Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.64898/2026.09.14.751173

A first description of the ichthyofauna of the Namibian Islands Marine Protected Area using baited remote underwater video systems

Leeney, R. H.·De Vos, L.·Simataa, M. A.·van Wyk, A.·Brand, H.·Wilhelm, M. R.·Bernard, A.
View original source ↗Export metadata ↓

Abstract

Data on the diversity, relative abundance and distribution of the ichthyofauna of Namibia's only marine protected area, the Namibian Islands Marine Protected Area (NIMPA), are limited and there is no active monitoring programme in place. Generating a baseline for these species is essential to inform management plans and policy. Baited remote underwater video system (BRUVs) surveys were conducted between 2022 and 2024 in the central eastern NIMPA. Data from 114 BRUVs samples, collected in water less than 45 m deep, were analysed in this study. Of the 17 fish species recorded, five were elasmobranchs, and three fish species - Galeorhinus galeus (CR), Notorynchus cepedianus (VU) and Argyrosomus inodorus (VU) - are classified as threatened on the IUCN Red List. The most frequently recorded elasmobranch, Haploblepharus pictus, was ubiquitous and typified all habitat types and depth categories. The most frequently recorded actinopterygian fish (Clinus spp.) was sighted at 37% of sites. Depth was an important predictor of fish species abundance and community composition, but habitat was not. Both ichthyofaunal relative abundance and diversity appeared lower than in similar surveys in neighbouring South Africa and other temperate waters. Future research should aim to identify the drivers of the observed patterns. The findings provide an important baseline for long-term monitoring of the NIMPA, necessary to better describe biodiversity and inform the development of management strategies.

Explore related subjects

zoologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Leeney, R. H., De Vos, L., Simataa, M. A., van Wyk, A., Brand, H., Wilhelm, M. R., Bernard, A.. 2026-09-16. A first description of the ichthyofauna of the Namibian Islands Marine Protected Area using baited remote underwater video systems. https://doi.org/10.64898/2026.09.14.751173

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

A comprehensive identification protocol for postcranial bones of Southeast Asian Ruminantia. Part 2: Morphological criteria for small and medium-sized species

The taxonomic identification of postcranial elements from small and medium-sized ruminants represents a significant challenge in zooarchaeological and Late Quaternary paleontological studies, particularly in biodiversity-rich regions such as continental Southeast Asia. This study presents a comprehensive osteological reference framework for the small and medium-sized Ruminantia of this region, based on a comparative sample of 228 specimens representing 14 species across three families (Bovidae, Cervidae, and Moschidae). Osteological characters were first described on a small initial specimen set and subsequently scored across the full sample. Although a small number of character states were found to be unique to specific taxa, most proved highly variable, limiting their individual identification potential. To address this, a Random Forest and a Naive Bayes classifier were applied to assess the discriminatory power of character combinations across four taxonomic ranks (Family, Subfamily, Genus, and Species) on independent bones. Both approaches performed similarly, achieving mean identification accuracies of 87-86% at the family level, 69% at the subfamily level, 50% at the genus level, and 35-33% at the species level. The Naive Bayes models were further deployed as an interactive web application, allowing users to perform bone identification based on any combination of observable character states from a single anatomical element. Our results highlight the limits of morphological identification of postcranial elements in this taxonomic and biogeographic context, while demonstrating that a transparent, reproducible, and statistically grounded approach can still represent a significant step forward for zooarchaeological and Late Quaternary paleontological studies in Southeast Asia and beyond.

zoology↗
bioRxiv2026

A comprehensive identification protocol for postcranial bones of Southeast Asian Ruminantia. Part 3: Morphological criteria for large-sized species

Postcranial remains of large-bodied ruminants are abundant in the Late Quaternary record of continental Southeast Asia, yet their taxonomic attribution remains one of the least resolved problems in the zooarchaeology of this biodiversity-rich region. We address it here with an osteological identification protocol covering the six large ruminant species of the mainland: Bubalus bubalis, Bos javanicus, Bos sauveli, Bos gaurus, Budorcas taxicolor and Rusa unicolor, built from a comparative sample of 109 skeletons. A total of 148 discrete characters over 27 skeletal elements representing 442 states were defined on a restricted set of individuals, then scored across the entire sample. Most proved remarkably stable within taxa with 80.0% of the character/taxon combinations showing a dominant state at a frequency above 95%, and a substantial number of states occurred in a single family, subfamily, genus or species. Character combinations for taxonomic identification were then evaluated by the use of two supervised machine learning methods, a random forest model and a naive Bayes classifier at each of four taxonomic ranks. The two behaved almost identically, with mean accuracies of 95-94% for families, 93% for subfamilies, 89% for genera and 76% for species; only the three closely related and unevenly sampled species of Bos resisted consistent separation. The weighted naive Bayes models are distributed as a standalone web application in which any combination of states observed on a single element returns attribution probabilities for every rank. Together these results offer a transparent and statistically explicit alternative to expert judgement for the identification of Late Quaternary postcranial mammal remains, in Southeast Asia and elsewhere.

zoology↗
bioRxiv2026

Note on a Small Chlamyphoridae (Xenarthra, Cingulata) from the Amazon, Brazil

The Awa-Guaja are one of the last hunter-gatherer peoples in the world and live in Indigenous reserves in northwestern Maranhao, Brazil. The Guaja Ethnographic Collection consists of animal remains found during excavations of the community s refuse areas, conducted between 1987 and 1990. This study presents a taxonomic reassessment of a small Cingulata specimen from this collection. The specimen, previously identified as Euphractus sexcinctus, consists of a complete right femur whose taxonomic identity was reevaluated through comparative morphological and metric analyses using specimens from scientific collections and data from the specialized literature. The results revealed that the femur is smaller than those observed in individuals of E. sexcinctus and exhibits a combination of anatomical features resembling those found in the genera Chaetophractus, Cabassous, and Euphractus. Despite these similarities, the observed morphological differences do not allow a reliable identification at the genus level. Therefore, the specimen was provisionally assigned to the family Chlamyphoridae, and its identification was retained at the family level.

zoology↗