Research Articles (Mammal Research Institute)

Permanent URI for this collectionhttp://hdl.handle.net/2263/5233

A collection containing some of the full text peer-reviewed/ refereed articles published by researchers from the Mammal Research Institute

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Does the public value ecosystem services secured by pine savanna restoration and bobwhite management on private lands?
Nimlos, Nicole M.; Pienaar, Elizabeth Frances; Martin, James A. (Elsevier, 2026-03)
Private land stewardship in the southeastern United States is crucial to attain pine savanna restoration and conservation of the threatened northern bobwhite (Colinus virginianus). Both government and privately funded conservation efforts secure numerous ecosystem services, including groundwater recharge, scenic open spaces, and biodiversity. Yet, we have incomplete information on whether the public values these ecosystem services. From June 15th to July 19th, 2022, we administered stated preference choice experiment surveys to 770 members of the public in Alabama, Georgia, Florida, and South Carolina to ascertain if the public values ecosystem services provided by pine savanna and bobwhite conservation. We analyzed data using hybrid mixed logit models. Respondents positively valued recovery of threatened bobwhite and gopher tortoise populations and high levels of groundwater recharge and scenic open space. Respondents with higher moral obligations to prevent land use conversion (personal norms, awareness of consequences, and ascription of responsibility related to conservation) were more likely to support allocation of taxes to pine savanna restoration on private lands. Respondents' moral obligation to prevent land use conversion was positively correlated with their engagement in outdoor recreational activities. Our findings indicate that the public values pine savanna and bobwhite conservation efforts on private lands in the Southeast, and that outreach related to pine savanna restoration efforts should appeal to people's moral obligation to support conservation of biodiversity, habitat restoration, and the provision of ecosystem services. HIGHLIGHTS • We use hybrid mixed logit models to analyze preferences for pine savanna restoration. • Moral obligation to prevent land use conversion depends on political orientation. • Recreational activities and moral obligation influence support for restoration programs. • Respondents placed greatest value on bobwhite recovery and high groundwater recharge.
Comparing seismic survey mitigation regulations : lessons for South Africa from international frameworks
Purdon, Jean; Somers, Michael J.; Shabangu, Fannie Welcome; Doh, Y.; Scheun, J. (Taylor and Francis, 2025-11-24)
Underwater seismic surveys generate high-intensity, low-frequency noise that can negatively affect a range of marine fauna. As a result, countries have implemented mitigation regulations to reduce the potential impacts of this activity. This study examines seismic survey mitigation regulations from Australia, the United States, Brazil, New Zealand, Canada and the United Kingdom, and compares them with the current regulations in South Africa. We focused on setting the radii of exclusion zones, ‘soft-start’ procedures, passive acoustic monitoring, marine mammal observer qualifications and standards, and regulatory oversight. Of the six countries reviewed, Australia and New Zealand have implemented the most robust mitigation measures. Furthermore, Australia stands out for its independent regulatory authority overseeing offshore environmental compliance. We recommend the establishment of an independent regulatory board in South Africa to oversee the development of environmental impact assessment guidelines and mitigation protocols. By adopting these measures and aligning with international best practice, South Africa could become a regional, if not global, leader in science-based environmental regulation and the protection of marine fauna from seismic surveys.
Exported illegally, threatened locally : South Africa in the global reptile pet trade
Willoughby, Sian; Selier, SA Jeanetta; Zondi, Zwelakhe; Hall, Grant (Taylor and Francis, 2025)
The global illegal exotic pet trade is a major driver of biodiversity loss, particularly affecting reptile species listed under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix II. CITES is an international agreement used to monitor the import and export of listed fauna and flora, ensuring trade is not detrimental to the survival of listed species in the wild. This study investigates South Africa’s role in the international trade of reptiles, using the endemic Sungazer lizard (Smaug giganteus) as a case study. Analysis of CITES Trade Database records reveals systemic reporting in accuracies, including discrepancies between importer and exporter data, misuse of source and purpose codes, and evidence of wildlife laundering. Trade peaks in 1988 and 2013 correspond to increased species visibility due to CITES listing and cultural associations with popular media, respectively, illustrating the influence of anthropogenic and media-driven factors on global wildlife trade demand. Evidence of potentially illegal exports from non-range countries and suspicious declarations of captive-bred specimens suggests that South Africa may be both a source and transit country in illicit reptile trade networks. The lack of enforcement, coupled with the ease of smuggling, exacerbates the threat to S. giganteus and similar threatened reptile species. These findings underscore the urgent need to strengthen CITES data reliability, enforce trade regulations, and enhance protection for South African reptile species vulnerable to overexploitation.
Intensive feeding modifies nutrient patterns in a strictly protected area
Trepel, Jonas; Abraham, Andrew J.; Di Nicola, Walter; Gelin, Uriel; Gahbauer, Martin; Heurich, Marco; Le Roux, Elizabeth (Elsevier, 2025-09)
Recovering deer populations are causing conflict across Europe, especially in the vicinity of protected areas where densities are generally higher. Consequently, a variety of management approaches, such as the provision of winter feeding, have been deployed to keep deer from foraging in undesired areas in an attempt to mitigate conflicts. However, as large ungulates play a key role in nutrient recycling and redistribution, management actions that affect their space use and introduce additional nutrients into a system may translate into changes in the biogeochemistry of protected areas. Yet, little is known about the implications of such deer-management strategies on nutrient patterns. Here, we tested the effects of intensive supplementary feeding in combination with winter enclosures on nutrient distribution in a strictly protected area in Central Europe, the Bavarian Forest National Park. We found significant effects of the current management approach on plant nutrients with elevated nutrient concentrations not only within, but, importantly, extending up to several hundred meters around the enclosures/feeding stations. The increased nutrient concentrations could have cascading consequences for soil microbial activity, plant community composition and other herbivores. Our results illustrate that management actions designed to solve a specific problem (mitigating human-wildlife conflict), may alter local landscape chemistry and influence broader ecosystem functions. Ultimately, this may compromise conservation success, highlighting the need to critically evaluate all potential consequences of common management approaches such as supplementary feeding.
Perspectives on wildlife agency mange management in black bears and other carnivores
Francisco, Raquel; Pienaar, Elizabeth Frances; Yabsley, Michael J. (Wiley, 2026-02)
Sarcoptic mange is an emerging parasitic disease affecting North American black bears (Ursus americanus) and has been increasingly reported since the early 1990s. As mange spreads into naive bear populations, wildlife managers face challenges related to surveillance, interagency coordination, and stakeholder expectations. In 2023, we surveyed 35 state and federal wildlife agency personnel and academic partners to assess management practices for mange, barriers to effective interventions, and how agencies engage with the public and key stakeholders. Respondents represented 17 states, 7 with and 10 without reports of sarcoptic mange in black bears, with over half (51.4%) working in their current institution for more than 10 years. Respondents generally agreed on dispatching severely affected wildlife (97.1%) and monitoring mild to moderate cases. Although respondents supported stakeholder and public reporting of mange cases (71.4%), they opposed stakeholder and public intervention in mange management (e.g., treatment, handling, relocation). Fewer than half of respondents (45.7%) indicated that mange reports are entered into a formal dataset, limiting long-term surveillance and decision-making. Our study highlights the need for a unified multi-state communication framework to increase public support for agency management actions, and the importance of implementing a centralized mange data repository to enhance long-term surveillance of mange and improve response efforts.
Biomass distribution of sympatric mammals in a European temperate forest
Pleskalt, Andro; Farias, Sebastião; Vicedo, Toni; Álvarez-Martínez, Jose Manuel; Roces-Díaz, José Valentín; Meloro, Carlo; Pereira, Soraia; Cruz, Antonio; García, Jesús; Gómez, Pablo; Lamillar, María Ángel; Marsella, Elena; Varas, Manuel Jesús; Álvarez, Elena; Dalerum, Fredrik (The Royal Society, 2025-08)
The distribution of biomass among trophic levels and different types of organisms is a key characteristic of ecosystems. However, such biomass distributions might exhibit large perturbations owing to human activities. We used long-term camera trap data from a temperate forest ecosystem within the Cantabrian range, northern Spain, to quantify the biomass distribution of 10 mammal species ranging in body mass from 300 g to almost 100 kg. The species are representative of three distinct orders and include trophic levels from primary to secondary consumers. The observed biomass distribution was bottom-heavy with a disproportionally low biomass of secondary consumers, in particular large-bodied predators. In addition, the ratio of plant biomass to the biomass of mammalian primary consumers was over 6000 : 1 for total above-ground-plant biomass and over 700 : 1 for plant biomass available for mammal consumption. We suggest that the observed biomass distribution both among mammals and between mammals and plants provide an example of trophic downgrading, and highlight the radical effects human activities might have on the structure of terrestrial ecosystems.
Four decades of annual monitoring reveal declining reproductive success of a migratory baleen whale
Vermeulen, Els; Wilkinson, Christopher; Best, Peter B.; Findlay, Kenneth Pierce (Nature Research, 2025-10-06)
Understanding and mitigating threats to species survival relies on the ability to track key demographic processes over time. Among these processes, reproduction stands out as a primary biological driver of population growth and resilience. Multiple factors affect reproductive success, including environmental variables and resource availability. Long-term trends in reproductive parameters of long-lived species can thus serve as indicators of ecosystem health over meaningful timescales. This study analyses the reproductive performance of southern right whales (Eubalaena australis) in South Africa using forty years of individual sighting histories. Results reveal that the median and average calving intervals increased post-2010, reaching an average maximum of 7.2 years in 2022. The average calving rate decreased significantly across the four decades, from 0.48 calves/year in the 1980s to 0.19 calves/year in the 2010s. Although based on observational data, these findings align with the hypothesis of a trade-off linked to the reduced maternal body condition in this population, likely indicative of diminished foraging success associated with recorded regional Antarctic sea ice declines and reduced prey availability. The study adds to the growing evidence that baleen whale reproduction is influenced by environmental change, reinforcing the need for long-term monitoring to understand population dynamics and their potential role as sentinels of ocean health.
Territoriality in adult male sub-Antarctic fur seals at Gough Island
Bester, Marthan Nieuwoudt; Rossouw, G.J. (Springer, 2025-03)
We analysed unpublished data on territory size and tenure in adult male sub-Antarctic fur seals Arctocephalus tropicalis recorded at Gough Island, Southern Ocean, during the 1975/76 austral summer breeding season. Adult males (n=15) remained on their territories for between 35–56 days (mean 45.4±6.7 days). Territory size during the peak breeding season was 21.9 m2 on average (n=42), but when partitioned by beach type, average territory sizes were 13.8 (n=9), 20.1 (n=17) and 28.3 m2 (n=16). Both territory tenure and territory size fall within the reported range of values established in fur seal species which hold territories on land as the predominant male reproductive strategy. We highlight numerous confounding factors that impact comparative studies which should be considered when interpreting theoretical, conceptual, and modelling approaches about territorial behaviour in otariids.
Seasonal occurrence and condition of leopard seals at an extralimital Sub‑Antarctic Island
Ross, Michael D.; Leitner, Monica; Oosthuizen, W. Chris; Bester, Marthan Nieuwoudt; Jordaan, Rowan Keith; Voysey, Michael D.; Conradie, Everhard C.; Dosi, Banele; Evans, Sean; Lloyd, Kyle J.; Monier, Zafar; Purdon, Jean; Reisinger, Ryan R.; Shihlomule, Yinhla Desmond; Van der Vyver, J.S. Fredrik; De Bruyn, P.J. Nico (Springer, 2025-06)
Leopard seals (Hydrurga leptonyx) occur mainly south of the Antarctic Polar Front, but immatures, in particular, seasonally move beyond this range during the austral winter and spring, typically under increased sea ice conditions. Extralimital occurrences of leopard seals can be observed at several sub-Antarctic islands where they haul out to rest. We present new records of leopard seal sightings at Marion Island, southern Indian Ocean, from 2006 to 2024 and discuss fluctuations in their seasonal and annual abundance (drawing on data collected since 1980) and body condition based on regular surveys. The eastern beaches at Marion Island were surveyed every 7–10 days while the western beaches were visited monthly. Observed leopard seals were photographed and given a body condition score based on the visibility of bony protrusions. From 2006 to 2024, we identified 35 presumed unique immature leopard seals between July and November, with a peak in September, all being immatures. Individuals to which we could assign body condition scores were either in good or excellent condition. This contrasted with the prevailing hypothesis that leopard seal body condition deteriorates with decreasing latitude. However, we could not determine whether this was because of an actual shift in body condition or because we used a different scoring system from other studies. We recommend adopting a standardised scoring system for visually estimating pinniped body condition and a global repository to monitor leopard seal haul-outs. As an apex predator, leopard seals may be important indicators in Antarctic and sub-Antarctic ecosystems, and monitoring changes in their distribution and body condition may indicate environmental and biological changes in these remote regions.
Monitoring of vagrant seals on mid-oceanic islands of the South Atlantic Ocean
Bester, Marthan Nieuwoudt; Somers, Michael J. (Springer, 2025-09)
Extra-limital sightings of seals breeding on the Antarctic pack- and fast ice and on sub-Antarctic and temperate islands of the South Atlantic Ocean are summarised. Particular life history events of four vagrant seal species that have turned up on Mid-Atlantic Ridge islands are presented, and the likely arrival of a further three vagrant seal species is speculated upon. The setting up and/or expansion of a recording system underpinned by an appropriate sighting protocol for vagrant seals in which citizen scientists can participate is advanced. Determination of whether range contractions/expansions of seals in the South Atlantic are taking place reflects on the status of the source population(s). Seal vagrancy may conceivably also be involved in the spread of viral diseases such as highly pathogenic avian influenza and rabies. Insights gained through extra-limital sightings of seals may assist with the establishment of conservation strategies.
Comparative life-cycle analyses reveal interacting climatic and biotic drivers of population responses to climate change
Ickin, Esin; Conquet, Eva; Abrahms, Briana; Albon , Steve D.; Blumstein, Daniel T.; Bond, Monica L.; Boersma , P. Dee; Clark-Wolf, Tyler J.; Clutton-Brock, Tim H.; Compagnoni , ldo; Dostálek, Tomáš; Evers, Sanne M.; Fichtel, Claudia; Gamelon, Marlène; García-Callejas, David; Griesser, Michael; Hansen , Brage B.; Jenouvrier, Stéphanie; Jerstadz, Kurt; Kappeler, Peter M.; Layton-Matthews, Kate; Lee, Derek E.; Lloret, Francisco; Loonen, Maarten J.J.E.; Malchow, Anne-Kathleen; Manser, Marta B.; Martin , Julien G.A.; Morales-González, Ana; Münzbergová, Zuzana; Nater, Chloé R.; Pillay, Neville; Quéroué, Maud; Røstadak, ac,ad, ai,al, am, a and , Ole W.; Sánchez-Mejía, Teresa; Schradin, Carsten; Sæther, Bernt-Erik; Ozgul, Arpat; Paniw, Maria (Oxford University Press, 2025-09)
Responses of natural populations to climate change are driven by how multiple climatic and biotic factors affect survival and reproduction, and ultimately shape population dynamics. Yet, despite substantial progress in synthesizing the sensitivity of populations to climatic variation, comparative studies still overlook such complex interactions among drivers that generate variation in population-level metrics. Here, we use a common framework to synthesize how the joint effects of climate and biotic drivers on different vital rates impact population change, using unique long-term data from 41 species, ranging from trees to primates. We show that simultaneous effects of multiple climatic drivers exacerbate population responses to climate change, especially for fast-lived species. However, accounting for density feedbacks under climate variation buffers the effects of climate change on population dynamics. In all species considered in our analyses, such interactions between climate and density had starkly different effects depending on the age, size, or life-cycle stage of individuals, regardless of the life history of species. Our work provides the first general framework to assess how covarying effects of climate and density across a wide range of population models can impact populations of plants and animals under climate change.
Development of an 11-oxoetiocholanolone mini-kit for the quantification of faecal glucocorticoid metabolites in various wildlife species
Edwards, KatieL.; Wheaton, Catharine J.; Brown, Janine L.; Dimovski, Alicia M.; Fanson, Kerry V.; Ganswindt, Andre; Ganswindt, Stefanie Birgit; Hagenah, Nicole; Keeley6, Tamara; Möstl, Erich; O’Hara, Bobbi; Penfold, LindaM.; Shablin, Samantha A.; Palme, Rupert (Oxford University Press, 2025-10)
As part of its mission to advance the field of wildlife endocrinology, the International Society of Wildlife Endocrinology aims to develop cost-effective antibodies and enzyme immunoassay kits that support research across a diverse range of species and sample matrices. To provide additional options for the quantification of faecal glucocorticoid metabolites (fGCMs), an antibody against 11-oxoetiocholanolone-17-carboxymethyl oxime (CMO) was generated in rabbits, and an enzyme immunoassay incorporating a horseradish peroxidase-conjugated label and 11-oxoetiocholanolone standard has been developed, designed for use with anti-rabbit IgG secondary antibody coated plates. This mini-kit was used to quantify glucocorticoid metabolites with a 5β-3α-ol-11-one structure in faecal extracts from 23 species: African and Asian elephants, Alpine chamois, American bison, Bengal tiger, blue wildebeest, blue-and-yellow macaw, brushtail possum, cape buffalo, fat-tailed dunnart, Florida manatee, ghost bat, giraffe, golden langur, Gould’s wattled bat, hippopotamus, Leadbeater’s possum, mandrill, okapi, roan antelope, samango monkey, short-beaked echidna, and western lowland gorilla. Pharmacological (adrenocorticotropic hormone challenge) and biological (inter-zoo translocation, wild capture, social disruption, illness/injury and veterinary intervention) challenges resulted in expected increases in fGCM concentrations, and in a subset of species, closely paralleled results from a previously established immunoassay against 11-oxoetiocholanolone-17-CMO. Two additional species tested, Krefft’s glider, which showed contradictory results on this assay compared to a previously validated enzyme immunoassay (EIA) and Ankole cow, where the magnitude increase post-event did not quite reach the 2-fold change criteria, highlight that differences in excreted faecal metabolites across species mean that no EIA will be suitable for all species. This assay provides a valuable new option for assessing adrenal activity across taxa using a group-specific antibody. Future studies should put similar emphasis on validation to determine optimal assay choice for measuring fGCMs in a variety of species.
Staying alive : individual behavioral variation influences survival, but not reproductive success, in female group-living ground squirrels
Warrington, Miyako H.; Van der Marel, Annemarie; Sojka, Jennifer; Shofstall, Krista J.; Waterman, Jane M. (Wiley, 2025-07)
Animals living in harsh or unpredictable environments adopt adaptive strategies to improve their fitness, with behavioral variation playing a key role in shaping individual outcomes. We examined whether between-individual variation in behavioral traits (personality) was associated with reproductive success and survival in female Cape ground squirrels (Xerus inauris). Using a 10-year dataset (2011–2021), we quantified behavioral expressions of the animal's response to trapping and handling (trap response, as a proxy for docility), trapping rate (trappability, for boldness) and the number of different trapping locations an animal was trapped at (trap diversity, for exploration) and examined their associations with (1) annual reproductive success, (2) lifetime reproductive success, (3) annual survival, and (4) on-site persistence (a proxy for lifespan). Response measures taken during transfer from the cage, handling by a human observer, and whether individuals ran or walked after release were moderately repeatable. Trappability was also repeatable, while trap diversity was not. Trap response and trappability were positively correlated with survival, but not reproductive success. Females that easily transferred from the trap to the handling bag (more docile) had higher annual survival, while those that ran after release had longer lifespans. Individuals trapped at a higher rate (bolder) had higher annual survival. The absence of a relationship between behavioral traits and reproductive success in females suggests that other factors, such as group dynamics, social interactions, and maternal effects, may be more influential in explaining the high reproductive skew in female reproductive success. Overall, our findings highlight the role of individual behavioral variation in shaping survival outcomes while emphasizing the need for further research into the mechanisms driving reproductive success in this species.
Multiyear Baleen endocrine profiles suggest a longer estimated gestation in southern right whales (Eubalaena australis)
Shuttleworth, Loraine; Ganswindt, Andre; Hunt, Kathleen E.; Fernandez Ajo, Alejandro; Pieterse, Estefan; Seakamela, S. Mduduzi; Schoeman, Chantel; Vermeulen, Els (Wiley, 2025-06)
Gestation length is a key reproductive parameter influencing fecundity, population growth rates, and the recovery potential of baleen whales. However, direct knowledge of the gestation length in these large mammals remains limited, primarily inferred from whaling and observational data. Over the past decade, southern right whales have experienced a decline in reproductive success, likely linked to climate-change-induced shifts in foraging conditions. Understanding the population-level consequences of these changes requires detailed longitudinal reproductive data. This study analyzes multiyear steroid hormone profiles in the baleen of adult female southern right whales stranded along the South African coast. Results show an extended hormonal pattern characterized by two peaks in progestogens between 20 and 25 months—suggesting putative pregnancies lasting substantially longer than previous estimates. Sharp estrogen peaks during periods of elevated progestogen phases may indicate hormonal regulation of myometrial contractions at birth. A positive correlation between progestogens and glucocorticoids suggests a role for glucocorticoids in pregnancy maintenance, while androgens provide limited insight into female reproduction in this species. These findings imply a longer-than-expected gestation period for southern right whales and potentially across the balaenid family. This has important implications for understanding the timing and location of conception, relevant for conservation management strategies. Multipopulation studies alongside individual sighting histories are recommended to refine our understanding of southern right whale reproduction further.
Monthly and diel acoustic occurrence of four Baleen whale species in South African waters
Shabangu, Fannie Welcome; Hlati, Kuhle; Van den Berg, Marcel A.; Lamont, Tarron; Kirkman, Stephen P. (Wiley, 2025-08)
Understanding of the spatio-temporal occurrence of cetaceans post the whaling era is essential for protecting and improving management strategies of these marine mammals. To determine the monthly and diel acoustic occurrence of four baleen whale species relative to environmental conditions off the west coast of South Africa, we collected passive acoustic monitoring data within Child's Bank marine protected area in January and May through October 2024 at various water depths. Burst tonal calls of the southern African Bryde's whale offshore population were detected in January and May through July with the highest occurrence in January. Humpback whale songs and southern right whale gunshot sounds were detected from May through October with high occurrence in September and with smaller modes in other months. Antarctic minke whale bioduck calls were also found in June through October, showing high occurrence in August through October. Calls from an unknown source with similar characteristics to Antarctic minke whale bioduck calls were present in May, July, and August with the highest occurrence in August. Diel acoustic occurrence of Bryde's, southern right, Antarctic minke, and minke-like whale calls indicated that these animals vocalised more during the day while humpback whales were more vocally active at night. Sea surface height and sea surface temperature, either separately or in combination, were the most important predictors of whale acoustic occurrence, highlighting the influence of environmental conditions on the distribution, habitat selection, and ecology of these whales. Overall, this study advances our understanding of the movement, occurrence, and behavioural patterns of several baleen whales relative to environmental conditions. It also provides the first description of the southern African Bryde's whale offshore population's call characteristics, which will be useful at guiding future studies to acoustically differentiate between it and the inshore population.
Interspecies haptic sociality : an observation of grooming between two mongoose species
Smith, Kyle; Hepplewhite, Malcolm; San, Emmanuel Do Linh; Somers, Michael J. (Wiley, 2025-06)
Meerkats (Suricata suricatta) and yellow mongooses (Cynictis penicillata) share many behavioural characteristics and are known to, on rare occasions, live in close association through displayed cooperative vigilance and shared burrow use. Here, we describe the first visual observation of tactile social behaviour through grooming between a meerkat and a yellow mongoose in the Rietvlei Nature Reserve, South Africa. We hypothesise that the close relationship between the two species in the reserve may be a response to a combination of phylogenetic ties, shared behavioural traits, and the population collapse of meerkats in the reserve that exposed a vacant social niche. This observation of interspecific sociality further extends our knowledge of cooperation and group augmentation among meerkats, yellow mongooses and carnivores in general.
Dietary plasticity of African clawless otters (Aonyx capensis) : an assessment of seasonal variation in prey availability
Burger, Marli; Ganswindt, Andre; Majelantle, Tshepiso L.; Scheun, Juan; Webster, Andrea B. (Wiley, 2025-07)
African clawless otters (Aonyx capensis) are opportunistic feeders with a broad dietary niche. Variation in their diet can be influenced by environmental and anthropogenic factors, which can affect seasonal and longitudinal prey availability. Flexibility in the diet allows African clawless otters to adapt to these changes and exploit novel prey items when available. Seasonal examination of otter spraints from three different locations across South Africa demonstrates that African clawless otters are able to shift from their preferred crab-based diet to a fish- or insect-based diet in response to environmental and anthropogenic drivers. Here we provide direct evidence of African clawless otters in terrestrial environments shifting to an insect-dominated diet when this resource is available. The dietary plasticity and response of this species to the shifts in available prey items may be an important factor for future consideration in conservation management of the species.
Stretching out : leopard home-range expansion in response to suppressed population density in a recovering post-war landscape
Briers-Louw, Willem D.; Kendon, Tamar A.; Hayes, Andres; Gaynor, David; Naude, Vincent (Wiley, 2025-10)
Large carnivores have profound regulatory effects on ecosystems and provide substantial socio‐economic benefits. However, mounting anthropogenic pressures are driving their global decline, threatening many species with extinction. Leopards, in particular, face challenges due to their wide‐ranging behavior, which exposes them to conflict with people and bycatch snaring, highlighting the importance of understanding their spatial ecology to develop more effective conservation strategies. This study aimed to estimate the home‐range size of female leopards (n = 4) within the Zambezi Delta, a unique mesic landscape undergoing broad‐scale ecological recovery in central Mozambique. Home‐range sizes ranged from 46 to 365 km2, falling within the range of global estimates. Surprisingly, these home‐range sizes, along with additional parameter estimates such as daily distance moved and home‐range overlap, were most comparable with those reported in arid environments. With female leopards appearing to occupy larger areas than theoretically required based on energetic needs, it is plausible that their spatial ecology is likely influenced by low population density. As the population recovers, we anticipate a re‐structuring of socio‐spatial dynamics driven by dispersal‐regulated processes, with females likely contracting their home‐range and partitioning them to their philopatric daughters. This study provides the first robust estimation of leopard home ranges in Mozambique and provides critical insights into the spatial ecology of leopards in a post‐war landscape. We recommend long‐term monitoring to track changes in population demographics and socio‐spatial dynamics as restoration efforts continue across central Mozambique.
A database on the historical and current occurrences of snakes in Eswatini
Monadjem, Ara; Boycott , Richard C.; Litscha-Koen, Thea; Kane, Adam; Dlamini, Wisdom M.; Mmema, Lindelwa; Strutton, Katharine L.; Hlophe , Zakhele; Padidar, Sara (Oxford University Press, 2025-07)
Snakes are among the most difficult terrestrial vertebrates to survey, resulting in poor distributional information on most species. This database comprises of 3812 records of 58 species of snakes in 37 genera reported from within the boundaries of Eswatini. The data were compiled from multiple sources including museum specimens, iNaturalist records, literature records, and snake rescue operations. For each specimen reported in the database, we provide the scientific name, latitude and longitude coordinates, and location. Most records also have an associated date. This comprehensive database will be useful to biodiversity experts, conservationists, medical practitioners, researchers, and snake enthusiasts, especially for mapping and modelling snake distributions in the country. To allow easy viewing of the distribution of snakes in the country, we provide an online visualization tool, which should allow a greater number of non-scientists to utilize this database.
Short communication: Elevated testosterone correlates with enhanced innate immune function in a cooperatively breeding rodent
Wallace, Kyra Mary Elizabeth; Venter, S.N. (Stephanus Nicolaas); Bennett, Nigel Charles; Hart, Daniel William (Elsevier, 2025-10)
In many vertebrates, elevated testosterone is believed to compromise the immune function, reflecting a trade-off between reproduction and survival. However, such trade-offs may potentially be relaxed in cooperative breeders, where social conflict and sexual selection are reduced. We investigated the relationship between testosterone, cortisol, and innate immunity in captive male Damaraland mole-rats (Fukomys damarensis), a eusocial rodent with minimal aggression-driven reproductive competition. Using microbial killing assays (MKAs) and white blood cell counts as proxies of immune function, we found that urinary testosterone concentration was positively correlated with immune strength. Males with higher urinary testosterone concentrations exhibited significantly greater antimicrobial capacity and elevated total white blood cell counts. However, urinary testosterone was unrelated to independent immune cell differentials. While, reproductive status, age, body mass, and urinary cortisol concentrations had a limited effect on any immune metric. These findings, while correlative, challenge traditional endocrine-immune trade-off models and infer that, in this species, testosterone may signal condition rather than impose immunosuppressive costs.

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