Romina Henriques

• PhD
• Senior Lecturer at University of Pretoria

Adaptive management is critical to maintaining resilient fisheries in our rapidly changing ocean environments. However, establishing appropriate and cost-effective monitoring programmes that adequately capture the responses of fisheries to climate change have been elusive. The coastal waters of central and northern Namibia are a global hotspot of o...

Atractoscion macrolepis was described as a species separate to A. aequidens, distinguished by a geographically-separated distribution, genetic evidence and a diagnostic meristic character: the number of pored lateral line scales. However, the distinction of these species and description of A. macrolepis were based on the examination of a limited nu...

Catch‐and‐release (C&R) angling has grown in popularity due to increasing numbers of conservation‐minded anglers and regulations of recreational fisheries. C&R is often assumed to cause low mortality but can cause physiological and physical impairment. Fish metabolism and temperature interact to play a critical role in the biological functioning of...

1. Over recent decades, our understanding of climate change has accelerated greatly, but unfortunately, observable impacts have increased in tandem. Both mitigation and adaptation have not progressed at the level or scale warranted by our collective knowledge on climate change. More effective approaches to engage people on current and future anthro...

Genomic information can aid in the establishment of sustainable management plans for commercially exploited marine fishes, aiding in the long-term conservation of these resources. The southern African hakes (Merluccius capensis and M. paradoxus) are commercially valuable demersal fishes with similar distribution ranges but exhibiting contrasting li...

Anthropogenic-induced climate change is having profound impacts on aquatic ecosystems, and the resilience of fish populations will be determined by their response to these impacts. The northern Namibian coast is an ocean warming hotspot, with temperatures rising faster than the global average. The rapid warming in Namibia has had considerable impac...

Integrative and proactive conservation approaches are critical to the long-term persistence of biodiversity. Molecular data can provide important information on evolutionary processes necessary for conserving multiple levels of biodiversity (genes, populations, species, and ecosystems). However, molecular data are rarely used to guide spatial conse...

Shallow-water hake (Merluccius capensis) is a valuable demersal resource distributed throughout the Benguela Current region, from southern Angola to eastern South Africa. Previous molecular work revealed distinct populations confined to the northern and southern Benguela sub-systems, with asymmetrical migratory patterns. Here, we re-evaluated the g...

Over the last century, many shark populations have declined, primarily due to overexploitation in commercial, artisanal and recreational fisheries. In addition, in some locations the use of shark control programs also has had an impact on shark numbers. Still, there is a general perception that populations of large ocean predators cover wide areas...

Targeted sequencing is an increasingly popular Next Generation Sequencing (NGS) approach for studying populations that involves focusing sequencing efforts on specific parts of the genome of a species of interest. Methodologies and tools for designing targeted baits are scarce but in high demand. Here, we present specific guidelines and considerati...

Aim Intraspecific diversity is a significant component of adaptive potential, and thus, it is important to identify the evolutionary processes that have and will continue to shape the molecular diversity of natural populations. This study aims to untangle the possible drivers of intraspecific molecular diversity by testing whether patterns of histo...

Targeted sequencing is an increasingly popular Next Generation Sequencing (NGS) approach for studying populations, through focusing sequencing efforts on specific parts of the genome of a species of interest. Methodologies and tools for designing targeted baits are scarce but in high demand. Here, we present specific guidelines and considerations f...

Characterising and predicting species responses to anthropogenic global change is one of the key challenges in contemporary ecology and conservation. The sensitivity of marine species to climate change is increasingly being described with forecasted species distributions, yet these rarely account for population level processes such as genomic varia...

Over the last century, many populations of sharks have been reduced in numbers by overexploitation or attempts to mitigate human-shark interactions. Still, there is a general perception that populations of large ocean predators cover wide areas and therefore their diversity is less susceptible to local anthropogenic disturbance. Here we report retr...

Designing marine protected area (MPA) networks has relied primarily on species- or habitat-based measures that assess spatial distributions of biodiversity. Molecular and functional data have the potential to unlock information regarding the evolutionary uniqueness and resilience of natural communities, making phylogenetic diversity (PD) and functi...

Kingklip, Genypterus capensis, is a valuable fish resource in southern African waters, with a wide geographic distribution spanning South Africa and Namibia. Previous studies have provided evidence for multiple stocks in South Africa, but the extent of stock structuring across the southern Africa region remains unclear. In this study we genotyped o...

Background: As global change and anthropogenic pressures continue to increase, conservation and management increasingly needs to consider species' potential to adapt to novel environmental conditions. Therefore, it is imperative to characterise the main selective forces acting on ecosystems, and how these may influence the evolutionary potential o...

Emerging global change stressors have underlined the importance of informing conservation decisions with molecular diversity, particularly including intraspecific adaptive or evolutionary potential across species and populations. Population-level evolutionary potential is best captured by genomic approaches, yet these data types mostly remain limit...

Background: As global change and anthropogenic pressures continue to increase, conservation and management increasingly needs to consider species’ potential to adapt to novel environmental conditions. Therefore, it is imperative to characterise the main selective forces acting on ecosystems, and how these may influence the evolutionary potential of...

Background: As global change and anthropogenic pressures continue to increase, conservation and management increasingly needs to consider species’ potential to adapt to novel environmental conditions. Therefore, it is imperative to characterise the main selective forces acting on ecosystems, and how these may influence the evolutionary potential of...

Background: As global change and anthropogenic pressures continue to increase, conservation and management increasingly needs to consider species’ potential to adapt to novel environmental conditions. Therefore, it is imperative to characterise the main selective forces acting on ecosystems, and how these may influence the evolutionary potential of...

Genomic signatures associated with population divergence, speciation and the evolutionary mechanisms responsible for these are key research topics in evolutionary biology. Evolutionary radiations and parallel evolution have offered opportunities to study the role of the environment by providing replicates of ecologically driven speciation. Here, we...

Understanding the demographic history of introduced populations is essential for unravelling their invasive potential and adaptability to a novel environment. To this end, levels of genetic diversity within the native and invasive range of a species are often compared. Most studies, however, focus solely on contemporary samples, relying heavily on...

Gallet et al. (2018) studied the effect of two selection regimes on the maintenance of polymorphism in experimental populations. They took two strains of Escherichia coli, each resistant to a different antibiotic, evolved them in culture conditions representing “soft” or “hard” selective regimes, and measured polymorphism levels for three to five t...

Introgressive hybridization between Micropterus dolomieu and Micropterus salmoides was assessed in their invaded South African range using nine microsatellite markers and two mtDNA gene regions. Although M. dolomieu and M. salmoides are distantly related, indicated by the large uncorrected pairwise distances observed between the two species, mitoch...

Background: Genomic tools are increasingly being used on non-model organisms to provide insights into population structure and variability, including signals of selection. However, most studies are carried out in regions with distinct environmental gradients or across large geographical areas, in which local adaptation is expected to occur. Theref...

Fishes belonging to the family Clinidae in South Africa display super-embryonation, a rare reproductive mode were females gestate broods at different gestational stages, but little is known regarding the mating systems of this family. Here we tested the hypothesis that multiple males would contribute not only to the offspring of each female, but th...

The West Coast dusky kob Argyrosomus coronus is a commercially exploited fish with a distribution confined to the Angola–Benguela Frontal Zone (ABFZ) of the southeastern Atlantic Ocean. A previous study revealed that during a recent period of local warming the species extended its distribution into Namibian waters, where it hybridised with the resi...

Understanding the demographic history of introduced populations is essential for unravelling their invasive potential and adaptability to a novel environment. To this end, levels of genetic diversity within the native and invasive range of a species are often compared. Most studies, however, focus solely on contemporary samples, relying heavily on...

Irion et al. (2017; Mar Ecol Prog Ser 577:251-255) disputed the population estimates of white sharks Carcharodon carcharias along the South African coastline as presented in Andreotti et al. (2016; Mar Ecol Prog Ser 552:241-253), claiming that both the genetic and the capture-markrecapture results are poorly supported by the methods and data provid...

The growing threats to biodiversity and global alteration of habitats and species distributions make it increasingly necessary to consider evolutionary patterns in conservation decision-making. Yet there is no clear-cut guidance on how genetic features can be incorporated into conservation planning processes, with multiple molecular markers and sev...

Environmental gradients have been shown to disrupt gene flow in marine species, yet their influence in structuring populations at depth remains poorly understood. The Cape hakes (Merluccius paradoxus and M. capensis) are demersal species co-occurring in the Benguela Current system, where decades of intense fishing resulted in severely depleted stoc...

Aim The Benguela Upwelling System ( BUS ) is a major biogeographical boundary in the south‐eastern Atlantic, but little is known of the effect of historical permeability of the barrier on species distributed across the region. We used phylogenetic, life‐history and morphological analyses to test the influence of regional oceanographic features on g...

The loss of apex marine predators has been reported to have a cascade of detrimental effects on marine ecosystems; however, the general lack of empirical data can severely limit our understanding of the ecological interactions among marine species. In this study we propose an integrated approach using mark-recapture and genetic techniques to assess...

In the marine environment, an increasing number of studies have documented introgression and hybridization using genetic markers. Hybridization appears to occur preferentially between sister-species, with the probability of introgression decreasing with an increase in evolutionary divergence. Exceptions to this pattern were reported for the Cape ha...

Annex 3 Supporting references for Table S1.

Showing the genetic identification of samples Identification of M. capensis (white) and M. paradoxus (grey) based on the CR of mtDNA (A) and genotype frequencies as obtained in STRUCTURE for nine microsatellite loci (B).

Annex 1 Papers reviewed on the subject of hybridization between marine species, with information on species, genetic relationships and divergence levels between hybridizing species, genetic marker used and clustering methods employed to describe hybrids.

Microsatellite database Microsatellite database for M. capensis and M. paradoxus

Depicting the distribution of allelic frequencies for M. capensis and M. paradoxus Distribution of allelic frequencies of M. capensis (white) and M. paradoxus (grey) by microsatellite locus.

Annex 2 Merluccius capensis and M. paradoxus individuals identified as hybrids based on nine microsatellite loci (I), eight microsatellite loci (II) and six microsatellite loci (III): C—M. capensis, P—M paradoxus, F2—second generation hybrid, BcP—backcross with M. paradoxus. Individuals labelled as per Fig. 1.

Aim To determine the genetic structure of the white shark population around the South African coastline and, by including data from animals sampled elsewhere in the world, to provide new insights into white shark evolution at the global scale. Methods Mitochondrial and microsatellite analyses were performed on 302 free‐ranging white sharks collect...

Abstract In this paper, we analyzed the phylogeny of the section Bulbocodii (genus Narcissus; Amarillydaceae) using the matK and trnL-F fragments of cpDNA in order to review the validity of the recognized taxa. Our results indicate that Narcissus obesus should be considered a valid species, and that N. blancoi is a distinct taxon. In addition, seve...

The Benguela Current is considered to be a major biogeographic barrier for tropical and warm-temperate marine fish, but there is limited knowledge regarding its influence on population sub-structuring of in more cold-tolerant species. Employing genetic variation within the mitochondrial DNA Control Region and six cross-specific nuclear microsatelli...

Despite increasing awareness of large-scale climate-driven distribution shifts in the marine environment, no study has linked rapid ocean warming to a shift in distribution and consequent hybridization of a marine fish species. This study describes rapid warming (0.8°C/decade) in the coastal waters of the Angola-Benguela Frontal Zone over the last...

Contemporary patterns of genetic diversity and population connectivity within species can be influenced by both historical and contemporary barriers to gene flow. In the marine environment, present day oceanographic features such as currents, fronts and upwelling systems can influence dispersal of eggs/larvae and/juveniles/adults, shaping populatio...

Lichia amia is an important coastal recreational fishery species with a cosmopolitan distribution in the eastern Atlantic. In southern Africa, it is distributed from southern Angola to northern KwaZulu-Natal in South Africa. A recent biological survey revealed differences between Angolan and South African individuals suggesting that they may repres...

Geelbeck (Atractoscion aequidens) represents a valuable fishery resource in the Benguela Current region in southwestern Africa. Due to overexploitation the species is considered depleted in South Africa, and little information is available for the rest of its distribution in the region. Genetic studies of the species are essential to inform managem...

Freshwater species with small distribution ranges are vulnerable to extinction, especially when they exhibit small effective population sizes. Squalius torgalensis, Cyprinidae, is an endemic critically endangered fish species from southwestern Portugal, confined to the intermittent streams of the Mira drainage. Assessment of genetic diversity and p...

Isolation by distance analysis for the microsatellite dataset. Mantel test comparing minimal river geographic distance (km) with genetic differentiation (FST/(1 − FST)) among pairs of samples .

Isolation by distance analysis for the cyt b dataset. Mantel test comparing minimal river geographic distance (km) with genetic differentiation (FST/(1 − FST)) among pairs of samples

The West Coast dusky kob Argyrosomus coronus is an understudied yet important fishery species in Angola. During a five-year study (2005–2009), the species was recorded in all fishery sectors, but was most important in the inshore recreational fishery in southern Angola (Cunene Estuary to Namibe). Early juveniles (<300 mm total length, TL) were capt...