Aurelien Delaval

• Doctor of Philosophy
• Researcher at Institute of Marine Research in Norway

The blue skate (Dipturus batis) has a patchy distribution across the North-East Atlantic Ocean, largely restricted to occidental seas around the British Isles following fisheries-induced population declines and extirpations. The viability of remnant populations remains uncertain, and could be impacted by continued fishing and bycatch pressure and t...

Estimating the demographic parameters of contemporary populations is essential to the success of elasmobranch conservation programmes, and to understanding their recent evolutionary history. For benthic elasmobranchs such as skates, traditional fisheries-independent approaches are often unsuitable as the data may be subject to various sources of bi...

Polyploidy occurs naturally across eukaryotic lineages and has been harnessed in the domestication of many crops and vertebrates. In aquaculture, triploidy can be induced as a biocontainment strategy, as it creates a reproductive barrier preventing farm‐to‐wild introgression, which is currently a major conservation issue for the industry. However,...

Species within the northwest Australian clade of Hypseleotris (six species) and the genus Kimberleyeleotris (two species) are reviewed following the recording of new populations in the region and a molecular study of the group that identified three undescribed candidate species. Based on the analysis of extensive morphological and nuclear and mitoc...

Triploid fish are usually sterile, a trait which reduces unwanted sexual maturation in fish farming and eliminates the risk for negative genetic effects of escapees on wild stocks. The triploid state, normally established through a doubling of the maternal genome, consists of two chromosome sets from the mother and one from the father. The increase...

In commercial aquaculture, the production of triploid fish is currently the most practical approach to prevent maturation and farm-to-wild introgression following escapes. However, triploids often exhibit poor welfare, and the underlying mechanisms remain unclear. Inheritance issues associated with sub-optimal hydrostatic pressure treatments used t...

In commercial aquaculture, the production of triploid fish is currently the most practical approach to prevent maturation and farm-to-wild introgression following escapes. However, triploids often exhibit poor welfare, and the underlying mechanisms remain unclear. Inheritance issues associated with (sub-optimal) hydrostatic pressure treatments used...

Elasmobranchs (sharks, skates, rays and sawfishes) are among the oldest and most diverse groups of marine vertebrates. They serve important ecological functions in marine food webs such that they are often considered as indicators of a healthy ecosystem. Many are also of significant socio-economic value to humans, having historically been an import...

We describe the complete mitochondrial genomes of the flapper skate Dipturus intermedius (Parnell 1837) and the longnose skate Dipturus oxyrinchus (Linnaeus 1758), which have been obtained by Sanger sequencing. We report the length of the sequences to be 16,906 and 16,911 bp, respectively. The length and structure of gene regions, containing 13 pro...

Background In species showing partial migration, as is the case for many salmonid fishes, it is important to assess how anthropogenic pressure experienced by migrating individuals affects the total population. We focused on brown trout ( Salmo trutta ) from the Guddal River in the Norwegian Hardanger Fjord system, which encompasses both resident an...

Sagittal otoliths are calcareous structures in the inner ear of fishes involved in hearing and balance. They are usually composed of aragonite; however, aragonite can be replaced by vaterite, a deformity which is more common in hatchery-reared than in wild fish. Vaterite growth may impair hearing and balance and affect important fitness-related beh...

Background: In species showing partial migration, as is the case for many salmonid fishes, it is important to assess how anthropogenic pressure experienced by migrating individuals affects the total population. We focused on brown trout (Salmo trutta) from the Guddal River in the Norwegian Hardanger Fjord system, which encompasses both resident and...

The systematics of the genus Hannia Vari 1978, endemic to freshwater habitats of remote northwestern Australia, is revised in light of recent collections in the region and a molecular study of the group that identified an undescribed candidate species. A new freshwater fish species (Hannia wintoni sp. nov) is described based on analysis of multiple...

The complete mitochondrial genome of the blue skate Dipturus batis is described from shotgun sequencing on an Illumina next-generation sequencing platform. We report a 16,911 bp long sequence similar in size to other members of the genus, containing 13 protein-coding regions, 22 tRNA genes, 2 rRNA genes, and 2 non-coding areas. Phylogenetic analysi...

The bearded goby Sufflogobius bibarbatus is an abundant endemic small fish species on the continental shelf of the northern Benguela. The goby habitat is characterised by generally low bottom oxygen concentrations that vary spatially and seasonally. In the present study of population structure, 13 samples of S. bibarbatus from inner and outer shelf...

The roundnose grenadier Coryphaenoides rupestris is a benthopelagic fish distributed along the continental, island, and seamount slopes of the North Atlantic and Mid-Atlantic Ridge. Previous studies have indicated that C. rupestris consists of sub-populations across its distribution range, but no study has addressed small-scale population structuri...

The systematics of the genus Syncomistes Vari, 1978 endemic to freshwater habitats of remote northwestern Australia, is reviewed in light of recent collections in the region and a fine scale molecular study of the group that identified new taxa. Based primarily on external morphology, seven taxa are described as new: Syncomistes bonapartensis sp. n...