Research Articles (Biodiversity and Conservation Biology)

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A taxonomic revision of the twelve-scaled species of struthiola (thymelaeaceae: thymelaeoideae): the struthiolamundiig roup
(Elsevier, 2025) Boatwright, James; Makhoba, Thuli; Magee, Anthony Richard
Struthiola L. (Thymelaeaceae: Thymelaeoideae) is a genus of approximately 40 species (Wright, 1915; manning and goldblatt, 2012) largely endemic to South Africa, but with four species in tropical Africa (Peterson, 1958, 1978, 2006). the Greater Cape Floristic Region (GCFR) is the centre of diversity for the genus, as well as for several other related southern African Thymelaeoideae, including Gnidial., Lachnaea l. and Passerina l. Almost all of the South African species of Struthiola are restricted to the GCFR (manning and goldblatt, 2012; Snijman, 2013), with only three of the South African species occurring beyond the region in the grasslands of KwaZulu-Natal (Wright, 1915; hilliard and burtt, 1986; Hilliard, 1993). Struthiola l. was established by Linnaeus (1767) in his Systema Naturae ed. 12 for two species of Thymelaeaceae that were characterised by flowers with just four anthers and petaloid scales (incorrectly described as nectary glands) and subsequently conserved against the earlier name Belvala Adans. (1763) with the conserved type S. erecta l. The genus was last revised more than a century ago by Wright (1915), and as the taxonomy of the southern African species remains poorly understood it has been identified as one of the priority groups for taxonomic revision (Victor et al., 2015; Victor, 2020). Meisner (1857), in his global treatment of Thymelaeaceae, subdivided the genus into three morphological groups based on the number of petaloid scales in the mouth of the hypanthium, viz. four, eight or 12. All subsequent authors have retained these informal subdivisions. The molecular analyses by Makhoba (2024) recovered the species with four scales (the Struthiola striata group) and those with 12 scales (the Struthiola mundii group) as two independent clades nested within the remaining species of the genus, all with eight scales. This confirms the value of the putatively derived scale-numbers of four and 12 in identifying relationships in the genus. The four-scaled S. striata group was recently revised (Makhoba et al., 2019) as a first step towards a comprehensive revision of the genus. As the next step we present a revision of the twelve-scaled species comprising the S. mundii group. Twelve species and three varieties were recognized in the S. mundii group at the onset of this study. Characters such as habit, flower colour, presence or absence of hairs on the hypanthium, hypanthium length, shape of the petaloid scales and the colour of the associated hairs, bracteole length, and presence or absence
The first record of Cape Clawless Otters Aonyx capensis predating on African Penguins Spheniscus demersus
(Taylor&Francis, 2025) Snyman, Albert; Ludynia, Katrin; Purves, Arne
The African Penguin Spheniscus demersus, a critically endangered seabird endemic to southern Africa, faces substantial threats from terrestrial predators at its mainland colonies. Correct identification of the predator species is essential for effective conservation management. This study provides the first documented evidence of Cape Clawless Otter Aonyx capensis predation on African Penguins. We describe characteristic lesion patterns distinguishing otter predation from other predators, such as Caracal Caracal caracal. These findings underscore the importance of accurate predator identification to guide targeted mitigation strategies and highlight the need for adaptive management to protect vulnerable mainland African Penguin colonies from emerging predation pressures.
Technical considerations for use of sodium azide in plant biotechnology-assisted genetic improvement
(Springer Science and Business Media Deutschland GmbH, 2025) Naidoo, Sershen; Lozada, Alberto; Gómez, Daviel
odium azide has been used in plant biotechnology as a mutagen to induce genetic variation in plants for the purpose of improving traits such as yield, disease resistance, and stress tolerance, for more than four decades. It acts by causing random mutations and researchers can expose plant seeds and a variety of zygotic and vegetative explants to sodium azide for this purpose. Sodium azide can also be used in combination with other biotechnological tools, such as genetic engineering, to further enhance the genetic improvement of plants; for example, to induce mutations in plants that have been genetically modified to overexpress certain genes. Its sustained use over what has been plant biotechnology’s most intense period of innovation speaks to the value of sodium azide as a tool for creating genetic diversity and facilitating the development of new plant varieties with improved traits. Its widespread application in plant biotechnology has led to a lot of variation across facilities/laboratories and species in terms of the methods of exposure, tissues targeted, concentrations used, mutagenic efficiency and biological consequences. The use of mutagens like sodium azide also raises ethical concerns around the unintended consequences and potential risks of mutagens to the environment and human health. This motivated the current review on the technical considerations for the use of sodium azide in plant biotechnology-assisted genetic improvement. Despite the challenges associated with the use of sodium azide (mainly related to a decline in growth) when the method of application is optimized (in terms of plant material, concentration and exposure method) the technique can be a valuable, low cost, option for developing new plant varieties with improved characteristics that can benefit agriculture and food security. © Plant Science and Biodiversity Centre, Slovak Academy of Sciences (SAS), Institute of Zoology, Slovak Academy of Sciences (SAS), Institute of Molecular Biology, Slovak Academy of Sciences (SAS)
Mass mortality of African Penguins (Spheniscus demersus) caused by Cape honeybees (Apis mellifera capensis)
(Taylor & Francis, 2025) Ludynia, Katrin; Snyman, lbert; Kock, Alison
The African Penguin (Spheniscus demersus) is a seabird endemic to southern Africa and is currently classified as critically endangered, with fewer than 10,000 breeding pairs left in the wild. Sixty-four African Penguins were found dead at a mainland colony in South Africa in September 2021 after being attacked by Cape honeybees (Apis mellifera capensis), a subspecies endemic to the southern coast of South Africa. An additional adult penguin was found alive with red-stained urine and died shortly after rescue. Post-mortem examination revealed bee stingers embedded in featherless facial areas, accompanied by localised erythema and swelling. The number of stingers ranged from 2 to 35 per penguin (on average 3.5 ± 2.7 stingers/kg in adult males and 4.1 ± 3.6 stingers/kg in adult females), suggesting the species may have a low tolerance to bee venom. Internal lesions were consistent with those previously reported in bee envenomation in other birds and mammals, including severe pulmonary congestion and oedema, systemic shock, and acute kidney injury. The cause of the bee attacks remains unclear but may relate to disturbance by humans or penguins. Habitat degradation and proximity to human activity can increase the risk of bee attacks. Management strategies should include buffer zones for beekeeping, removing or relocating highrisk hives, and educating residents about the risks of beekeeping near colonies. Understanding the drivers of bee defensiveness will be important to prevent further incidents and ensure this endemic bee subspecies does not become an added threat to the African Penguin.
Enabling conservation theories of change
(London: Nature Publishing Group UK, 2024) Christina A. Buelow; Anusha Rajkaran
Global theories of change (ToCs), such as the post-2020 global biodiversity framework (GBF), provide broad, overarching guidance for achieving conservation goals. However, broad guidance cannot inform how conservation actions will lead to desired outcomes. We provide a framework for translating a globalscale ToC into focussed, ecosystem-specific ToCs that consider feasibility of actions, as determined by national socioeconomic and political context (i.e., enabling conditions). We demonstrate the framework using coastal wetland ecosystems as a case study. We identified six distinct multinational profiles of enabling conditions (‘enabling profiles’) for coastal wetland conservation. For countries belonging to enabling profiles with high internal capacity to enable conservation, we described plausible ToCs that involved strengthening policy and regulation. Alternatively, for enabling profiles with low internal enabling capacity, plausible ToCs typically required formalising community-led conservation. Our ‘enabling profile’ framework could be applied to other ecosystems to help operationalise the post-2020 GBF.
A cross-over dietary intervention in captive cheetahs (acinonyx jubatus): Investigating the effects of glycine supplementation on blood parameters
(United States: Wiley Subscription Services, Inc, 2024) Kathryn M. van Boom; Tertius A. Kohn
Captive cheetahs are prone to unusual diseases which may be attributed to their high muscle meat, collagen deficient captive diet. Glycine is a simple amino acid that is abundant in collagen rich tissues and has many physiological functions, specifically in collagen synthesis and in the conjugation of detrimental by-products produced during gut bacterial fermentation. Therefore, the aim of this study was to investigate the effect of a 4 week glycine supplementation on the body measurements, haematology and serum blood parameters of 10 captive cheetahs using a randomised controlled cross-over design. This approach has not yet been used to investigate the effect of diet in captive cheetahs. Cheetahs were randomly assigned to a control diet (horse meat only) or a glycine diet (30 g glycine per 1 kg meat) for 4 weeks before being crossed over. Blood was collected at baseline and after each intervention. The glycine diet resulted in a decreased serum albumin, alkaline phosphatase and total calcium concentration and increases in eosinophils and basophils counts compared to the control diet. Body weight also decreased on the glycine diet which may be due to increased β-oxidation and fat loss. This was the first study to investigate the effect of glycine supplementation, which resulted in slight body and blood changes, in captive cheetahs using a cross-over design and this approach should be utilised for future dietary studies.
Patterned, plain, and in-between: An assessment of ecogeographic divergence between colour pattern morphs of the common egg-eater Dasypeltis scabra
(Taylor and Francis Ltd., 2024) Barends, Jody M; Bassier, Ielhaam; Buckley, Emma E.
Intraspecific variation in colour patterns may reflect adaptive responses to local environmental regimes that favour selection of different trade-offs between visual communication, thermoregulation, and anti-predatory functions. Understanding the drivers of colour pattern variation within species can therefore provide valuable insights about adaptation. However, the ecogeographic correlates, and thus the ecological drivers, associated with the segregation of different colour morphs for most reptile species, including snakes, are not well known. Here, we examined differences in environmental niches associated with occurrence records of preserved museum specimens and georeferenced photographic images of common egg-eaters (Dasypeltis scabra) to characterise ecogeographic divergence between typically patterned, patternless, and faintly marked individuals. We gathered 1707 records that we assigned as either patterned, plain, or intermediate morphs. Most records were of patterned individuals, which were widely distributed in southern Africa. Climate niches differed between morphs as plain and intermediate snakes were restricted to high-elevation areas in the highveld grasslands of South Africa, and woodland-dominated areas in the central and eastern parts of both Zambia and Zimbabwe, but there were no areas where only plain or intermediate snakes occurred in isolation from patterned snakes. Environmental niche modelling predicted minimal areas suitable for co-habitation of colour morphs. We speculate that plain or weakly-marked colour patterns likely developed as an adaptation to increase camouflage ability in open areas in grassland and certain woodland habitats.
Secondarily woody lobostemon and echium (boraginaceae) from two mediterranean-climate biodiversity hotspots share similar wood anatomies
(https://www.scopus.com/record/display.uri?eid=2-s2.0-85203455791&doi=10.1016%2fj.sajb.2024.09.009&origin=inward&txGid=b934f2a818b42b24f67ed0a0333c328b#:~:text=Publisher%3A-,Elsevier,-Source%20type%3A, 2024) Frankiewicz, Kamil E.; Velani, Nopinky; Boatwright, J. Stephen
Lobostemon (Boraginaceae) comprises 28 shrubby species closely related to the herbaceous genus Echiostachys. Both are native to the Greater Cape Floristic Region of South Africa. Together, they form a sister clade to Echium, which is herbaceous except for 23 species that evolved into shrubs and rosette trees on the islands of Macaronesia. Lobostemon and woody Echium make a rare case of parallel evolution of woody habits from herbaceous ancestors (secondary woodiness) in climatically similar but geographically very distant areas. We examined the wood anatomy of 27 Lobostemon species and two of the three species of Echiostachys and compared it with the literature data on woody and herbaceous Echium. Despite differing growth habits, all species share similar wood anatomical traits that may reflect their preference for open, semi-arid habitats. Most conspicuously, there is a common tendency to retain ground tissue cells alive for prolonged periods. In woody species, this results in living fibres and fibre-tracheids. In herbs, it may lead to the total parenchymatization of wood that is devoid of dead cells, except for vessel elements. In Lobostemon, fibre-tracheids with conspicuous pits co-occur with grouped vessels. This may be related to the prolonged retention of protoplasts in ground tissue cells, which hinders water conductance, forcing the development of grouped vessels that can provide a bypass for water in case of embolism. We speculate that in Lobostemon, later-produced wood may contain dead fibre-tracheids and we expect to see less grouped vessels in such case. This potential ontogenetic shift in drought-coping mechanisms requires confirmation.
Gastrointestinal parasite prevalence, diversity and association in free-ranging chacma baboon troops in a semi-arid savanna ecosystem of Zimbabwe
(Australian Society for Parasitology, 2024) Banda, Annabel; Machingura, James; Moyo, Doreen Z
Free-ranging Chacma baboon species are known to harbour a wide range of zoonotic parasites, and their frequent close interactions with humans pose a risk of transmission of zoonotic parasites between the two species. This research study focused on understanding parasite dynamics in free-ranging baboon populations that inhabit human-wildlife interface areas, a case of Gwanda State University’s Epoch Mine campus in Filabusi at Insiza district. A descriptive and analytical cross-sectional design was used to investigate the prevalence, diversity and association of gastrointestinal parasites among three baboon troops found at the Epoch Mine campus. One hundred and twenty (120) fresh faecal samples were collected from the three troops between February and September 2023. The centrifugal floatation technique was used to process and analyse faecal samples, and parasite ova and cysts were identified using morphological features like shape and size. The prevalence of the parasite taxa and a chi-squared multiple comparison test was computed. Results showed significant differences among most parasite taxa except Coccidia spp and Entamoeba spp among the three troops. The Shannon–Wiener (H′) index was used to calculate diversity and graphs were utilized to present the association. The Kruskal-Wallis tests showed no significant difference in parasite diversity among the three troops. Although troop-parasite association showed different parasite species for each troop, helminths Strongylid spp. and Schistosoma spp. were highly common across all three troops. Troop 1 and 3 were associated with four parasite taxa, whereas Troop 2 had only three. The study reveals the presence of gastro-intestinal parasites of public health concern, as they are capable of causing diseases in humans and domestic animals. The study, therefore, underscores the importance of understanding parasite-host dynamics in mitigating zoonotic disease transmission and suggests the need to generate baseline data for mitigating zoonotic diseases and maintaining a healthy ecosystem.
Acoustic cues to development of African penguins (Spheniscus Demersus) begging calls
(John Wiley and Sons Inc, 2024) Zanoli Anna; Ludynia Katrin; Tenneriello Chiara
Avian begging calls mediate parent–offspring conflict and direct parental care to genetically related progeny. We found that the fundamental frequency of begging calls of African Penguins Spheniscus demersus decreases as the penguins age and gain mass, before reaching a lower plateau when the chick reaches about 1 kg. Our results suggest that the food solicitation signals of this species may inform parents of the offspring’s body mass. Our results may also lead to the development of non-invasive tools for facilitating censusing chick growth in wild colonies.
The bii4africa dataset of faunal and floral population intactness estimates across Africa’s major land uses
(Nature Research, 2024) Clements, Hayley; Do Linh San, Emmanuel; Maritz, Bryan
Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species’ population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate ‘intactness scores’: the remaining proportion of an ‘intact’ reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region’s major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.
Systematics of othonna (asteraceae: senecioneae: othonninae) in Southern Africa: the o. Cacalioides l.f., o. Natalensis sch.bip., and o. Osteospermoides dc. groups of species and the identity of o. Frutescens l.
(Elsevier B.V., 2025) Magoswana,Simon Luvo; Boatwright , James Stephen; Magee Anthony Richard
The largely southern African genus Othonna L. (Asteraceae: Senecioneae: Othonninae) is currently the subject of ongoing taxonomic investigations. Here we review the taxonomy of three small species-groups with radiate capitula. The O. cacalioides L.f. species-group comprises five species of dwarf succulents with tuber-like caudex and small capitula; the O. natalensis Sch.Bip. species-group includes two caespitose species from the summer-rainfall Drakensberg Escarpment; and the O. osteospermoides DC. species-group comprises three species of softly woody shrublets with large capitula. We provide descriptions, complete nomenclature and typification, illustrations and geographical distribution of the species. In addition we conclude that the name O. frutescens L. is not an illegitimate superfluous name for Cineraria othonnites L. as has been previously assumed by early authors. The only original material seems to be an illustration and we accordingly select this illustration as lectotype. This illustration matches Othonna coronopifolia L. and we accordingly reduce O. frutescens L. to synonymy under O. coronopifolia L.
Smaller plants in warmer water could have implications for future kelp forests
(Nature Research, 2025) Smit, Albertus; Wernberg, Thomas; Filbee-Dexter, Karen
Global warming is driving contraction of species’ ranges through migration and mortality at their warm edge. However, for most species more subtle, sub-lethal changes in performance will be a more ubiquitous response to the Anthropocene. It has been suggested that reduction in body size will be a universal response to warming for cold-water species. Here we tested this hypothesis for two dominant kelp species in the northern and southern hemispheres, respectively. We tested if populations from cool and warm environments would be morphologically distinct, with warm-water populations displaying structural features indicative of sub-optimal conditions (smaller sizes). We found empirical evidence consistent with size reduction of kelp stipes, blades, and biomass of associated epiphytes from cool to warm water in both hemispheres. These changes are ecologically significant because they affect how kelps engineer their local environment, the three-dimensional habitat they create, and the associated communities they support. Reduced size of cold-water habitat forming species such as kelps may be a sublethal effect of warming that could have widespread but previously overlooked effects on the structure of ecosystems and the services that they provide.
Progress towards the control of invasive alien species in the Cape Floristic Region’s protected areas
(Springer, 2025) Turner, Andrew A.; van Wilgen, Brian W.; Cole, Nicholas S
This paper assesses progress towards the control of biological invasions in 18 protected areas (PAs) covering 677 584 ha in the Cape Floristic Region (CFR), and whether progress has been sufficient to achieve Target 6 of the Kunming-Montreal Global Biodiversity Framework. We used eight indicators for assessing the inputs (quality of the regulatory framework, money spent and planning coverage for species and protected areas), outputs (species and protected areas treated), and outcomes (effectiveness of species and protected area treatments) of management. The estimated money spent over 13 years (2010–2022) was ZAR 976 million, or ZAR 75 million per year. Management plans for PAs were assessed as adequate over 78.5% of the area, but only six out of 226 regulated invasive species had species-specific control plans in place. A total of 567 alien species occurred in the CFR’s PAs, 226 of which were regulated species (i.e. species that had to be controlled), 126 (55.8%) of which received some management. Spending was highly skewed, with over 60% of all funding spent on trees and shrubs in the genus Acacia. Management efforts reached 24% of the land within the CFR’s protected areas, with higher coverage in national parks (60%) than in provincial nature reserves (9%). Management effectiveness was assessed as either permanent, effective or partially effective for 29 species (20 due to biological control), and ineffective for 25; for the remainder, there was either no management or effectiveness could not be evaluated. We conclude that some progress has been made with respect to controlling invasive alien species in the CFR, but that insufficient and declining funding remains a significant barrier to effective management. To increase efficiency, it will be necessary to secure additional funding from more diversified sources, make more use of biological control and prescribed fire, and regularly monitor the outcomes of management.
Red, gold, and green: comparative genomics of polymorphic leopards from South Africa
(Oxford University Press, 2025) McManus, Jeannine; Lagcher, Elina; Bosse, Mirte
An important goal of comparative and functional genomics is to connect genetic polymorphisms to phenotypic variation. Leopards (Panthera pardus) from northern South Africa are particularly diverse, as here a unique color morph occurs, as well as two deeply diverged southern (SA) and central African (CA) mitochondrial clades, stemming from Pleistocene refugia. Here, we present the first whole genomes of a red leopard and a black (captive) leopard, and wildtypes belonging to the CA and SA mitochondrial clades, to evaluate genome-wide diversity, divergence, and high-impact mutations that may relate to their phenotype. In the black leopard, we found long runs of homozygosity (ROHs), low nucleotide diversity across the genome, and a large number of homozygous structural variants, likely resulting from inbreeding to maintain this color morph in captivity. In red leopards, runs of homozygosity were slightly longer compared to wildtype leopards, with potential deleterious mutations relating to its phenotype, including impaired vision. When assessing population structure, we found no divergence between CA and SA leopards and the rest of Africa, whether comparing single nucleotide or structural variants. This illustrates the homogenizing effect of introgression, and highlights that although leopards in northern South Africa may be phenotypically unique, they are not genetically different.
Larger trees facilitate understory herbaceous biomass but not diversity in a South African savanna
(Elsevier, 2025) Samuels, Igshaan; Monegi, Piet
Large single-standing trees contribute to the structural diversity of savannas as they strongly influence their immediate surroundings including soils and understory plant communities. The influence of woody vegetation at a stand level on the understory vegetation has been extensively studied; however, the understanding of the role of single large trees is limited. The objectives of the study were to 1) evaluate the impact of large trees on understory plant species diversity and composition, herbaceous cover and grass standing biomass, and 2) to establish if plant size and functional qualities such as N-fixing ability modulate understory vegetation responses to overstory trees over two growing seasons (January 2022 and 2023). Vachellia tortilis (a leguminous tree) and non-leguminous woody species (Searsia lancea and Ziziphus mucronata) were studied. We systematically selected 30 trees for each woody species and divided them into two size classes (i.e. small and large trees). Understory plant vegetation was assessed using quadrats under and outside the tree canopies. Plant species diversity and abundance were highest under small tree canopies and outside tree canopies, compared to large trees, likely due to the dominance of Megathyrsus maximus under large trees. Megathyrsus maximus dominated under large trees regardless of N-fixing ability. Grass cover increased under large V. tortilis and Z. mucronata, suggesting that evergreen species like S. lancea negatively impact grass cover. Standing grass biomass was higher under large tree canopies than under small trees or outside canopies, with N-fixing ability having no significant effect (p > 0.05), thus, indicating that large trees of both leguminous and non-leguminous woody plants improve grass productivity. The current findings imply that in agrosilvopastoral systems and game farming, where ecological conservation is a priority for farmers, it is essential to have an overstorey composed of both small and large trees to sustain understory diversity and biomass.
Taxonomy of the small south african endemic genus microdon choisy (scrophulariaceae: limoselleae)
(Elsevier B.V., 2025) Maluleke,Rinah; Boatwright,James; Manning,John
The taxonomy of the genus Microdon Choisy (Scrophulariaceae: Limoselleae) is revised. It is a genus of ericoid or microphyllous shrubs separated from Selago L. and other uniovulate members in the tribe by a combination of characters, notably the calyx tube adnate for up to half its length to the bract, with the posticous ovary locule aborted. The entirely eglandular vestiture of the plants is also diagnostic. The plicate calyx is very shortly and sub-equally 5-lobed and glabrous or more usually with spinules on the lower ribs. The flowers are moderately long-tubed with lobes shorter than the tube, and the anticous stamens are shortly included with the posticous pair either exserted or lacking. The fruits are clearly adapted for wind-dispersal, the diaspores shed as a unit comprising the prominent, wing-like bract attached to the calyx that expands to partially or fully enclose the solitary coccus, which remains attached to the receptacle. We recognise seven species in the genus, segregated between sect. Microdon for four species with straight corolla tubes and four stamens with smaller anthers 0.5–1.0 mm long, and sect. Agathelpis for three species with arcuate or geniculate corolla tubes and two stamens with larger anthers ± 2 mm long. The new species M. lyperioides J.C.Manning & R.Maluleke from the Piketberg is distinguished from the sympatric M. dubius by the longer leaves, dense whitish pubescence on the stems, and the markedly patent flowers with longer corolla tube mm 3\0554 mm"?>13–14 mm long and longer corolla lobes 3–4 mm long.
Rejoinder to: cochrane et al., errors and bias in marine conservation and fisheries literature: their impact on policies and perceptions [mar. policy 168 (2024) 106329]
(Elsevier B.V, 2025) Sherley, Richard B.; Crawford, Robert J.M; McInnes, Alistair M.
We agree with Cochrane et al. that misleading science can misinform and is to be avoided. And we agree wholeheartedly that scientists should “strive for objectivity and accuracy” in their writing. Indeed, many of the recommendations in Cochrane et al., are, in our opinion, logical and well-founded. Unfortunately, as we outlined below, Cochrane et al., seem to have failed to follow their own advice to be, “as far as possible, objective and reliable” when it comes to reporting the conclusions of the panel of six scientists that reviewed the issues around penguin-fisheries interactions and the Island Closures Experiment (ICE) in South Africa (hereafter “the ICE panel”), and in their characterisation of Sherley et al, and Sydeman et al., as presenting “misleading findings” and representing “scientific neocolonialism”.
Temporal shifts in key mangrove crab species linked to biotic and abiotic factors at a latitudinal range limit
(Academic Press, 2025) Rajkaran, Anusha; Katharoyan, Chaitanya; Peer, Nasreen
Mangroves in South Africa occur at a southern latitudinal limit (33°12′51″ S, 27°34′54″ E) where distribution is influenced by global climate change. Mangroves are experiencing poleward expansion, affecting the distribution of associated macrofauna. Monitoring surveys have been conducted for South African mangrove macrofauna, with research focusing on drivers of ocypodid crabs rather than grapsoid crabs, despite the key role of grapsoids in this ecosystem. Using uni- and multivariate models, we investigated (i) changes in brachyuran community over time (2016 vs 2023), (ii) the potential biotic (food availability, brachyuran diversity and abundance) and abiotic (sediment, water and geographic parameters) factors influencing occurrence and abundance of three co-occurring mangrove crabs (Austruca occidentalis, Neosarmatium africanum and Cristarma eulimene) along the east coast of South Africa, and (iii) the potential distribution of these three species under climate change scenarios. Brachyuran community structure changed significantly over time (2016–2023) at all mangrove sites sampled (df = 1, pseudo-f = 13.95, p < 0.05). Overall, the presence and abundance of all three species were influenced by total brachyuran abundance and diversity, with latitude also influencing the occurrence of these crabs. Specifically, A. occidentalis occurrence was correlated with sediment organic matter and importance values of mangrove tree species to forest structure, while temperature, salinity and sediment moisture influenced their abundance. The presence and abundance of both sesarmids were driven by microphytobenthos and salinity, while temperature influenced abundance. Both climate change scenarios (SSP245 and SSP585) projected future shifts in distribution of all three crab species, with warmer temperatures and increased rainfall patterns expanding habitat suitability of sesarmids in a poleward direction while contracting fiddler crab ranges. This study highlights the ongoing and future impacts of climate change in South African mangroves and their associated macrofauna, suggesting a projected poleward expansion in response to climate change. Additionally, this study highlights future distributional shifts of mangrove associated crabs that can likely alter coastal ecosystem dynamics.
Vaccination of African penguins (spheniscus demersus) against high-pathogenicity avian influenza
(Wiley, 2024) Roberts, Laura Christl; Ludynia ,Katrin; Abernethy, Darrell
Background: High-pathogenicity avian influenza (HPAI) has become a conservation threat to wild birds. Therefore, suitable vaccine technology and practical application methods require investigation. Methods: Twenty-four African penguins (Spheniscus demersus) were vaccinated with either a conventional inactivated clade 2.3.4.4b H5N8 HPAI whole virus or a tobacco leaf-produced H5 haemagglutinin-based virus-like particle (VLP). Six birds received a second dose of the inactivated vaccine. Antibody responses were assessed and compared by employing haemagglutination inhibition tests. Results: A second dose of inactivated vaccine was required to induce antibody titres above the level required to suppress virus shedding, while a single dose of VLP vaccine produced these levels by day 14, and one bird still had antibodies on day 430. Limitations: Bacterial contamination of the VLP vaccine limited the monitoring period and sample size in that treatment group, and it was not possible to perform a challenge study with field virus. Conclusion: VLP vaccines offer a more practical option than inactivated whole viruses, especially in logistically challenging situations involving wild birds.

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