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Cowley, P. D.

Publications and source records attributed to Cowley, P. D..

2 recordsLinked to original sources

Genome Assembly of the Roundjaw Bonefish (Albula glossodonta), a Vulnerable Circumtropical Sportfish

BackgroundBonefishes are cryptic species indiscriminately targeted by subsistence and recreational fisheries worldwide. The roundjaw bonefish, Albula glossodonta is the most widespread bonefish species in the Indo-Pacific and is listed as vulnerable to extinction by the IUCNs Red List due to anthropogenic activities. Whole-genome datasets allow for improved population and species delimitation, which - prior to this study - were lacking for Albula species. ResultsWe generated a high-quality genome assembly of an A. glossodonta individual from Hawai i, USA. The assembled contigs had an NG50 of 4.75 Mbp and a maximum length of 28.2 Mbp. Scaffolding yielded an NG50 of 14.49 Mbp, with the longest scaffold reaching 42.29 Mbp. Half the genome was contained in 20 scaffolds. The genome was annotated with 28.3 K protein-coding genes. We then analyzed 66 A. glossodonta individuals and 38,355 SNP loci to evaluate population genetic connectivity between six atolls in Seychelles and Mauritius in the Western Indian Ocean. We observed genetic homogeneity between atolls in Seychelles and evidence of reduced gene flow between Seychelles and Mauritius. The South Equatorial Current could be one mechanism limiting gene flow of A. glossodonta populations between Seychelles and Mauritius. ConclusionsQuantifying the spatial population structure of widespread fishery species such as bonefishes is necessary for effective transboundary management and conservation. This population genomic dataset mapped to a high-quality genome assembly allowed us to discern shallow population structure in a widespread species in the Western Indian Ocean. The genome assembly will be useful for addressing the taxonomic uncertainties of bonefishes globally.

genomics↗

Dietary specialisation in a Critically Endangered pipefish revealed by faecal eDNA metabarcoding

Understanding the dietary preferences of endangered species can be useful in implementing conservation strategies, including habitat restoration, translocation, and captive breeding. Environmental DNA (eDNA) from feces provides a non-invasive method for analyzing animal diets. Currently, metabarcoding, a PCR-based method, is the method of choice for analyzing such data. However, this method has limitations, specifically PCR bias, which can result in the overestimation of the importance of certain taxa and the failure to detect other taxa because they do not amplify. The present study compared metabarcoding with metagenomics, a marker-free method, to assess the diversity of prey items in the feces of a critically endangered South African estuarine pipefish, Syngnathus watermeyeri, and its widely distributed congener (S. temminckii) to investigate the potential dietary competition. Our results showed a distinct difference between the diets of S. watermeyeri and S. temminckii, with the former mainly consuming calanoid copepods and the latter preferring caridean shrimp. Metagenomics produced more species identifications than metabarcoding; however, most of the species identified are not present in South Africa. The identifications made by both methods mostly belonged to the same families, but some prey items were identified only by either method. Both methods would benefit from a complete reference database of South African estuarine macroinvertebrates.

ecology↗