The underexplored marine biodiversity of Brunei and the Palawan-North Borneo ecoregion

David John Marshall

Environmental and Life Sciences, Faculty of Science, Universiti Brunei Darussalam, Brunei Darussalam

The numerous studies undertaken to document the marine biodiversity of Brunei over the past two decades by university scientists, the oil and gas industry, and govenment agencies, are strongly biased in terms of the marine taxa and ecosystems considered. Studies have primarily focussed on fishes and coral reef systems, with relatively little known about the non-coral benthic animals and the invertebrate diversity of the country and the Palawan/North-West Borneo ecoregion in which it lies. This talk presents an overview of recent research undertaken at UBD on benthic faunal diversities, with the aim of addressing this knowledge gap. Specifically, new data will be presented for samples of the Brunei shelf foraminiferans and pteropods, coastal decapod crustaceans, horseshoe crabs and gastropod molluscs. These findings highlight a striking lack of knowledge of these taxa, which are diverse, functionally important, and can be used as indicators of environmental change. This study reveals the importance of taxonomic inclusiveness and resolution to ultimately spatially define the marine biotopes and ecosystems in the country, crucial to marine environmental management and conservation.

 Systematic conservation planning in the marine environment

Stelios Katsanevakis¹, Antonios Mazaris²

¹Department of Marine Sciences, University of the Aegean, Greece

²Department of Ecology, School of Biology, Aristotle University of Thessaloniki, Greece

An introduction to Systematic Conservation Planning in the framework of Maritime Spatial Planning is provided. The available decision support tools for spatial prioritization of sites for protection are presented, with an emphasis on the Marxan family of tools. We present the key objectives, context and challenges of spatial prioritization tools which are widely applied for selecting areas for protection, conservation and restoration at different spatial scales in both terrestrial and marine environments.  An example of Systematic Conservation Planning study in the Aegean Sea is given, made in the framework of the MARISCA project (https://www.marisca.eu/).

 

Incorporating climate change into spatial prioritization of Marine Protected Areas

Antonios D. Mazaris

Department of Ecology, School of Biology, Aristotle University of Thessaloniki, Greece

Currently, the identification of priority areas for conservation, the design of protected areas networks and the zoning where specific activities should take place, are based on information on the present distribution of biological features. Here we present a set of tools on how climate change could be incorporated into spatial prioritization. We present a novel 4D-approach (3^rd dimension is depth, 4^th dimension is time) for designing marine protected areas, integrating climate change impacts. This method uses projected species distributions alongside climatic stability and heterogeneity metrics. Our proposed approach identifies key areas for conservation, emphasizing a three-dimensional, climate-smart approach to protected area networks. In addition, we discuss how changes in the distribution of species, marine heatwaves and biotic interactions could be considered into the analysis.

 

Methods for non-native species detection and impact assessment

Stelios Katsanevakis

Department of Marine Sciences, University of the Aegean, Greece

The Mediterranean Sea is provided as an example of the implementation of methods for non-native species detection and assessing their impacts. In this region, diverse methods are utilized, including scientific and fisheries surveys, citizen science networks, online databases, open-access journals, and advanced molecular techniques, achieving comprehensive spatial and temporal coverage. Such datasets of non-native species distribution combined with impact assessments using manipulative and natural experiments, models, and expert analysis have allowed large-scale regional assessments of non-native species’ cumulative impacts. For this, a conservative additive model was developed to account for the Cumulative IMPacts of invasive ALien species (CIMPAL) on marine ecosystems. CIMPAL calculates impact scores by integrating species distributions, habitat data, ecological impact magnitude, and evidence strength.

 

Marine biological invasions: pathways, impacts, and management options

Stelios Katsanevakis

Department of Marine Sciences, University of the Aegean, Greece

An account of the main pathways of introduction of non-native species, their impacts on biodiversity and ecosystem services, and management options is provided, based on the European example. European studies identify competition, habitat alteration, and predation as major negative impacts of Invasive Alien Species (IAS), but the creation of novel habitats represents also a key mechanism for positive impacts. Preventing IAS introductions is critical, and measures such as ballast water treatment systems are implemented to reduce the likelihood of marine introductions. However, understanding introduction pathways remains uncertain for many IAS. Eradication and control efforts for marine IAS have limited success, emphasizing the need for enhanced biosecurity measures. Climate change exacerbates IAS impacts, necessitating integrated management approaches considering climate interactions. Effective management involves securing funding, learning from successful biosecurity models, maintaining information systems, enhancing monitoring and prediction tools, and conducting comprehensive impact assessments, including potential ecosystem benefits of IAS.

 Sea turtles research: current knowledge and challenges

Antonios D. Mazaris

Department of Ecology, School of Biology, Aristotle University of Thessaloniki, Greece

Sea turtles have left an indelible mark on our planet, with a presence spanning an impressive 50-100 million years, making them one of the most ancient groups of animals. Sea turtles are not only crucial components of marine ecosystems but also possess significant cultural and economic value to human societies. These remarkable creatures are characterized by their extended lifespans, often taking many decades to reach sexual maturity. Sea turtles exhibit a fascinating and complex life-history pattern encompassing various life stages in different habitats and geographic locations. Here, current knowledge on sea turtle ecology is presented, challenges for their conservation are discussed and potential research targets are raised. 

 

Ecology, diversity and conservation of tropical anguillid eels in Southeast Asia

Takaomi Arai

Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Gadong, BE 1410, Brunei Darussalam

Email: takaomi.arai@ubd.edu.bn

Anguillid eels are exotic animals, and despite a huge number of scientific studies conducted with eels, crucial aspects of their biology remain a mystery. The eels are the most important of the eel families from a conservation standpoint because they have a unique catadromous life history and are used as food resources. Among the anguillid eels, 13 species/subspecies are distributed in tropical areas and the remaining six species and subspecies occur in temperate areas. Recently, however, the juvenile population has declined dramatically, likely due to wild juveniles being used in cultivation. These eels are captured in estuaries. Almost all of the world’s total eel supply comes from aquaculture. Therefore, the supply of eel resources for human consumption is completely dependent on wild catch. The causes of decline in stock and recruitment are not well understood. Overfishing, habitat loss, migration barriers, increased natural predation, parasitism, ocean climate variation, and pollution all might have an impact. Since the European eel was listed by CITES under Appendix II and came under protection in March 2009, and since the export/import ban was issued by the EU in 2010, the international trade of juvenile eels has changed. Most recently, the Japanese and American eels were added to the IUCN’s list with an endangered classification, suggesting they have a high risk of extinction. Although there are fewer data available for tropical anguillid eels, conservation concerns also exist for many of these species including A. bicolor rated as Near Threatened. In the future, further eel species could be classified as endangered without comprehensive conservation and protection. We may not be able to see such a unique animal on the earth in the near future.

 The oysters of Brunei and their role as habitat facilitators

Lee Huan Chiao

Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Gadong, BE 1410, Brunei Darussalam

The engineering of environmentally detrimental marine structures is necessary to reduce coastal erosion and sea encroachment in the wake of sea level rise and urbanization. The South China Sea shoreline of Brunei is predominated by sandy beaches and artificial rocky shores comprised of seawalls made from concrete boulders. These seawalls were not built with the purpose of enhancing biodiversity, yet they harbor up to a hundred species due to their unnatural structures which facilitate an environment enhancing species colonization and settlement. We present the concept of a three-tiered ecological engineering driven by human intervention and species colonization, which involves a cascade of habitat engineering and modification spanning the planes of the seawall down to a microscale that eventually leads to the formation of a complex and biodiverse ecosystem on a barren seascape. The knowledge of marine fauna in Brunei is largely skewed with many non-commercial benthic taxa and their ecosystem services remaining obscure, and understanding the natural wealth our ocean harbor is crucial to maximize the potential of our conservational strategies, resource management and maritime policies.

Population genetic structure of Pterobdella arugamensis In the Indo-West Pacific region

Syakirah Azmey

Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Gadong, BE 1410, Brunei Darussalam

Grouper aquaculture is prospering in tropical and subtropical regions, yet the persistent presence of marine leeches poses a severe threat to production, causing substantial economic losses. Understanding the population structure of these leeches is crucial for identifying distributional patterns and implementing effective monitoring and mitigation strategies. Marine leeches samples were collected from cultured hybrid groupers (Epinephelus spp.) in Brunei Darussalam, Malaysia, and Indonesia. Their DNA samples were extracted and their population genetic analyses were conducted to assess the structure of the marine leech populations. The findings based on the mitochondrial cytochrome c oxidase subunit I gene sequence analyses revealed that the marine leeches were P. arugamensis, and there are four distinct haplogroups: (1) Asia Pacific, (2) Borneo, (3) Surabaya, and (4) Iran. Notably, these populations exhibited significant genetic divergence. The results suggest a complex distributional pattern. Particularly, samples from the Asia Pacific population may indicate dispersion and transport from Indonesia. This insight into the genetic diversity and distributional mechanisms of marine leeches contributes to a comprehensive understanding of the factors influencing grouper aquaculture infestation. The implications of this research extend beyond academic curiosity, as it provides a foundation for developing targeted strategies to monitor and mitigate marine leech infestations in grouper aquaculture. By identifying the distributional origins and mechanisms, stakeholders can implement region-specific interventions to safeguard grouper aquaculture production and mitigate economic losses. In conclusion, the findings underscore the importance of genetic analyses in elucidating the complex population structure of marine leeches, offering valuable insights for the sustainable management of grouper aquaculture in Southeast Asia.