burra in a conservation area stronghold
(Taylor and Francis, 2024) Kemp, Ryno; Colyn, R.; Freeman, Marc Trevor; McKechnie, Andrew E.; andrew.mckechnie@up.ac.za
ENGLISH : Many desert birds are vulnerable to anthropogenic global warming and landscape transformation, particularly in the case of range-restricted species. We quantified suitable habitat and the current population of Red Larks Calendulauda burra (family Alaudidae), a range-restricted southern African species, in a conservation area thought to be one of the species’ strongholds — the Black Mountain Mine Conservation Area (BMMCA) in the Northern Cape, South Africa. We modelled habitat suitability and estimated home range sizes using telemetry data and kernel density estimates. Home range sizes did not differ between males (42.4 ± 28.3 ha; n = 5) and females (41.9 ± 31.3 ha; n = 5). Transect data and home range density models indicated densities of 0.086–0.127 individuals·ha-1 for adults in suitable habitat. An estimated 33.2% (30.2 km2) of the BMMCA is suitable habitat for Red Larks, suggesting a population of 232–382 individuals. This population estimate is equivalent to <50% of the population estimated for the BMMCA in 1989. Our findings here, combined with a recent analysis showing that much of the species’ range will become thermally unsuitable for its persistence by the end of the 21st century, suggest that urgent conservation action is needed to ensure the Red Lark’s future in coming decades.
Mesoherbivores alter their activity levels with elephant-induced habitat modifications and behavioral cues
(Wiley, 2025) Jones, Maggie M.; Fletcher, Robert J.; Kruger, Laurence; Monadjem, Ara; Roques, Kim; Wisely, Samantha; Simelane, Phumlile; Keller, Janessa; Nhlabatsi, Sanele; McCleery, Robert A.
The largest herbivore species are declining across the world, threatening the structure and function of ecosystems. While the effects of megaherbivores (herbivores with a body mass over 1000 kg) on vegetation structure and composition have been studied extensively, megaherbivores may also influence other taxa, including smaller herbivores with which they share dietary overlap. In African savannas, megaherbivores, particularly African elephants Loxodonta africana, may influence mesoherbivores in two different ways: 1) indirectly through changes in vegetation structure that shape forage availability and predation risk, and 2) directly through their presence, which may elicit fear responses due to a risk of antagonistic interactions from these dominant competitors. However, these mechanisms have yet to be isolated, and thus their relative impact on mesoherbivores is unknown. We conducted a field experiment to test the effects of both of these mechanisms on mesoherbivore activity by emulating elephant-induced habitat alterations and behavioral cues (vocalizations) related to their presence in a savanna in Mlawula Nature Reserve, Eswatini, a protected area where elephants are absent. We found that, overall, mesoherbivores limited their activity in areas with either type of elephant impact. However, individual species exhibited large variation in the magnitude and direction of their responses to elephant impacts, with smaller species typically exhibiting stronger avoidance of elephant-impacted areas. Furthermore, combination of both types of elephant impacts tended to influence mesoherbivores more strongly than habitat alterations or vocalizations alone, emphasizing the complex roles that megaherbivores play in these communities. These results provide new insights into the consequences of megaherbivore loss, an issue of high conservation concern, and can inform efforts to restore megaherbivores' roles in savannas. Such efforts could include both recreating the impacts of elephants on vegetation structure and behavioral cues like vocalizations to move mesoherbivores around the landscape, potentially altering the effects of herbivory on savanna vegetation.
Water economics of African savanna herbivores : how much does plant moisture matter?
(Wiley, 2025-04) Van Driessche, Jeremy A.; Chamaillé-Jammes, Simon; Nutter, Ciara M.; Potter, Arjun B.; Pringle, Robert M.; Long, Ryan A.
Water is an essential and often limiting resource that pervades all aspects of animal ecology. Yet, water economics are grossly understudied relative to foraging and predation, leaving ecologists ill-equipped to predict how the intensifying disruption of hydrological regimes worldwide will impact communities. For savanna herbivores, reliance on surface water can increase exposure to predators and competitors, and thus strategies that reduce the need to drink are advantageous. Yet, the extent to which increasing dietary water intake while decreasing water loss enables animals to forego drinking remains unknown. We studied water budgets of sympatric African savanna antelopes that differ in size, bushbuck (Tragelaphus sylvaticus, ~35 kg) and kudu (T. strepsiceros, ~140 kg). We hypothesized that both species compensate for seasonally declining water availability by increasing consumption of moisture-rich plants and reducing faecal water loss, and that these adjustments are sufficient for small-bodied—but not large-bodied—herbivores to avoid spending more time near permanent water sources as the dry season advances. We tested our predictions using temporally explicit data on antelope movements, diets, plant traits and drinking behaviour in Gorongosa National Park, Mozambique. Water content declined between the early and late dry seasons in roughly half of plant taxa consumed by antelope. Although both species reduced faecal water loss and shifted their diets towards relatively moisture-rich plants as the dry season progressed, dietary water intake still declined. Contrary to expectation, kudu reduced selection for surface water in the late dry season without adjusting total time spent drinking, whereas bushbuck increased selection for surface water. We developed a generalizable approach for parsing the importance of dietary and surface water for large herbivores. Our results underscore that variation in surface-water dependence is a key organizing force in herbivore communities, that simple allometric predictions about the behavioural and ecological consequences of this variation are unreliable. Understanding wildlife water economics is a research frontier that will be essential for predicting changes in species distribution and community composition as temperatures rise and droughts intensify.
Push-pull cropping system positively impacts diversity and abundance of springtails (Hexapoda: Collembola) as bioindicators of soil health
(Elsevier, 2024-09) Mutyambai, Daniel Munyao; Mutua, Johnstone Mutiso; Jalloh, Abdul A.; Niassy, Saliou; Dubois, Thomas; Khan, Zeyaur; Subramanian, Sevgan
Crop cultivation positively or negatively impacts soil biodiversity and associated ecological services. The push-pull technology (PPT), a climate-smart cereal-Desmodium spp.-Brachiaria spp. Companion cropping system, is known for providing nature-based solutions for pest and soil fertility challenges and has been practiced in sub-Saharan smallholder farmer fields for more than two decades. However, the extent to which this cropping system affects soil arthropod biodiversity in general and Collembola in particular is not well known. This study assessed the long-term effects of PPT on soil physicochemical properties, abundance, and diversity of Collembola communities, and soil biological quality (QBS) as indicators of soil health. Soil was collected from five maize monoculture and five push-pull smallholder farmer fields in western Kenya. Soil physicochemical properties were analysed using Walkley-Black and Bouyoucos hygrometer method. Collembola abundance and diversity were assessed following the Berlese funnel extraction method and morphological identification. Soil health was evaluated using a Collembola-based soil biological quality (QBS-c) index. Soil physicochemical properties significantly differed between push-pull and maize monoculture fields, with push-pull soils being less acidic, and having higher quantities of nitrogen and carbon. Compared to monoculture, push-pull soils had significantly higher number and diversity of Collembola, and QBS-c index values. Significant positive correlations were observed between Collembola abundance and soil pH, nitrogen, carbon, phosphorous, and electrical conductivity. This study provides experimental evidence that crop diversification through a push-pull cropping system soil legacies positively impacts Collembola abundance and diversity, serving as bioindicator of healthy soils.
Automating thermal limits : continuous, objective, and high-throughput thermal data for small mobile ectotherms
(Elsevier, 2025-04) Mallett, Sophie L.; Leahy, Lily; Vaughan, Ian P.; Klaftenberger, Tristan; Cerda, Xim; Wheatley, Lucy J.; Leyshon, Kester; King, Shane; Dawson, Will; Harrendence, Kelsey; Wilker, Icaro; Bishop, Tom R.
HIGHLIGHTS • Small ectotherms and ecosystems they support are threatened by climate change. • Current dry bath methods to record thermal data focus only on thermal extremes. • We compare thermal data on ants from dry baths and a locomotor activity monitor. • The LAM reliably predicts upper thermal limits but not lower. • The LAM generates continuous, objective, and higher-throughput thermal data.
Short communication : impact of rest intervals and habituation on electro-ejaculated semen quality in merino-type rams
(South African Society for Animal Science, 2024-12) O’Neill, H.A.; Scholtz, J.; Kruger, L.P.; Maqhashu, A.; Ganswindt, Andre
This study evaluated the effects of habituation and electro-ejaculation techniques on semen quality in merino-type rams in South Africa, aiming to refine the electro-ejaculation method to improve semen quality. Parameters assessed included semen volume, sperm motility, sperm viability, sperm concentration, sperm viscosity, sperm consistency, and sperm abnormalities. Forty mature (six- to eighttooth) merino-type rams, approximately two and a half to four years old, were randomly assigned to four groups: habituated with a 3-second rest (H3) (n = 10), non-habituated with a 3-second rest (N3) (n = 10), habituated with a 10-second rest (H10) (n = 10), and non-habituated with a 10-second rest (N10) (n = 10). Each group underwent a two-week habituation period to human presence before electroejaculation using a commercial device. Analysed semen samples showed no significant differences in semen volume (0.93–1.28 mL), sperm motility (75.2%–83.1%), sperm viability (73.1%–85.5%), sperm concentration score (3.45–3.83), sperm viscosity score (3.5–4.00), or sperm consistency score (3.5– 4.0). However, the H3 group had a higher percentage of sperm abnormalities (12.3%) compared to the N3 (6.11%) and H10 (6.7%) groups, indicating that a shorter rest interval may negatively impact semen quality. The study concludes that extending the rest interval to ten seconds can enhance semen parameters.
Host specificity and host stage preference of Psyllaephagus species (Hymenoptera: Encyrtidae) towards invasive eucalypt psyllids (Hemiptera: Aphalaridae)
(Wiley, 2025-08) Makunde, Privilege Tungamirai; Slippers, Bernard; Bush, Samantha J.; Hurley, Brett Phillip; privilege.makunde@up.ac.za
Invasive eucalypt psyllids pose a threat to the long-term production of eucalypts worldwide. In order to reduce their economic impact, classical biological control using Psyllaephagus species has been used successfully. The objectives of this study were to determine the host specificity and host stage preference of Psyllaephagus blastopsyllae, Psyllaephagus pilosus and Psyllaephagus bliteus using related eucalypt-feeding psyllids, Blastopsylla occidentalis, Ctenarytaina eucalypti, Glycaspis brimblecombei and Spondyliaspis cf. plicatuloides. To determine host specificity, three Psyllaephagus species were collected locally from their hosts. Five-day-old parasitoids were exposed to all five developmental stages (I–V) of host and non-host psyllids in choice and non-choice tests. Similar bioassays were used to assess parasitoid preferences for specific nymphal stages, identifying their preferred developmental stages of potential hosts. Glycaspis brimblecombei was identified as a potential host for P. blastopsyllae, and S. cf. plicatuloides as an alternate host for P. bliteus, though emergence rates were three to four times lower than for their known hosts. Psyllaephagus pilosus showed no interest in non-host psyllids. Female parasitoids displayed stage-specific preferences for both known and newly identified hosts. The current findings indicate that some Psyllaephagus species attack hosts within an ecological niche, whereas others are highly host specific. Additionally, the distinction between potential host range observed in laboratory conditions and ecological host range in field conditions should be considered, as laboratory tests typically exhibit a broader host range.
How much does light pollution alter vector disease transmission at scale?
(Wiley, 2025-07) Coetzee, Bernard Walter Thomas; Van Zyl, Layla
Artificial light at night (ALAN) is increasingly recognised as a global change driver due to its widespread use and ecological impacts. ALAN influences mosquitoes under laboratory conditions, altering the biting propensity of diurnal Aedes mosquitoes while suppressing that of nocturnal Anopheles species complexes, the primary malaria vectors in Africa. This study models ALAN's effects on mosquito vectorial capacity using the R package AnophelesModel, incorporating lab and field data on mosquito biting behaviour and light sources. Findings suggest ALAN may influence malaria transmission dynamics, underscoring the need for further investigation at household and larger ecological scales. However, small reductions in biting propensity alone mean ALAN has a smaller impact compared to other interventions.
Vectorial drivers of malaria transmission in Jabi Tehnan district, Amhara Regional State, Ethiopia
(Nature Research, 2024-06-13) Belay, Aklilu; Asale, Abebe; Sole, Catherine L.; Kinya, Fiona; Yusuf, Abdullahi Ahmed; Torto, Baldwyn; Mutero, Clifford Maina; Tchouassi, David P.
Among the factors affecting the effectiveness of malaria control is poor knowledge of the entomologic drivers of the disease. We investigated anopheline populations as part of a baseline study to implement house screening of windows and doors as a supplementary malaria control tool towards elimination in Jabi Tehnan district, Amhara Regional State of Ethiopia. The samples were surveyed monthly using CDC light traps between June 2020 and May 2021. Mosquito trap density (< 3 mosquitoes/trap) was low, however, with a high overall Plasmodium sporozoite rate (9%; indoor = 4.3%, outdoor = 13.1%) comprising P. falciparum (88.9%) and P. vivax (11.1%). Anopheles gambiae s.l., mostly An. arabiensis, comprised > 80% of total anopheline captures and contributed ~ 42% of Plasmodium-infected mosquitoes. On the other hand, morphologically scored Anopheles funestus s.l., constituting about 6% of anopheline collections, accounted for 50% of sporozoite-infected mosquitoes. Most of the infected An. funestus s.l. specimens (86.7%) were grouped with previously unknown or undescribed Anopheles species previously implicated as a cryptic malaria vector in the western Kenyan highlands, confirming its wider geographic distribution in eastern Africa. Other species with Plasmodium infection included An. longipalpis C, An. theileri, An. demillioni, and An. nili. Cumulatively, 77.8% of the infected mosquitoes occurred outdoors. These results suggest efficient malaria parasite transmission despite the low vector densities, which has implications for effective endpoint indicators to monitor malaria control progress. Additionally, the largely outdoor infection and discovery of previously unknown and cryptic vectors suggest an increased risk of residual malaria transmission and, thus, a constraint on effective malaria prevention and control.
The global atlas of edible insects : analysis of diversity and commonality contributing to food systems and sustainability
(Nature Research, 2024-02-29) Omuse, Evanson R.; Tonnang, Henri E.Z.; Yusuf, Abdullahi Ahmed; Machekano, Honest; Egonyu , James Peter; Kimathi , Emily; Mohamed, Samira Faris; Kassie , Menale; Subramanian , Sevgan; Onditi , Juliet; Mwangi , Serah; Ekesi , Sunday; Niassy, Saliou
The future of the food system on the planet is increasingly facing uncertainties that are attributable to population growth and a surge in demand for nutritious food. Traditional agricultural practices are poised to place strain on production, as well as natural resources and ecosystem services provided, particularly under a changing climate. Given their remarkable attributes, including a low environmental footprint, high food conversion ratio, rapid growth and nutritional values, edible insects can play a vital role in the global food system. Nonetheless, substantial knowledge gaps persist regarding their diversity, global distribution, and shared characteristics across regions, potentially impeding effective scaling and access to edible insects. Therefore, we compiled and analysed the fragmented database on edible insects and identified potential drivers that elucidate insect consumption, globally, focusing on promoting a sustainable food system. We collated data from various sources, including the literature for a list of edible insect species, the Global Biodiversity Information Facility and iNaturalist for the geographical presence of edible insects, the Copernicus Land Service library for Global Land Cover, and FAOSTAT for population, income, and nutritional security parameters. Subsequently, we performed a series of analytics at the country, regional and continental levels. Our study identifies 2205 insect species, consumed across 128 countries globally. Among continents, Asia has the highest number of edible insects (932 species), followed by North America (mainly Mexico) and Africa. The countries with the highest consumption of insects are Mexico (450 species), Thailand (272 species), India (262 species), DRC (255 species), China (235 species), Brazil (140 species), Japan (123 species), and Cameroon (100 species). Our study also revealed some common and specific practices related to edible insect access and utilisation among countries and regions. Although insect consumption is often rooted in cultural practices, it exhibits correlations with land cover, the geographical presence of potentially edible insects, the size of a country’s population, and income levels. The practice of eating insects is linked to the culture of people in Africa, Asia, and Latin America, while increased consciousness and the need for food sustainability are driving most of the European countries to evaluate eating insects. Therefore, edible insects are becoming an increasingly significant part of the future of planetary food systems. Therefore, more proactive efforts are required to promote them for their effective contribution to achieving sustainable food production.

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