Research Articles (Biodiversity and Conservation Biology)

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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.
Caught in transition: changes in brachyuran diversity following mangrove encroachment into saltmarshes at a southern distribution limit
(Frontiers Media SA, 2024) Katharoyan, Chaitanya; Rajkaran, Anusha; Peer, Nasreen
Mangroves are expanding polewards due to global change, often encroaching into adjacent temperate saltmarshes. In both vegetated ecosystems, brachyurans are responsible for ecological processes and functions such as nutrient cycling and sediment bioturbation. South African mangroves occur at a latitudinal limit and are establishing further south due to past planting events and global change, making these ideal study systems for the effects of mangrove expansion and encroachment. Here, we investigated the effect of mangrove encroachment on brachyuran community composition at two saltmarsh sites with planted mangrove stands of different ages. Transects were laid perpendicular to each estuary where three habitat types were demarcated (mangrove, ecotone, saltmarsh). Sediment samples were collected for analyses and quadrats were used to measure pneumatophore density, saltmarsh cover, and brachyuran abundance and diversity. We found that brachyuran community structure at each site has significantly changed over seven years, with two mangrove-associated fiddler crab species, Tubuca urvillei and Paraleptuca chlorophthalmus, now recorded at the younger planted site, indicating a new southern distributional limit.
Introducing the seaweed specialist group of the IUCN species survival commission
(Cambridge University Press, 2024) Arafeh-Dalmau, Nur; Smit, Albertus; Erlania
In June 2023, the IUCN Species Survival Commission created the Seaweed Specialist Group. This international group of scientists and practitioners will work to assess and improve the conservation status of seaweeds, build networks and partnerships to prioritize conservation actions and communicate the importance of seaweed species. Seaweeds (macroalgae) are found in all oceans and seas, with > 10,000 known marine species that include the red (Rhodophyta, c. 6,200 species), brown (Ochrophyta, c. 1,800) and green (Chlorophyta, c. 1,800) taxa. However, climate change and other anthropogenic stressors threaten many seaweeds globally, including iconic habitat-forming species such as kelps, fucoids and rhodoliths.
Inclusion of ecosystem services in the management of municipal natural open space systems
(John Wiley and Sons Inc, 2024) Wessels, Nadia; O'Farrell, Patrick; Sitas, Nadia
Unprecedented urbanisation in the global south is transforming natural urban landscapes, impacting on the ability of nature to provide essential ecosystem services. Within the context of pressures facing many urban natural open spaces, particularly in Africa, we used a local municipality in South Africa as a case study to (i) identify local government priorities for a natural open space system; (ii) develop an understanding of whether, and how, ecosystem services are considered by local government, and the reasons thereof; and (iii) ascertain the extent of proactive planning regarding regulating and other ecosystem services, including the temporal and spatial scales, and implications. In-depth qualitative interviews (n = 12) were undertaken with senior municipal officials representing departments whose work impacts the environment. Municipal decision-support documents were also analysed for any direct and/or indirect references to ecosystem services. Planning for, and management of, ecosystem services provided by natural open spaces is influenced by interwoven infrastructure, municipal service delivery and equity challenges, complex institutional constraints and poverty, with little focus on the socio-economic opportunities and other benefits of natural open space systems. Values, perceptions and knowledge also influence the management of ecosystem services.
Commercial fishery no-take zones for African penguins minimize fisheries losses at the expense of conservation gains
(Oxford University Press , 2024) McInnes, Alistair M ; Barham, Peter; Weideman, Eleanor A.
The African penguin population has declined precipitously in recent decades, and if current rates of decline persist, this species could become extinct in the wild by 2035. Resource extraction of small pelagic fish prey by the purse-seine fishery around African penguin breeding colonies has been identified as a demographically meaningful threat to African penguins. Consequently, long-term, effective no-take zones around breeding colonies have been endorsed by an expert panel of scientists constituted by the South African government. Here, we consider the six largest South African penguin colonies that currently hold 76% of the global population. We evaluate the adequacy of different no-take zone options using a trade-off mechanism recommended by the expert panel. For all six colonies except Bird Island, Algoa Bay, which is subject to the least fishing pressure, the current no-take zone delineations are assessed as having little benefit to the African penguin and little to no cost to the purse-seine fishery. Four of the six current no-take zones include ≤50% of the African penguins’ core foraging areas. Alternative no-take zones that approximate a more balanced trade-off offer more impactful alternatives to the current fisheries restrictions. Given the urgent need to implement evidence-based conservation interventions for the endangered African penguin, we recommend the substitution of the current no-take zones with those proposed herein.
Secondarily woody lobostemon and echium (boraginaceae) from two mediterranean-climate biodiversity hotspots share similar wood anatomies
(Elsevier B.V., 2024) Boatwright, J. Stephen; Velani, Nopinky; Manuel, Robyn
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.
A framework for optimising opportunistic collaborative syntheses to propel ecological conservation
(Elsevier Ltd, 2024) Sequeira, Ana M.M.; Sherley, Richard B.; Bates, Amanda E.
Ecological data are being opportunistically synthesised at unprecedented scales in response to the global biodiversity and climate crises. Such syntheses are often only possible through large-scale, international, multidisciplinary collaborations and provide important pathways for addressing urgent conservation questions. Although large collaborative data syntheses can lead to high-impact successes, they can also be plagued with difficulties. Challenges include the standardisation of data originally collected for different purposes, integration and interpretation of knowledge sourced across different disciplines and spatio-temporal scales, and management of differing perspectives from contributors with distinct academic and cultural backgrounds. Here, we use the collective expertise of a global team of conservation ecologists and practitioners to highlight common benefits and hurdles that arise with the development of opportunistic collaborative syntheses. We outline a framework of “best practice” for developing such collaborations, encompassing the design, implementation, and deliverable phases. Our framework addresses common challenges, highlighting key actions for successful collaboration and emphasizing the support requirements. We identify funding as a major constraint to sustaining the large, international, multidisciplinary teams required to advance collaborative syntheses in a just, equitable, diverse, and inclusive way. We further advocate for thinking strategically from the outset and highlight the need for reshaping funding agendas to prioritize the structures required to propel global scientific networks. Our framework will advance the science needed for ecological conservation and the sustainable use of global natural resources by supporting proto-groups initiating new syntheses, leaders and participants of ongoing projects, and funders who want to facilitate such collaborations in the future.
Pastoral coping and adaptive management strategies to climate change in communal areas in Namibia and South Africa
(Springer Nature, 2024) Ntombela, Khululiwe Primrose; Samuels, Igshaan; Angula, Margaret
Climate change has brought about credible changes in arid landscapes which have resulted in further challenges for pastoralists who require good quality rangeland resources to sustain their livestock. This study assessed local level coping and adaptive management strategies by pastoralists in Namibia and South Africa using a capital assets approach, and also explored non-climate related barriers that increase their vulnerability to climate change. A case study approach was used, which included focus group discussions and semi-structured interviews. The main findings of the research indicate that pastoralists have been exposed to increased temperature extremes and droughts of varying duration over time which reduced the quality and quantity of forage and resulted in losses of income and animal health. The 46 different coping and adaptation strategies used by pastoralists included financial (n = 15), natural (n = 15), human (n = 12), physical (n = 2) and social (n = 2) capital. Of these, 61% of the strategies were common between the two countries. Strategies included income diversification, supplementary feeding and livestock mobility. Pastoralists had to overcome a hierarchy of barriers to implement their coping and adaptation strategies, which were largely related to human capital in Namibia and to natural capital in South Africa. These barriers included a lack of access to grazing lands, land degradation and the loss of traditional knowledge to manage livestock and rangeland resources. Policy development should take these barriers into account while building on the foundation of existing adaptation strategies to reduce the vulnerability to climate change of pastoralists in dryland regions.
Convivial fences? property, ‘right to wildlife’ and the need for redistributive justice in South African conservation
(Elsevier, 2024) Büscher, Bram; Thakholi, Lerato
In South Africa, fences are ubiquitous. From urban centers to rural landscapes, myriad fences divide properties, fortify estates, and protect private interests. In biodiversity conservation, likewise, fences are instrumental in legally assigning property rights over wildlife. They are furthermore deemed necessary to avoid human-wildlife conflict, save human and animal lives and, most of all, safeguard wildlife properties for the benefit of their state or private owners. This normalization of fences and private property has, in practice, meant that colonial and apartheid-era racialized spatial injustices have not only often been maintained, but also progressively hardened in the democratic era. Overcoming these injustices inevitably means confronting the question of private property and the fences that protect them. This article does so by connecting debates on fences, private property and wildlife protection to emerging discussions around convivial conservation that seek to transform the conserva tion sector by combining biodiversity conservation with social justice concerns. It asks: can fences ever be convivial? The answer, like fences themselves, is not straightforward. Reflecting on historical, policy and legal discussions, as well as the authors extensive research on the South African conservation sector over the past decades, the article proposes a conceptual heuristic around processes of softening and hardening of both fences and property in order to challenge continuing processes of dispossession, injustice and unsustainable forms of conservation. Based on this heuristic, the article suggests various strategies, including a ‘right to wildlife’ and a ‘wildlife restitution’ process, to support redistributive justice in South African conservation.
Revisiting the sustainability science research agenda
(Springer, 2024) Sahle, Mesfin; O’Farrell, Patrick; Lahoti, Shruti Ashish
Identifying research gaps and priorities is paramount to advance sustainability science and contribute to a sustainable future. This editorial contributes to this effort by contemplating the sustainability science research agenda and aligning it with recent changes in global dynamics. Drawing on consultations with the editorial board members of the Sustainability Science journal and a review of relevant literature, we identified 12 key research topics. These topics are interpreted within a strategic framework encompassing three key themes: (1) goals that drive sustainability science, (2) approaches to attain these goals, and (3) tools to advance sustainability science research. In so doing, this editorial emphasizes a sustainable development agenda extending beyond 2030, fostering equity and justice, and tackling issues related to power dynamics and geopolitical conflicts. It underscores the significance of research approaches to attaining sustainability goals, in particular, theorizing, coproduction of knowledge and action, attaining clarity in conceptual descriptions, and developing systems-oriented analytical frameworks. Additionally, it highlights the value of place-based approaches, learning from significant systemic shocks, and nurturing inner transformations. It also underlines the need to explore emerging technologies and data-intensive methodologies as a tool to address sustainability concerns. The systematic contemplation of the sustainability science research agenda presented in this editorial piece aims to invoke further discussion among researchers and practitioners about a fresh and relevant agenda that promotes the sustainable integration of nature and society
p-Coumaric acid differential alters the ion-omics profile of chia shoots under salt stress
(MDPI, 2024) Badiwe, Mihlali; Nkomo, Mbukeni; Niekerk, Lee-Ann
p-Coumaric acid (p-CA) is a phenolic compound that plays a crucial role in mediating multiple signaling pathways. It serves as a defense strategy against plant wounding and is also presumed to play a role in plant development and lignin biosynthesis. This study aimed to investigate the physiological and ionomic effect of p-CA on chia seedlings under salt stress. To this end, chia seedlings were supplemented with Nitrosol® containing 100 μM of p-CA, 100 of mM NaCI, and their combined (100 mM NaCI + 100 μM p-CA) solutions in 2-day intervals for a period of 14 days along with a control containing Nitrosol® only. The treatment of chia seedlings with 100 mM of NaCI decreased their growth parameters and the content of the majority of the essential macro-elements (K, P, Ca, and Mg), except for that of sodium (Na). The simultaneous application of p-CA and a salt stress treatment (p-CA + NaCI) alleviated the effect of salt stress on chia seedlings’ shoots, and this was indicated by the increase in chia biomass. Furthermore, this combined treatment significantly enhanced the levels of the essential microelements Mg and Ca. In summary, this brief report is built on the foundational work of our previous study, which demonstrated that p-CA promotes growth in chia seedlings via activation of O2 −. In this brief report, we further show that p-CA not only promotes growth but also mitigates the effects of salt stress on chia seedlings. This mitigation effect may result from the presence of Mg and Ca, which are vital nutrients involved in regulating metabolic pathways, enzyme activity, and amino acid synthesis.
Kelp holdfasts in the Great African Seaforest provide habitat for diverse assemblages of macroinvertebrates
(Inter-Research, 2024) Samaai, Toufiek; Katharoyan, Chaitanya; Peer, Nasreen
Kelp forests along the southwestern and west coasts of South Africa, dominated by the species Ecklonia maxima and Laminaria pallida, are locally termed ‘the Great African Seaforest’. They form 3-dimensional biogenic habitats that provide 4 distinct microhabitats—canopy, fronds, stipe and holdfast—with the latter typically supporting the highest abundance and diversity of associated macroinvertebrates. The macrofauna inhabiting kelp holdfasts in South Africa have rarely been studied, resulting in a near complete lack of baseline data. In this study, macrobenthic assemblages from 40 E. maxima holdfasts were examined over 2 marine ecoregions and 4 locations. Macroinvertebrates were identified and counted for univariate and multivariate analyses using family-level data. A total of 120 families from 9 phyla were identified and were generally dominated by Arthropoda (48 families), Annelida (24 families) and Mollusca (23 families). Marine ecoregion had no significant effect on composition of macroinvertebrate assemblages, whereas location had a significant effect. There was no significant relationship between holdfast volume and macroinvertebrate diversity or abundance, suggesting that other environmental and physicochemical factors are important in determining community structure. This study serves as a baseline for future research aimed at understudied holdfast macroinvertebrate communities in the Great African Seaforest.
A complete guide to the snakes of Southern Africa
(African Journal of Herpetology, 2023) Maritz, Bryan
Background: The new edition of A Complete Guide to the Snakes of Southern Africa represents the third iteration in a series of books that started three decades ago. The latest edition replaces the 2004 edition (Marais Citation2004)—an excellent book in its own right (Bauer Citation2004). In the nearly two decades since the last edition, there have been several important advances in the study of snakes in southern Africa. These include changes in systematics and the description of new species, a substantial formalisation of conservation assessment processes, and the remarkable growth of citizen/community science platforms that have improved the quantity and quality of geographic distribution data and natural history information
Nitrogen fertilization increases the growth and nutritional quality of the forage legume, calobota sericea – A preliminary investigation
(Heliyon, 2023) Britz, Ethan; Cyster, Lilburne; Samuels, Igshaan; Clement, Cupido
Calobota sericea is being evaluated as a forage for drought stressed areas. The nutritional quality of C. sericea from native populations are poor, and this is believed to be due to poor soil fertility. Therefore, a greenhouse trial was established to determine the impact of N-fertilization level (0, 25, 50, 75 and 100 kg/ha) on the growth and nutritional quality of C. sericea plants. Three-month-old plants were harvested and the root and shoot length, as well as branching intensity on each plant determined. Thereafter, the shoots were separated into leaves and stems and all plant parts were oven dried for dry mass determination. After weighing, the leaves and stems for each plant were combined and the dried shoots used for nutrient determination.
Taxonomy of the small southern African endemic genus Echiostachys Levyns (Boraginaceae: Boraginoideae)
(South African Journal of Botany, 2023) Velani, N; Boatwright, J.S; Magee, A.R
The small genus Echiostachys Levyns (Boraginaceae: Lithospermeae) is revised. It was segregated from Lobostemon Lehm. on the basis of the herbaceous habit, radical foliage, spiciform inflorescence, slightly accrescent calyx, and lack of staminal scales. Three species are recognised. An identification key, descriptions, full nomenclature, illustrations, and distribution maps are provided.
Stakeholder-derived recommendations and actions to support deep-reef conservation in the Western Indian Ocean
(Wiley, 2022) Stefanoudis, Paris V.; Talma, Sheena; Samaai, Toufiek
Deep reefs below 30mprovide essential ecosystem services for ocean health and human well-being such as food security and climate change resilience. Yet, deep reefs remain poorly researched and largely unprotected, including in the Western Indian Ocean (WIO). Here, we assessed current conservation approaches in the WIO focusing on deep reefs, using a combination of online surveys and semi-structured interviews. Results indicated that deep-reef data are sparse and commonly stemming from non-peer-reviewed or non-publicly available sources, and are often not used to inform conservation of WIO marine protected areas.
Descriptive epidemiology of and response to the high pathogenicity avian influenza (h5n8) epidemic in South African coastal seabirds, 2018
(Wiley, 2023) Roberts, Laura C.; Abolnik, Celia; Waller, Lauren J.
High pathogenicity avian infuenza (HPAI) clade 2.3.4.4b H5N8 virus was detected in coastal seabirds in late 2017 in South Africa, following a devastating epidemic in the commercial poultry and ostrich industries. By May 2018, the infection had been confrmed in ffteen seabird species at 31 sites along the southern coast, with the highest mortality recorded in terns (Family Laridae, Order Charadriiformes). Over 7,500 positive or suspected cases in seabirds were reported. Among those infected were three endangered species: African penguins (Spheniscus demersus Linnaeus, 1758), Cape cormorants (Phalacrocorax capensis Wahlberg, 1855), and Cape gannets (Morus capensis Lichtenstein, 1823). Te scale and impact of this outbreak were unprecedented in southern African coastal seabirds and raised logistical challenges in resource allocation, risk mitigation, and outbreak response. It required the collaboration of multiple stakeholder groups, including a variety of government departments and nongovernmental organizations. With another HPAI outbreak in South African seabirds in 2021 and major incursions in seabird species in the northern hemisphere in 2022, it is vital to share and consolidate knowledge on the subject. We describe the epidemic, the lessons learned, and recommendations for developing contingency plans.
Initial evaluation of the care and rehabilitation success of Cape Cormorants Phalacrocorax capensis rescued from Robben and Jutten islands, South Africa, in January 2021
(Taylor and Francis Group, 2023) Phillips, Jesse; Ludynia, Katrin; Waller, Lauren J
The population of the endangered Cape Cormorant Phalacrocorax capensis more than halved over the last three decades (BirdLife International 2018a). In January 2021, nearly 2 000 Cape Cormorant chicks were found abandoned, suffering from dehydration and heat stress, at two important nesting sites. The chicks were rescued and rehabilitated by the Southern African Foundation for the Conservation of Coastal Birds (SANCCOB, Cape Town, South Africa). About half (53.7%) of the cormorant chicks were successfully rehabilitated and released back into the breeding colonies. This study found a direct link between the initial body mass of cormorant chicks admitted to the rehabilitation centre and their probability of surviving during rehabilitation, with birds that were initially heavier having a greater probability of eventual release. Most cormorant chicks that died (80.7%) did so within the first 5 days of admission. This rescue required SANCCOB to care for and rehabilitate the largest number of Cape Cormorant chicks that has ever been admitted to its rehabilitation centre at one time, making it the first rescue of its kind. Despite the presumably limited positive impact on overall population numbers of Cape Cormorants, the rescue campaign improved SANCCOB’s preparedness to respond successfully to future disaster events and to deal with different species, both locally and globally.
The diurnal activity budgets of extralimital giraffe (Giraffa camelopardalis giraffa) in the Western Cape Province, South Africa
(Wiley, 2023) Paulse, Jamie; Couldridge, Vanessa; Cupido, Clement
Despite being an extralimital species in the region, South African giraffes (Giraffa camelopardalis giraffa, Schreber 1784) are continuously being introduced into the Albany Thicket Biome of the Western Cape Province of South Africa. This study aimed to determine the diurnal activity budgets of two extralimital giraffe populations in the Western Cape of South Africa. Diurnal activity budgets are important to provide baseline information on the adaptability of species in newly introduced areas and for more detailed ecological studies such as those relating to habitat suitability, animal–plant interactions and interactions with other resident animals.
Implications of the breakdown in the indigenous knowledge system for rangeland management and policy: A case study from the Eastern Cape in South Africa
(Taylor and Francis Group, 2023) Finca, Andiswa; Linnane, Suzanne; Samuels, M Igshaan
Communal rangelands in South Africa are generally perceived as overgrazed owing to complexities in their histories and collective utilisation which often leads to improper management. A suitable solution has not been found in land management policies because local people’s contexts and their indigenous knowledge are ignored. Hence, this paper is aimed at (i) assessing the role indigenous knowledge can play in communal rangeland management, (ii) exploring working solutions to incorporate indigenous knowledge into effective communal rangeland management and land use policies, (iii) assessing mechanisms for generational transfer of indigenous knowledge. Findings from the Participatory Geographic Information System (PGIS) and Focus Group Discussion, conducted with Cata and Guquka villages in the Eastern Cape province were synthesised. This revealed that communal farmers have in-depth knowledge of their communal land, past and present rangeland management strategies and changes in rangeland condition. However, there is breakdown in the indigenous knowledge system whereby this knowledge is not being transferred and translated into good rangeland management practice, owing to the ageing population of communal farmers, limited youth involvement in livestock farming and limited access to extension services. This suggests a need for new policy approaches that would include participation of local people in policy planning and development.

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