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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Bacterial blood microbiome of Mastomys rodents : implications for disease spill-over at the animal-human interface within the Bushbuckridge-East community, South Africa
(Frontiers Media, 2025-02) Kolo, Agatha Onyemowo; Brayton, Kelly A.; Collins, Nicola E.; Bastos, Armanda D.S.; Matthee, Sonja; Gall, Cory A.; Wentzel, Jeanette Maria; Neves, L.C.B.G.D. (Luís); Oosthuizen, Marinda C.
The Bushbuckridge-East community in Mpumalanga Province, South Africa is bordered by nature reserves, including the Manyeleti Game Reserve. Murid rodents are prevalent in both Manyeleti and communal rangelands adjoining the community households. Although rodents are reservoir hosts for a broad range of viral, bacterial and parasitic pathogens, the rodent microbial diversity and transmission of zoonotic agents to humans in the community is understudied. In this study we investigated bacterial diversity in wild and commensal rodents sampled from different habitats. The 16S rRNA gene was amplified from DNA extracted from the blood of 24 wild Mastomys and one Steatomys sp. and subjected to PacBio circular consensus sequencing. As Bartonella species were dominant in the blood microbiome, gltA gene characterization was performed to delineate species. Rodents sampled from peri-urban and communal rangelands had higher proportions of Bartonella spp. [Hlalakahle (77.7%), Gottenburg (47.8%), Tlhavekisa (83.8%)] compared to those from the protected habitat (43.8%). Ehrlichia spp., Anaplasma spp., and Coxiella burnetii were detected at <1% of the sequence reads. Conventional PCR and sequencing validated the detection of Bartonella spp. with the first confirmation of Bartonella mastomydis infection in Mastomys in South Africa. Additionally, 317 mites, 90 fleas, 10 ticks and eight lice were collected from the rodents, providing evidence of possible vectors of the organisms detected. The detection of zoonotic agents in rodents in Bushbuckridge-East community, together with prior serological confirmation of Bartonella and Coxiella in non-malarial acute febrile patients from this community, highlights the possible risks that commensal rodents pose to human health.
Widening global variability in grassland biomass since the 1980s
(Nature Research, 2024-10) MacDougall, Andrew S.; Esch, Ellen; Chen, Qingqing; Carroll, Oliver; Bonner, Colin; Ohlert, Timothy; Siewert, Matthias; Sulik, John; Schweiger, Anna; Borer, Elizabeth T.; Naidu, Dilip; Bagchi, Sumanta; Hautier, Yann; Wilfahrt, Peter; Larson, Keith; Olofsson, Johan; Cleland, Elsa; Muthukrishnan, Ranjan; O'Halloran, Lydia; Alberti, Juan; Anderson, T. Michael; Arnillas, Carlos A.; Bakker, Jonathan D.; Barrio, Isabel C.; Biederman, Lori; Boughton, Elizabeth H.; Brudvig, Lars A.; Bruschetti, Martin; Buckley, Yvonne; Bugalho, Miguel N.; Cadotte, Marc W.; Caldeira, Maria C.; Catford, Jane A.; D'Antonio, Carla; Davies, Kendi; Daleo, Pedro; Dickman, Christopher R.; Donohue, Ian; Dupre, Mary Ellyn; Elgersma, Kenneth; Eisenhauer, Nico; Eskelinen, Anu; Estrada, Catalina; Fay, Philip A.; Feng, Yanhao; Gruner, Daniel S.; Hagenah, Nicole; Haider, Sylvia; Harpole, W. Stanley; Hersch-Green, Erika; Jentsch, Anke; Kirkman, Kevin; Knops, Johannes M.H.; Laanisto, Lauri; Lannes, Luciola S.; Laungani, Ramesh; Lkhagva, Ariuntsetseg; Macek, Petr; Martina, Jason P.; Mcculley, Rebecca L.; Melbourne, Brett; Mitchell, Rachel; Moore, Joslin L.; Morgan, John W.; Muraina, Taofeek O.; Niu, Yujie; Paertel, Meelis; Peri, Pablo L.; Power, Sally A.; Price, Jodi N.; Prober, Suzanne M.; Ren, Zhengwei; Risch, Anita C.; Smith, Nicholas G.; Sonnier, Gregory; Standish, Rachel J.; Stevens, Carly J.; Tedder, Michelle; Tognetti, Pedro; Veen, G.F. (Ciska); Virtanen, Risto; Wardle, Glenda M.; Waring, Elizabeth; Wolf, Amelia A.; Yahdjian, Laura; Seabloom, Eric W.
Global change is associated with variable shifts in the annual production of aboveground plant biomass, suggesting localized sensitivities with unclear causal origins. Combining remotely sensed normalized difference vegetation index data since the 1980s with contemporary field data from 84 grasslands on 6 continents, we show a widening divergence in site-level biomass ranging from +51% to −34% globally. Biomass generally increased in warmer, wetter and species-rich sites with longer growing seasons and declined in species-poor arid areas. Phenological changes were widespread, revealing substantive transitions in grassland seasonal cycling. Grazing, nitrogen deposition and plant invasion were prevalent in some regions but did not predict overall trends. Grasslands are undergoing sizable changes in production, with implications for food security, biodiversity and carbon storage especially in arid regions where declines are accelerating.
Memory-based navigation in elephants : implications for survival strategies and conservation
(MDPI, 2025-04) Morel, Margot; Guldemond, Robert Abraham Rene; De la Garza, Melissa A.; Bakker, Jaco; robert.guldemond@up.ac.za
SIMPLE SUMMARY : Elephants exhibit exceptional memory capabilities, allowing them to adapt to environmental changes and human presence. Their ability to remember the locations of water, food, and safe pathways helps them survive in increasingly fragmented landscapes. Older elephants, especially matriarchs, play a key role in leading herds, yet how knowledge is transferred to younger generations remains uncertain. Conservation strategies can benefit from understanding elephant movement patterns by preserving migratory routes, ensuring access to essential resources, and mitigating human–elephant conflict. Protecting experienced individuals is vital, as their loss may disrupt herds and decrease survival chances. Elephants also shape ecosystems by dispersing seeds and maintaining habitat diversity, making them essential for biodiversity and climate resilience. By aligning conservation efforts with their natural behaviours, such as establishing wildlife corridors, reducing conflicts with farmers, and considering elephant decision-making in habitat planning, humans can foster coexistence while preserving these keystone species. Future research should focus on how elephants develop spatial knowledge and adapt to rapid environmental changes. Understanding their navigation strategies is key to ensuring their survival and maintaining the ecosystems they help sustain.
Review and meta-analysis of correlates of home range size in bats
(Oxford University Press, 2024-10) Wood, Matthew Roger; De Vries, J. Low; Monadjem, Ara; Markotter, Wanda; wanda.markotter@up.ac.za
Home range is an ecological concept that affects many aspects of the life of vertebrates and hence understanding how it varies between species is crucial. Mammalian home range size has been linked to body size and diet, but these studies were based predominantly on terrestrial species and most specifically excluded bats. As the only group of flying mammals, bats experience distinctly different constraints on movement, and hence home range. However, despite their diversity, relatively little is known about the home ranges of bats, and this is the first global review assessing correlates of their home range size. Our hypothesis is that home range will be impacted by different ecological conditions experienced by the bats and by the biological traits of the bats themselves. We performed a meta-analysis based on published data for 81 bat species to identify variables that contribute most to home range size. Sex, wing loading, functional group, colony size, dietary class, distance from the equator (latitudinal region), habitat type, and the interaction between habitat type and latitudinal region were all important explanatory variables. Wing loading was positively correlated with home range size—while females, open-air foragers, large colony sizes, and bats in temperate regions consistently had large home ranges. Understanding the correlates of home range has important implications, for example, for bat conservation and for assessing the risk of spillover of zoonotic pathogens from bats to humans and livestock.
One Health interventions and challenges under rural African smallholder farmer settings : a scoping review
(Elsevier, 2025-06) Omuse, Evanson R.; Machekano, Honest; Sokame, Bonoukpoe M.; Mutyambai, Daniel M.; Dubois, Thomas; Subramanian, Sevgan; Chidawanyika, Frank
The global human population is rapidly increasing, escalating interactions of people, animals and the environment. This has led to more convoluted health challenges, for which African smallholder farmers bear the brunt. The One Health (OH) approach recognises the interconnectedness of these health challenges and thus follows a transdisciplinary approach involving diverse stakeholders to address them. Although there have recently been global concerted efforts and studies on OH, an information gap exists in Africa, particularly regarding smallholder farmers and their needs. Additionally, evaluation frameworks and outcome metrics for OH initiatives are still unclear. Thus, this study was conducted to critically map the available evidence of OH initiatives in the lens of African smallholder settings and identify gaps and opportunities for optimally targeted interventions. An extensive article searches yielded 1479 references, with only 21 studies from 11 countries qualifying for this review. Implementation of OH initiatives involved the collaboration of diverse stakeholders at local, national, regional and global levels. Most of the reported stakeholders of the OH initiatives were largely UN agencies, CGIAR centres, non-governmental organizations and universities. More than half of the studies focused on zoonotic and human-animal shared diseases. Conversely, few studies focused on human or animal food and nutrition security; land degradations; livelihoods and well-being; antimicrobial resistance, water sanitation and hygiene; food safety; soil health; crop health; biodiversity loss; climate change and gender equity. Effective capacity building, risk mitigation, social benefits, economic benefits, improved animal health and welfare, improved human health and well-being and improved ecosystem health and resilience were identified as OH outcomes. Based on the many evidence gaps, the OH initiatives must address health challenges mostly encountered by smallholder farmers with an increased focus on food security and safety, especially under the ongoing climate change. However, the successful implementation of OH initiatives was constrained by weak governance and coordination structures, poor communication and information sharing, lack of integrated surveillance system, limited community engagement, lack of political will, inadequate resources and logistical support, limited multi-disciplinarity and divergent priorities. Additionally, the lack of consensus on evaluation framework and outcomes highlights the need for an integrated standard framework for developing and implementing OH initiatives and harmonised outcome evaluation metrics to avoid under- or over-estimation of OH benefits.
Good moms : dependent young and their mothers cope better than others with longer dry season in plains zebras
(Springer, 2025-03) Thel, Lucie; Bonenfant, Christophe; Chamaillé-Jammes, Simon
In large herbivores, the timing of births often coincides with the seasonal peak of food resources availability, likely to improve juvenile survival and reduce reproduction costs. Some species, however, breed year-round, even in seasonal environments. Demographic processes, such as to what extent being born during the lean season reduces survival of juveniles and reproductive females, remain understudied in large mammals inhabiting tropical ecosystems. We investigated survival rates in plains zebras (Equus quagga) in Hwange National Park (Zimbabwe), a highly seasonal savanna ecosystem. We used capture–recapture models to analyse long-term demographic data (2008–2019). We investigated the effect of seasonality as a categorical (wet versus dry season) and continuous (duration of the dry season) variable on survival. We found little variability in early juvenile survival (φ = 0.458 ± 0.044 SE, < 6 m.o.), whereas late juvenile and yearling survivals were higher and decreased with increasing length of the dry season (from 0.850 ± 0.095 SE to 0.480 ± 0.120 SE). Female survival was high (> 0.703 ± 0.057 SE and up to 0.995 ± 0.006 SE) but decreased with exposure to the dry season in non-reproductive females. The probability of females becoming reproductive in the following year was not affected by the length of the dry season (0.423 and 0.420 for reproductive and non-reproductive females, respectively). Our results highlight the importance of individual quality in reproductive performance, as reproductive females seem to buffer the effect of environmental variability on their own survival and that of their foal.
Falconer perceptions of, and support for, rabbit hemorrhagic disease biosecurity actions
(Utah State University, 2023) Shapiro, Hannah G.; Pienaar, Elizabeth Frances
Rabbit hemorrhagic disease virus 2 (RHDV2) is a highly contagious virus that primarily infects wild and domestic rabbits and hares (lagomorphs). In the United States, state wildlife agencies rely on stakeholders to report RHDV2-related mortalities and engage in voluntary biosecurity actions to prevent the spread of RHDV2. However, stakeholder perceptions of RHDV2 and relevant biosecurity actions have not been evaluated. We conducted the first study in the United States on how falconers’ risk perceptions, knowledge, trust in state wildlife agencies to manage RHDV2, hunting behaviors, and demographic characteristics influenced their willingness to engage in voluntary biosecurity actions and support potential government-mandated biosecurity measures. To complete our study, we surveyed 480 falconers in 45 states using an online questionnaire from April 2021 to March 2022. Most respondents were aware of RHDV2 but did not know about the multiple vectors for RHDV2 transmission or that infected lagomorphs are unlikely to show signs of disease. Most respondents were willing to engage in all voluntary biosecurity actions (52.9–89.8%) and supported 3 of the 4 RHDV2 management strategies (56.0–62.5%). Respondents’ willingness to engage in or support biosecurity measures depended on the importance they placed on biosecurity, their risk perceptions, and their trust in state wildlife agencies to manage RHDV2. Consistent, up-to-date outreach efforts should communicate the economic and hunting risks associated with RHDV2 and how falconer adoption of biosecurity behaviors may lower the risk of human-mediated RHDV2 spread. State wildlife agencies may build trust with falconry groups by actively engaging falconers in lagomorph and RHDV2 monitoring efforts and working with falconers to implement biosecurity measures that are safe for raptors while also lowering the risk of human-mediated RHDV2 spread.
IMA GENOME-F20 a draft genome assembly of Agroathelia rolfsii, Ceratobasidium papillatum, Pyrenopeziza brassicae, Neopestalotiopsis macadamiae, Sphaerellopsis filum and genomic resources for Colletotrichum spaethianum and Colletotrichum fructicola
(Pensoft Publishers, 2025-02) D’Angelo, Davide; Sorrentino, Roberto; Nkomo, Tiphany; Zhou, Xianzhi; Vaghefi, Niloofar; Sonnekus, Byron; Bose, Tanay; Cerrato, Domenico; Cozzolino, Loredana; Creux, Nicky; D'Agostino, Nunzio; Fourie, Gerda; Fusco, Giovanna; Hammerbacher, Almuth; Idnurm, Alexander; Kiss, Levente; Hu, Yanping; Hu, Hongli; Lahoz, Ernesto; Risteski, Jason; Steenkamp, Emma Theodora; Viscardi, Maurizio; Van der Nest, Magrieta Aletta; Wu, Yuan; Yu, Hao; Zhou, Jianjin; Dewage, Chinthani S. Karandeni; Kotta-Loizou, Loly I.; Stotz, Henrik U.; Fitt, Bruce D.L.; Huang, Yong-Ju; Wingfield, Brenda D.; brenda.wingfield@up.ac.za
Southern Ocean food-webs and climate change : a short review and future directions
(Public Library of Science, 2024-03-11) Queiros, Jose P.; Borras-Chavez, Renato; Friscourt, Noemie; Groß, Jasmin; Lewis, Candice B.; Mergard, Georgia; O’Brien, Katie
Food-webs are a critical feature of ecosystems and help us understand how communities will respond to climate change. The Southern Ocean is facing rapid and accelerating changes due to climate change. Though having evolved in an isolated and somewhat extreme environment, Southern Ocean biodiversity and food-webs are among the most vulnerable. Here, we review 1) current knowledge on Southern Ocean food-webs; 2) methods to study foodwebs; 3) assessment of current and future impacts of climate change on Southern Ocean food-webs; 4) knowledge gaps; and 5) the role of Early Career Researchers (ECRs) in future studies. Most knowledge on Southern Ocean food-webs come from the pelagic environment, both at macro- and microbial levels. Modelling and diet studies of individual species are major contributors to the food-web knowledge. These studies revealed a short food-web, predominantly sustained by Antarctic Krill (Euphausia superba). Additionally, alternative pathways exist, involving other krill species, fish, and squid, which play equally important roles in connecting primary producers with top predators. Advantages and disadvantages of several techniques used to study Southern Ocean food-webs were identified, from the classical analyses of stomach contents, scats, or boluses to the most recent approaches such as metabarcoding and trophic-biomarkers. Observations show that climate change can impact the foodweb in different ways. As an example, changes to smaller phytoplankton species can lengthen the food-web, increasing assimilation losses and/or changing nutrient cycles. Future studies need to focus on the benthic-dominated food-webs and the benthopelagic coupling. Furthermore, research during the winter season and below the ice-shelves is needed as these areas may play a crucial role in the functioning of this ecosystem. ECRs can play a significant role in advancing the study of Southern Ocean food-webs due to their willingness for interdisciplinary collaboration and proficiency in employing various methodologies, contributing to the construction of high-resolution food-webs.
Transgenerational cross-susceptibility to heat stress following cold and desiccation acclimation in the angoumois grain moth
(Wiley, 2024-12) Mpofu, Precious; Machekano, Honest; Airs, Paul M.; Nyamukondiwa, Casper
The Angoumois grain moth, Sitotroga cerealella (Olivier), is a significant cosmopolitan primary pest of cereals worldwide and has thrived in divergent environments. However, the mechanisms underlying its survival in multiple contrasting environments are poorly understood. Here, we hypothesised that when facing diverse environmental stress, F1 generation exhibits transgenerational cross-protection as a mechanism to persist under divergent stressful environments. Notably, F1 acclimation to cold or desiccation conditions could either enhance or lower heat tolerance in the F2 generation. Specifically, we tested whether typical diurnal fluctuations and/or winter rapid or chronic cold temperatures (18–22 C) as well as desiccation acclimation of F1 parental population yields transgenerational cross-protection/susceptibility to heat stress on F2 offspring. F1 moths were exposed to cold hardening (2 h), chronic (72 h) and variable (fluctuating between 18 and 22 C for 72 h) temperature treatment groups. Desiccation treatment included incubation at 0%–1% relative humidity (24 h). F2 generation moths were then assessed for heat tolerance using critical thermal maxima (CTmax) at three different ramping rates (0.06, 0.25 and 0.5 C/min) as well as heat knockdown time (HKDT). Findings indicated that (i) desiccation, cold hardening and chronic low-temperature acclimations in F1 reduced heat tolerance in F2 populations and (ii) ramping rate was crucial to decipher differences between treatment groups, with lower ramping rates associated with lower CTmax. Transgenerational cross-susceptibility to heat stress indicates possible fitness costs of exposure to multiple contrasting stressors in the Angoumois grain moth and can be used in designing physical pest management strategies.
Successful alien plant species exhibit functional dissimilarity from natives under varied climatic conditions but not under increased nutrient availability
(Wiley, 2025-03) Milanovic, Marija; Bakker, Jonathan D.; Biederman, Lori; Borer, Elizabeth; Catford, Jane A.; Cleland, Elsa; Hagenah, Nicole; Haider, Sylvia; Harpole, W. Stanley; Komatsu, Kimberly; MacDougall, Andrew S.; Roemermann, Christine; Seabloom, Eric W.; Knapp, Sonja; Kuehn, Ingolf
AIMS : The community composition of native and alien plant species is influenced by the environment (e.g., nutrient addition and changes in temperature or precipitation). A key objective of our study is to understand how differences in the traits of alien and native species vary across diverse environmental conditions. For example, the study examines how changes in nutrient availability affect community composition and functional traits, such as specific leaf area and plant height. Additionally, it seeks to assess the vulnerability of high-nutrient environments, such as grasslands, to alien species colonization and the potential for alien species to surpass natives in abundance. Finally, the study explores how climatic factors, including temperature and precipitation, modulate the relationship between traits and environmental conditions, shaping species success. LOCATION : In our study, we used data from a globally distributed experiment manipulating nutrient supplies in grasslands worldwide (NutNet). METHODS : We investigate how temporal shifts in the abundance of native and alien species are influenced by species-specific functional traits, including specific leaf area (SLA) and leaf nutrient concentrations, as well as by environmental conditions such as climate and nutrient treatments, across 17 study sites. Mixed-effects models were used to assess these relationships. RESULTS : Alien and native species increasing in their abundance did not differ in their leaf traits. We found significantly lower specific leaf area (SLA) with an increase in mean annual temperature and lower leaf Potassium with mean annual precipitation. For trait–environment relationships, when compared to native species, successful aliens exhibited an increase in leaf Phosphorus and a decrease in leaf Potassium with an increase in mean annual precipitation. Finally, aliens' SLA decreased in plots with higher mean annual temperatures. CONCLUSIONS: Therefore, studying the relationship between environment and functional traits may portray grasslands' dynamics better than focusing exclusively on traits of successful species, per se.
Temporal dynamics of scout release-behavior of termitophagous ponerine ant, Megaponera analis
(Springer, 2024-11-05) Modiba, Rifilwe V.; Pirk, Christian Walter Werner; Yusuf, Abdullahi Ahmed
Megaponera analis is an obligate termitophagous species endemic to sub-Saharan Africa. The species forages by sending out scouts to search for termites. Once termites are located, the scouts return to the nest and recruit nest mates. Scouts face unpredictable environmental conditions, including sudden flooding, temperature changes, high winds and predation by natural enemies. We observed 519 scouting trips from 18 different colonies over three years to determine how long it takes for the colony to replace a scout that has likely died while on scouting duty or is lost due to environmental perturbations. Study areas were at Maremani, Musina, Masebe and D’nyala Nature Reserves in the Limpopo Province of South Africa. We introduced definitions of scouting turnover, scouting trip, and scouting session. Scouting turnover is the time it takes a successive scout to leave the nest for a trip, whereas a scouting trip is the journey a scout takes from the nest in search of food. Since M. analis shows bimodal foraging behavior, the morning observations were recorded as the first scouting session, while the subsequent session, which starts in the afternoon, was recorded as the second scouting session. The mean scouting turnover for all 519 trips was 9.36 ± 0.64 (SD) minutes. When turnover was divided into sessions, the first scouting session lasted a mean of 7.77 ± 12.17 (SD) minutes, while the second had 10.34 ± 18.32 (SD) minutes. The minimum turnover was zero minutes, and the maximum was 124 minutes.
The effects of diet and semiochemical exposure on male Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) metabolic rate at a range of temperatures
(Elsevier, 2024-12) Dacre, Dylan Christopher; Duncan, Frances D.; Weldon, Christopher William; cwweldon@zoology.up.ac.za
The oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), is an invasive species that has rapidly spread across the African continent, endangering the security of agricultural industries. The sterile insect technique (SIT) is being investigated as a viable additional pest management tool to suppress B. dorsalis populations after its successful implementation in other parts of the world. There is evidence to suggest that pre-release nutritional and semiochemical treatments for sterilised males can enhance their competitive performance against wild type males in SIT programs. This study examined how sterilisation, a diet rich in protein (addition of yeast hydrolysate) or containing semiochemicals (methyl eugenol or eugenol) affected the resting metabolic (RMR) of male B. dorsalis at different temperatures (15 – 30 ◦C), measured using flow-through respirometry. Our results indicated that the negative effect of sterilisation on RMR decreased as temperature increased and that duration of exposure to semiochemicals for 1 to 4 days was not a significant influencing factor on male B. dorsalis RMR. Protein-rich diet increased average RMR, but the difference in RMR between dietary groups decreased as temperature increased. Semiochemical feeding reduced the average RMR in male B. dorsalis. The difference in RMR between males that consumed semiochemical and those that did not increased with as temperature increased.
From parachuting to partnership : fostering collaborative research in protected areas
(Wiley, 2025-01) Smit, Izak P.J.; Fernández, R.J.; Menvielle, M.F.; Roux, D.J.; Singh, N.; Mabuza, S.; Mthombeni, B.M.; Macgregor, N.A.; Fritz, H.; Gandiwa, E.; Foxcroft, L.C.; Cook, C.N.
Research in protected areas (PAs) is often dominated by scientists from outside the conservation agencies managing them. This can potentially lead to misalignment with local needs, insensitivity to the local context and a lack of investment in and use of local expertise. These issues often arise when international researchers work in another country without local engagement (known as ‘parachute science’). Despite PAs being key end users of actionable science, there is limited understanding of the prevalence and impact of parachute science in these areas. Here, we investigate parachute versus collaborative research in two national parks in the Global South (Kruger National Park, South Africa; Nahuel Huapi National Park, Argentina) and one park from a developed economy (Kakadu National Park, Australia). To explore the prevalence, risks, benefits and complexities of research practices, we analyse the patterns of authorship, funding and acknowledgement in a random sample of peer-reviewed papers from research conducted in these parks. Our findings show a higher incidence of potential parachute science in Kruger National Park (18% of papers with only out-of-country authors) compared to Nahuel Huapi (4%) and Kakadu (2%) national parks. However, the occurrence of internationally collaborative research (national and international authors) was double in Global South parks (35%–38%) than in the Australian park (18%). The study illustrates the potential benefits of international collaboration for PAs, including increased research productivity, expanded funding sources and possibly higher impact and visibility of published studies. PAs in developed countries may have fewer opportunities to obtain those benefits. Most papers, even those with in-country authors, lacked authors affiliated with the agency managing the PA and often failed to even acknowledge these agencies. This suggests the potential for a different form of parachute science (which we term ‘park parachuting’) in which lack of local involvement may hamper integration of research with management. SYNTHESIS AND APPLICATIONS : Establishing conditions that foster collaboration between national and international researchers, and between PA agency staff and external researchers (regardless of their nationality), would enable parks to better serve as catalysts for research collaboration. This collaborative approach can facilitate access to additional funding, enhance research capacity, increase research productivity and amplify research impact.
Using indicators to assess the status of biological invasions and their management on islands─the Prince Edward Islands, South Africa as an example
(Springer, 2025-03) Fernandez Winzer, Laura; Greve, Michelle; Le Roux, Peter Christiaan; Faulkner, Katelyn T.; Wilson, John R.U.
Addressing the challenge biological invasions pose to island biodiversity is pivotal to achieving Target 6 of the Kunming–Montreal Global Biodiversity Framework. Using a suite of 24 indicators, we evaluated the current status of biological invasions and their management on the Prince Edward Islands, South Africa’s sub-Antarctic territories, and provide recommendations for management. There are 45 established alien taxa on Marion Island, of which 25 are invasive, and nine invasive taxa on the less frequently visited Prince Edward Island. However, despite stringent biosecurity, new alien taxa continue to arrive, potentially through ten introduction pathways, but particularly as contaminants on goods and stowaways on transport vectors. Not all detected taxa have been systematically recorded or identified—identifying incursions to species level may help pinpoint gaps in biosecurity. Three invasive plant species have caused Major environmental impacts (as per the Environmental Impact Classification for Alien Taxa categories), and Massive impacts have been recorded for the house mouse. An ambitious plan to eradicate the house mouse is being developed. A further eight taxa are controlled and four monitored to determine whether they have been eradicated. We argue that systematically tracking and documenting biological invasions is vital to improve the appropriateness, adaptability, and responsiveness of management; and we recommend a dedicated, integrated reporting process involving all stakeholders. Such monitoring is particularly important for remote sites given competing demands to reduce the human footprint, manage biological invasions, and allow access. This article is part of the theme issue ‘Managing biological invasions in protected areas: moving towards the new Global Biodiversity Framework targets’.
Sleep in the East African root rat, Tachyoryctes splendens
(Wiley, 2024-12) Kruger, Jean‐Leigh; Bhagwandin, Adhil; Katandukila, Jestina V.; Bennett, Nigel C.; Manger, Paul R.
The present study reports the results of an electrophysiological analysis of sleep in the East African root rat, Tachyoryctes splendens, belonging to the rodent subfamily Spalacinae. Telemetric electroencephalographic (EEG) and electromyographic recordings, with associated video recording, on three root rats over a continuous 72 h period (12 h light/12 h dark cycle) were analyzed. The analysis revealed that the East African root rat has a total sleep time (TST) of 8.9 h per day. Despite this relatively short total sleep time in comparison to fossorial rodents, nonrapid eye movement (non‐REM) sleep and rapid eye movement (REM) sleep states showed similar physiological signatures to that observed in other rodents and no unusual sleep states were observed. REM occupied 19.7% of TST, which is within the range observed in other rodents. The root rats were extremely active during the dark period, and appeared to spend much of the light period in quiet wake while maintaining vigilance (as determined from both EEG recordings and behavioral observation). These recordings were made under normocapnic environmental conditions, which contrasts with the hypercapnic environment of their natural burrows.
Expression of honey bee (Apis mellifera) sterol homeostasis genes in food jelly producing glands of workers
(Wiley, 2024-06) Yusuf, Abdullahi Ahmed; Pirk, Christian Walter Werner; Buttstedt, Anja
Adult workers of Western honey bees (Apis mellifera L.) acquire sterols from their pollen diet. These food sterols are transported by the hemolymph to peripheral tissues such as the mandibular and the hypopharyngeal glands in the worker bees' heads that secrete food jelly which is fed to developing larvae. As sterols are obligatory components of biological membranes and essential precursors for molting hormone synthesis in insects, they are indispensable to normal larval development. Thus, the study of sterol delivery to larvae is important for a full understanding of honey bee larval nutrition and development. Whereas hypopharyngeal glands only require sterols for their membrane integrity, mandibular glands add sterols, primarily 24‐methylenecholesterol, to its secretion. For this, sterols must be transported through the glandular epithelial cells. We have analyzed for the first time in A. mellifera the expression of genes which are involved in intracellular movement of sterols. Mandibular and hypopharyngeal glands were dissected from newly emerged bees, 6‐day‐old nurse bees that feed larvae and 26‐day‐old forager bees. The expression of seven genes involved in intracellular sterol metabolism was measured with quantitative real‐time PCR. Relative transcript abundance of sterol metabolism genes was significantly influenced by the age of workers and specific genes but not by gland type. Newly emerged bees had significantly more transcripts for six out of seven genes than older bees indicating that the bulk of the proteins needed for sterol metabolism are produced directly after emergence.
Light sensitivity of the circadian system in the social highveld mole-rat Cryptomys hottentotus pretoriae
(Company of Biologists, 2024-09) Chanel, Pauline N.C.; Bennett, Nigel C.; Oosthuizen, Maria Kathleen
Highveld mole-rats (Cryptomys hottentotus pretoriae) are social rodents that inhabit networks of subterranean tunnels. In their natural environment, they are rarely exposed to light, and consequently their visual systems have regressed over evolutionary time. However, in the laboratory they display nocturnal activity, suggesting that they are sensitive to changes in ambient illumination. We examined the robustness of the Highveld mole-rat circadian system by assessing its locomotor activity under decreasing light intensities. Mole-rats were subjected to seven consecutive light cycles commencing with a control cycle (overhead fluorescent lighting at 150 lx), followed by decreasing LED lighting (500, 300, 100, 10 and 1 lx) on a 12 h light:12 h dark (L:D) photoperiod and finally a constant darkness (DD) cycle. Mole-rats displayed nocturnal activity under the whole range of experimental lighting conditions, with a distinct spike in activity at the end of the dark phase in all cycles. The mole-rats were least active during the control cycle under fluorescent light, locomotor activity increased steadily with decreasing LED light intensities, and the highest activity was exhibited when the light was completely removed. In constant darkness, mole-rats displayed free-running rhythms with periods (τ) ranging from 23.77 to 24.38 h, but was overall very close to 24 h at 24.07 h. Our findings confirm that the Highveld mole-rat has a higher threshold for light compared with aboveground dwelling rodents, which is congruent with previous neurological findings, and has implications for behavioural rhythms.
Evolutionary shifts in the thermal biology of a subterranean mammal : the effect of habitat aridity
(Company of Biologists, 2024-12) Merchant, Hana N.; Hart, Daniel William; Bennett, Nigel C.; Janse van Vuuren, Andries Koch; Freeman, Marc Trevor; McKechnie, Andrew E.; Faulkes, Chris G.; Mordaunt, Nathan D.; Portugal, Steven J.
Subterranean mammals representing a single subspecies occurring along an aridity gradient provide an appropriate model for investigating adaptive variation in thermal physiology with varying levels of precipitation and air temperature. This study examined the thermal physiological adaptations of common mole-rats (Cryptomys hottentotus hottentotus) across five populations along an aridity gradient, challenging the expectation that increased aridity would lead to reduced metabolic rate, lower body temperatures and broader thermoneutral zones. No significant, consistent differences in metabolic rate, body temperature or thermal conductance were observed between populations, suggesting uniform thermoregulatory mechanisms across habitats. Instead, behavioural strategies such as huddling and torpor may play a more prominent role than physiological adaptations in managing temperature regulation and water balance. The study also observed osmoregulatory differences, with populations employing distinct behavioural cooling strategies in response to water availability. These results underscore the need for further research into the responses of subterranean species to climate change, particularly in understanding how increasing global temperatures and aridification might influence species distribution if they lack the physiological capacity to adapt to future climatic conditions.
Contest competition and injury in adult male sub-Antarctic fur seals
(Springer, 2024-05) Bester, Marthan Nieuwoudt; Rossouw, G.J.; Van Staden, Paul Jacobus; mnbester@zoology.up.ac.za
We recorded intra-sexual behaviour of adult male sub-Antarctic fur seals Arctocephalus tropicalis at Gough Island, Southern Ocean, during the 1975/76 summer breeding season. Our re-analysed data address male ‘contest competition’, which relates to the costs of intra-sexual disputes, including fights. We considered the risks/benefits of fighting through investigation of injuries (n = 353) sustained by adult males (n = 124) in fights. Injuries were predominantly on the forequarters, especially around the insertion areas of the front flippers (41%) with its sparse pelage, compared to the neck and chest areas combined (29%), an area which is well protected by thick pelage. The infliction of serious, sometimes debilitating, injuries to competitors increases a male’s access to females. Injuries predominate in injured, defeated males that gather at non-breeding sites, suggesting that injuries inflicted by dominant males were successful in excluding competing males from breeding sites.

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