• Investing in Blue Natural Capital to Secure a Future for the Red Sea Ecosystems

      Cziesielski, Maha J.; Duarte, Carlos M.; Aalismail, Nojood; Al-Hafedh, Yousef; Anton, Andrea; Baalkhuyur, Faiyah; Baker, Andrew C.; Balke, Thorsten; Baums, Iliana B.; Berumen, Michael; et al. (Frontiers Media SA, 2021-01-15)
      For millennia, coastal and marine ecosystems have adapted and flourished in the Red Sea’s unique environment. Surrounded by deserts on all sides, the Red Sea is subjected to high dust inputs and receives very little freshwater input, and so harbors a high salinity. Coral reefs, seagrass meadows, and mangroves flourish in this environment and provide socio-economic and environmental benefits to the bordering coastlines and countries. Interestingly, while coral reef ecosystems are currently experiencing rapid decline on a global scale, those in the Red Sea appear to be in relatively better shape. That said, they are certainly not immune to the stressors that cause degradation, such as increasing ocean temperature, acidification and pollution. In many regions, ecosystems are already severely deteriorating and are further threatened by increasing population pressure and large coastal development projects. Degradation of these marine habitats will lead to environmental costs, as well as significant economic losses. Therefore, it will result in a missed opportunity for the bordering countries to develop a sustainable blue economy and integrate innovative nature-based solutions. Recognizing that securing the Red Sea ecosystems’ future must occur in synergy with continued social and economic growth, we developed an action plan for the conservation, restoration, and growth of marine environments of the Red Sea. We then investigated the level of resources for financial and economic investment that may incentivize these activities. This study presents a set of commercially viable financial investment strategies, ecological innovations, and sustainable development opportunities, which can, if implemented strategically, help ensure long-term economic benefits while promoting environmental conservation. We make a case for investing in blue natural capital and propose a strategic development model that relies on maintaining the health of natural ecosystems to safeguard the Red Sea’s sustainable development.
    • Climate change impact and adaptation: Lagoonal fishing communities in west Africa

      Davies-Vollum, K. Siân; Raha, Debadayita; Koomson, Daniel; University of Derby (Springer, 2021-01-08)
      Lagoons are a common feature of the low-lying West African coastline. These lagoons are resource-rich and biodiverse. The small-scale fishing communities, which border them, are dependent on the resources and ecosystem services for their livelihoods and well-being. Climate change has had significant and diverse effects on both the lagoons and their surrounding communities. Sea level rise has caused erosion of the coast and increased the risk of floods. Changes to rainfall patterns have caused shifts in lagoon ecosystems and physical cycles. Of particular relevance to lagoon fishing communities is the fluctuation in quantity and distribution of fish catch that they rely upon for economic livelihood. Understanding the vulnerability of these communities to the effects of climate change is critical to supporting and developing successful adaptations. Using a case study from Ghana, sustainable livelihoods approach (SLA) and vulnerability framework are used to characterize the community vulnerability, giving insight into the temporal and spatial dynamics of vulnerability and how subsections of the community may be identified and prioritized for adaptation interventions. A scalar analysis of the relevant coastal and environmental frameworks and policy to support climate change adaptation in coastal communities reveals the common challenges in implementing adaptation interventions and strategies in the region. A policy gap exists between high level, institutional coastal, and climate directives and implementation of climate adaptations at the local level. That gap might be bridged by a participatory approach that places coastal communities at the center of creating and enacting climate change adaptations.
    • Seasonality, DNA degradation and spatial heterogeneity as drivers of eDNA detection dynamics

      Troth, Christopher R.; Sweet, Michael J.; Nightingale, Jen; Burian, Alfred; University of Derby; SureScreen Scientifics Ltd, Morley; Bristol Zoological Society, Clifton, Bristol; University of Bristol; Lurio University, Nampula, Mozambique (Elsevier, 2021-01-06)
      In recent years, eDNA-based assessments have evolved as valuable tools for research and conservation. Most eDNA-based applications rely on comparisons across time or space. However, temporal, and spatial dynamics of eDNA concentrations are shaped by various drivers that can affect the reliability of such comparative approaches. Here, we assessed (i) seasonal variability, (ii) degradation rates and (iii) micro-habitat heterogeneity of eDNA concentrations as key factors likely to inflict uncertainty in across site and time comparisons. In a controlled mesocosm experiment, using the white-clawed crayfish as a model organism, we found detection probabilities of technical replicates to vary substantially and range from as little as 20 to upwards of 80% between seasons. Further, degradation rates of crayfish eDNA were low and target eDNA was still detectable 14–21 days after the removal of crayfish. Finally, we recorded substantial small-scale in-situ heterogeneity and large variability among sampling sites in a single pond of merely 1000m2 in size. Consequently, all three tested drivers of spatial and temporal variation have the potential to severely impact the reliability of eDNA-based site comparisons and need to be accounted for in sampling design and data analysis of field-based applications.
    • Climate Change Adaptation in West Africa: A critical analysis of climate change adaptation policies and their implications for coastal communities in West Africa

      Backler, Scott; University of Derby (University of Derby, 2021)
      The UNFCCC, (2019) identifies climate change as a “threat multiplier” meaning that a sizeable amount of the UNs 17 Sustainable Development Goals are at threat from climate change. The recently published sixth assessment report by the IPCC further highlights that climate change is now at some level an unavoidable reality (IPCC, 2021). Whilst many West African coastal countries have adaptation framework to respond to the threat of climate change, several studies have highlighted an apparent gap in policy implementation, meaning that the policies are not as effective as intended at a grassroots level (Boateng, 2018; Davies-Vollum, Raha, and Koomson, 2021). Aims: 1. To critically analyse the institutional and organisational structure of climate change adaptation (CCA) policies and strategies in West African Coastal Countries. 2. To evaluate socio-cultural or socio-economic issues influencing policy implementation at a grassroots level. 3. To recommend alternative systematic policies or practical processes that could enable successful implementation of climate change adaption plans. Academic supervisors for this project - Dr Debadayita Raha & Dr Sian Davies-Vollum.
    • Zircon geochronological and geochemical insights into pluton building and volcanic-hypabyssal-plutonic connections: Oki-Dōzen, Sea of Japan - a complex intraplate alkaline volcano

      Scarrow, Jane; Chamberlain, Katy J.; Montero, Pilar; Horstwood, Matthew S.A.; Kimura, Jun-Ichi; Tamura, Yoshihiko; Chang, Qing; Barclay, Jenni; University of Granada, Campus Fuentenueva, Granada, Spain; University of East Anglia; et al. (Mineralogical Society of America, 2021)
      The relationship between plutonic and volcanic components of magmatic plumbing systems continues to be a question of intense debate. The Oki-Dōzen Islands, Sea of Japan, preserve outcrops of temporally-associated plutonic, hypabyssal and volcanic rocks. Juxtaposition of these, by post-intrusion uplift, placed Miocene syenites in inferred faulted contact with volcanic trachytes that are cut by rhyolite hypabyssal dikes. This provides a window deep into the timing and origins of magma storage architecture and dynamics. Our aim is to determine what the age and composition of zircon, which is ubiquitous in all samples, can reveal about the plutonic-volcanic connection. Here we show magma source characteristics are recorded in zircon Hf isotopes whereas, in addition to source composition, differentiation processes - assimilation of heterogeneous hydrothermally altered crust and extensive fractional crystallization - are preserved in zircon O isotopes and trace elements, respectively. Combined with new U-Th-Pb SHRIMP zircon ages, 6.4–5.7 Ma, the compositional data show pluton formation was by protracted amalgamation of discrete magma pulses. The rhyolite dike preserves an evolved fraction segregated from these. Synchronous with plutonism was volcanic eruption of trachyte magma derived from the same source, but apparently stalled at a relatively shallow depth. Stalling occurred at least above the zone of amphibole stability since amphibole-compatible Sc and Ti were not depleted in the trachyte melt - resulting in elevated values of these in the volcanic, compared to the plutonic, zircon. Identifying smaller episodic magma pulses in a larger magmatic complex places constraints on potential magma fluxes and eruptible volumes. Distinct from high-flux, large volume, plume-related ocean islands with extensive vertically distributed multi-stage magmatic reservoirs or subduction-related transcrustal magma reservoirs, Oki-Dōzen was a low-flux system with incremental pluton growth and small- to moderate-scale eruptions.
    • Fundamental questions and applications of sclerochronology: Community-defined research priorities.

      Trofimova, Tamara; Alexandroff, Stella; Mette, Madelyn; Tray, Elizabeth; Butler, Paul; Campana, Steven; Harper, Elizabeth; Johnson, Andrew; Morrongiello, John; Peharda, Melita; et al. (Elsevier, 2020-09-09)
      Horizon scanning is an increasingly common strategy to identify key research needs and frame future agendas in science. Here, we present the results of the first such exercise for the field of sclerochronology, thereby providing an overview of persistent and emergent research questions that should be addressed by future studies. Through online correspondence following the 5th International Sclerochronology Conference in 2019, participants submitted and rated questions that addressed either knowledge gaps or promising applications of sclerochronology. An initial list of 130 questions was compiled based on contributions of conference attendees and reviewed by expert panels formed during the conference. Herein, we present and discuss the 50 questions rated to be of the highest priority, determined through an online survey distributed to sclerochronology community members post the conference. The final list (1) includes important questions related to mechanisms of biological control over biomineralization, (2) highlights state of the art applications of sclerochronological methods and data for solving long-standing questions in other fields such as climate science and ecology, and (3) emphasizesthe need for common standards for data management and analysis. Although research priorities are continually reassessed, our list provides a roadmap that can be used to motivate research efforts and advance sclerochronology towardnew, and more powerful, applications.
    • Growth-increment characteristics and isotopic (δ18O) temperature record of sub-thermocline Aequipecten opercularis (Mollusca:Bivalvia): evidence from modern Adriatic forms and an application to early Pliocene examples from eastern England.

      Johnson, Andrew; Valentine, Annemarie; Schöne, Bernd; Leng, Melanie; Sloane, Hilary; Janekovic, Ivica; University of Derby; Nottingham Trent University; University of Mainz, 55128 Mainz, Germany; National Environmental Isotope Facility, British Geological Survey, Keyworth; et al. (Elsevier, 2020-09-02)
      The shell δ18O of young modern Aequipecten opercularis from the southern North Sea provides an essentially faithful record of seasonal variation in seafloor temperature. In this well-mixed setting, A. opercularis shell δ18O also serves as a proxy for seasonal variation in surface temperature. Individuals from less agitated (e.g. deeper) settings in a warm climate would not be expected to record the full seasonal range in surface temperature because of thermal stratification in summer. Such circumstances have been invoked to explain cool isotopic summer temperatures from early Pliocene A. opercularis of eastern England. Support for a sub-thermocline setting derives from high-amplitude variation in microgrowth-increment size, which resembles the pattern in sub-thermocline A. opercularis from the southern Mediterranean Sea. Here, we present isotope and increment profiles from further sub-thermocline individuals, live-collected from a location in the Adriatic Sea for which we provide modelled values of expected shell δ18O. We also present data from supra-thermocline shells from the English Channel and French Mediterranean coast. The great majority of sub-thermocline A. opercularis show high-amplitude variation in increment size, and winter and summer δ18O values are generally quite close to expectation. However, the relatively warm summer conditions of 2015 are not recorded, in most cases due to a break in growth, perhaps caused by hypoxia. The supra-thermocline shells show subdued increment variation and yield isotopic winter and summer temperatures quite close to the local directly measured values. A. opercularis shells therefore provide a fairly good isotopic record of ambient temperature (if not always of relatively warm summer conditions below the thermocline) and their hydrographic setting can be determined from increment data. Early Pliocene examples from eastern England can be interpreted as having lived in a setting below the thermocline, with a higher seasonal range in surface temperature than now in the adjacent southern North Sea.
    • Development and application of eDNA-based tools for the conservation of white-clawed crayfish

      Troth, Christopher R.; Burian, Alfred; Mauvisseau, Quentin; Bulling, Mark; Nightingale, Jen; Mauvisseau, Christophe; Sweet, Michael J.; University of Derby; University of Bristol; Fédération de Pêche et de Protection du Milieu Aquatique du Loir-et-Cher, France (Elsevier, 2020-07-30)
      eDNA-based methods represent non-invasive and cost-effective approaches for species monitoring and their application as a conservation tool has rapidly increased within the last decade. Currently, they are primarily used to determine the presence/absence of invasive, endangered or commercially important species, but they also hold potential to contribute to an improved understanding of the ecological interactions that drive species distributions. However, this next step of eDNA-based applications requires a thorough method development. We developed an eDNA assay for the white-clawed crayfish (Austropotamobius pallipes), a flagship species of conservation in the UK and Western Europe. Multiple subsequent in-situ and ex-situ validation tests aimed at improving method performance allowed us to apply eDNA-based surveys to evaluate interactions between white-clawed crayfish, crayfish plague and invasive signal crayfish. The assay performed well in terms of specificity (no detection of non-target DNA) and sensitivity, which was higher compared to traditional methods (in this case torching). The eDNA-based quantification of species biomass was, however, less reliable. Comparison of eDNA sampling methods (precipitation vs. various filtration approaches) revealed that optimal sampling method differed across environments and might depend on inhibitor concentrations. Finally, we applied our methodology together with established assays for crayfish plague and the invasive signal crayfish, demonstrating their significant interactions in a UK river system. Our analysis highlights the importance of thorough methodological development of eDNA-based assays. Only a critical evaluation of methodological strengths and weaknesses will allow us to capitalise on the full potential of eDNA-based methods and use them as decision support tools in environmental monitoring and conservation practice.
    • Characterising the vulnerability of fishing households to climate and environmental change: Insights from Ghana

      Koomson, Daniel; Davies-Vollum, K. Siân; Raha, Debadayita; University of Derby (Elseiver, 2020-07-27)
      Rural coastal communities in the global south are mostly natural resource-dependent and their livelihoods are therefore vulnerable to the impacts of climate and environmental changes. Efforts to improve their adaptive capacity often prove mal-adaptive due to misunderstanding the dynamics of the unique socioeconomic factors that shape their vulnerability. By integrating theories from climate change vulnerability and the Sustainable Livelihoods Approach, this study draws upon household survey data from a fishing community in Ghana to assess the vulnerability of fishing households to climate change and explore how their vulnerability is differentiated within the community. The findings suggest that household incomes in the last decade have reduced significantly, attributable to an interaction of both climatic and non-climatic factors. Analysis of the characteristics of three vulnerability groups derived by quantile clustering showed that the most vulnerable household group is not necessarily women or poorer households as expected. Rather, it is dynamic and includes all gender and economic class categories in varying proportions depending on the success or failure of the fishing season. The findings suggest furthermore that the factors that significantly differentiates vulnerability between households differ, depending on whether households are categorised by economic class, gender of household-head or vulnerability group. Consequently, the study highlights the importance of looking beyond existing social categorizations like gender and economic classes when identifying and prioritizing households for climate change adaptive capacity building.
    • Rapid assembly of high-Mg andesites and dacites by magma mixing at a continental arc stratovolcano

      Conway, Chris; Chamberlain, Katy J.; Harigane, Yumiko; Morgan, Daniel; Wilson, Colin; Research Institute of Earthquake and Volcano Geology, Japan; National Museum of Nature and Science, Japan; University of Derby; University of Leeds; Victoria University of Wellington (The Geological Society of America, 2020-06-25)
      Studies of pre-eruptive processes at active volcanoes require precise petrochronological constraints if they are to contribute to hazard assessment during future eruption events. We present petrological and geochemical data, and orthopyroxene diffusion timescales for samples from late Pleistocene high-Mg andesite dacite lavas (Mg#53–69) at Ruapehu volcano, New Zealand, as a case study of rapid magma genesis and eruption at a continental arc stratovolcano. Assembly of Ruapehu high-Mg magmas involved the mixing of primitive magmas plus entrained mantle equilibrated olivines with mid-crustal felsic mush bodies, yielding hybridized magmas with ubiquitous pyroxene reverse-zoning patterns. Orthopyroxene Fe-Mg interdiffusion timescales linked to quantitative crystal orientation data show that most lavas erupted <10 days after resumption of crystal growth following magma mixing events. The eruption of lavas within days of mixing events implies that pre-eruptive warnings may be correspondingly short.
    • The potential of fatty acid isotopes to trace trophic transfer in aquatic food-webs

      Burian, Alfred; Nielsen, Jens M.; Hansen, Thomas; Bermudez, Rafael; Winder, Monika; University of Derby; Stockholm University; Helmholtz Centre for Ocean Research Kiel (GEOMAR), Kiel, Germany; Escuela Superior Politécnica del Litoral, ESPOL, Guayaquil, Ecuador (The Royal Society, 2020-06-15)
      Compound-specific isotope analyses (CSIA) of fatty acids (FA) constitute a promising tool for tracing energy flows in food-webs. However, past applications of FA-specific carbon isotope analyses have been restricted to a relatively coarse food-source separation and mainly quantified dietary contributions from different habitats. Our aim was to evaluate the potential of FA-CSIA to provide high-resolution data on within-system energy flows using algae and zooplankton as model organisms. First, we investigated the power of FA-CSIA to distinguish among four different algae groups, namely cyanobacteria, chlorophytes, haptophytes and diatoms. We found substantial within-group variation but also demonstrated that δ13C of several FA (e.g. 18:3ω3 or 18:4ω3) differed among taxa, resulting in group-specific isotopic fingerprints. Second, we assessed changes in FA isotope ratios with trophic transfer. Isotope fractionation was highly variable in daphnids and rotifers exposed to different food sources. Only δ13C of nutritionally valuable poly-unsaturated FA remained relatively constant, highlighting their potential as dietary tracers. The variability in fractionation was partly driven by the identity of food sources. Such systematic effects likely reflect the impact of dietary quality on consumers' metabolism and suggest that FA isotopes could be useful nutritional indicators in the field. Overall, our results reveal that the variability of FA isotope ratios provides a substantial challenge, but that FA-CSIA nevertheless have several promising applications in food-web ecology. This article is part of the theme issue ‘The next horizons for lipids as ‘trophic biomarkers’: evidence and significance of consumer modification of dietary fatty acids’.
    • Editorial: Coral Reefs in the Anthropocene – Reflecting on 20 Years of Reef Conservation UK

      Andradi-Brown, Dominic A.; Banaszak, Anastazia T.; Frazer, Thomas K.; Gilchrist, Hannah; Harborne, Alastair R.; Head, Catherine E. I.; Koldewey, Heather J.; Levy, Emma; Richards, Kirsty; Short, Rebecca; et al. (Frontiers Media SA, 2020-06-12)
      Editorial on the Research Topic Coral Reefs in the Anthropocene – Reflecting on 20 Years of Reef Conservation UK.
    • Deep and disturbed: conditions for formation and eruption of a mingled rhyolite at Ascension Island, south Atlantic

      Chamberlain, Katy J.; Barclay, Jenni; Preece, Katie; Brown, Richard J.; McIntosh, Iona; EIMF; University of Derby; University of East Anglia; Swansea University; Durham University; et al. (Presses universitaires de Strasbourg, 2020-05-05)
      The generation of felsic melts (through open or closed system processes) within ocean island volcanoes has been a key area of study since their identification. At Ascension Island in the south Atlantic, explosively erupted felsic melts have, to date, demonstrated a marked absence of signs of magma mixing and crustal assimilation. Here we present the first observations of a fall deposit from Ascension Island recording both macro- and micro-scale evidence for magma mingling. Geochemical analyses of mineral and glass phases, coupled with volatile concentrations of melt inclusions highlight the role of lower-crustal partial melting to produce rhyolitic magmas. Glass textures and the lack of zoning in major mineral phases indicate that mingling with a mafic melt occurred shortly prior to eruption. These inferences of a deep rhyolite production zone, coupled with rapid ascent rates highlight the challenges in forecasting a similar style of eruption at Ascension Island in the future.
    • Completing the life cycle of a broadcast spawning coral in a closed mesocosm

      Craggs, Jamie; Guest, James; Davis, Michelle; Sweet, Michael; University of Derby; Newcastle University; Horniman Museum and Gardens, London (Informa UK Limited, 2020-04-28)
      Studies of broadcast spawning in corals are fundamental to our understanding of early life history characteristics, reproductive biology, restoration etc. Spawning of corals for research is routinely conducted, but this is mostly restricted to sites adjacent to reefs and from broodstock collected from the wild just prior to gamete release. Only recently has it been possible to induce predictable broadcast spawning in an ex situ environment, and nobody has successfully closed the life cycle (i.e., production of an F2 generation) of these corals. Here, for the first time, we closed the life cycle of the broadcast spawning coral Acropora millepora in a fully closed ex situ mesocosm. This breakthrough has numerous implications for our understanding of reproductive biology, specifically it offers potential to deepen our understanding of the genetic influence on adaptive traits such as heat tolerance, growth and disease resistance over multiple generations.
    • Tracing the origin of olive ridley turtles entangled in ghost nets in the Maldives: A phylogeographic assessment of populations at risk

      Stelfox, Martin; Burian, Alfred; Shanker, Kartik; Rees, Alan F.; Jean, Claire; Willson, Maïa S.; Manik, Nashwa Ahmed; Sweet, Michael; University of Derby; Olive Ridley Project, 11 Dane Close, Bramhall, Stockport, Cheshire; et al. (Elsevier BV, 2020-04-07)
      Abandoned, lost or discarded fishing nets, (ghost nets) represent a major threat to marine vertebrates. However, thorough assessments of their impact on threatened species are largely missing. In the Maldives, olive ridley sea turtles (Lepidochelys olivacea) are frequently caught in ghost nets however the archipelago does not support a significant nesting population. Our aim in this study was to determine the origin of olive ridleys entangled in ghost nets found in the Maldives and evaluate potential impacts on respective source populations. Based on a citizen science and conservation program, we recorded 132 olive ridley turtles entangled in ghost nets in just one year. Genetic analyses (mtDNA) of entangled individuals and of potential source populations revealed that most captured olive ridleys originated from Sri Lanka and eastern India. Oman could be excluded as source population, even during the prevalence of the south west monsoon. Based on our results and already available published literature, we were able to estimate that the recorded ghost net entanglements accounted for a relatively small amount (0.48%) of the eastern Indian population. However, the entangled turtles accounted for a much larger percentage (41%) of the Sri Lankan populations. However, it should be noted that our estimates of population-level mortality are linked to substantial uncertainty due to the lack of reliable information on population dynamics. Consequently, any precautionary protection measures applied should be complemented with improved quantification of turtle recruitment and life-stage specific mortalities.
    • Heat waves are a major threat to turbid coral reefs in Brazil

      Duarte, Gustavo A. S.; Villela, Helena D. M.; Deocleciano, Matheus; Silva, Denise; Barno, Adam; Cardoso, Pedro M.; Vilela, Caren L. S.; Rosado, Phillipe; Messias, Camila S. M. A.; Chacon, Maria Alejandra; et al. (Frontiers Media SA, 2020-03-30)
      Coral reefs are threatened by climate change on a global scale with thermal stress events and mass coral bleaching being widely reported. The reefs off the east coast of Brazil (and other turbid areas) have, however, historically escaped such thermal stress events, with relatively low levels of background coral mortality (5–10%). This has recently changed. Here we show that, in 2019, degree heating weeks (DHW) of 19.65 coincided with catastrophic declines in coral cover, especially in the major reef building hydrocoral Millepora alcicornis. The decline was due to bleaching associated with exposure to high temperature stress culminating in DHW values exceeding 15 for a period of 50 days. At two independent sites, surveys showed upwards of 83.5 ± 9.0 and 89.1 ± 3.9% mortality, and a third site showed relatively lower (albeit still high) mortality rates of 43.3 ± 12.0%. The mass die-off in 2019 is unprecedented in the South Atlantic reefs and coincides with increased heating events.
    • Estimating food production in an urban landscape

      Grafius, Darren R.; Edmondson, Jill L.; Norton, Briony A.; Clark, Rachel; Mears, Meghann; Leake, Jonathan R.; Corstanje, Ron; Harris, Jim A.; Warren, Philip H.; University of Sheffield; et al. (Springer Science and Business Media LLC, 2020-03-20)
      There is increasing interest in urban food production for reasons of food security, environmental sustainability, social and health benefits. In developed nations urban food growing is largely informal and localised, in gardens, allotments and public spaces, but we know little about the magnitude of this production. Here we couple own-grown crop yield data with garden and allotment areal surveys and urban fruit tree occurrence to provide one of the first estimates for current and potential food production in a UK urban setting. Current production is estimated to be sufficient to supply the urban population with fruit and vegetables for about 30 days per year, while the most optimistic model results suggest that existing land cultivated for food could supply over half of the annual demand. Our findings provide a baseline for current production whilst highlighting the potential for change under the scaling up of cultivation on existing land.
    • The evolution of pair-living, sexual monogamy, and cooperative infant care: Insights from research on wild owl monkeys, titis, sakis, and tamarins

      Fernandez-Duque, Eduardo; Huck, Maren; Van Belle, Sarie; Di Fiore, Anthony; University of Derby; Yale University; University of Austin, Texas (Wiley, 2020-03-19)
      “Monogamy” and pair bonding have long been of interest to anthropologists and primatologists. Their study contributes to our knowledge of human evolutionary biology and social evolution without the cultural trappings associated with studying human societies directly. Here, we first provide an overview of theoretical considerations, followed by an evaluation of recent comparative studies of the evolution of “social monogamy”; we are left with serious doubts about the conclusions of these studies that stem from the often poor quality of the data used and an overreliance on secondary sources without vetting the data therein. We then describe our field research program on four “monogamous” platyrrhines (owl monkeys, titis, sakis, and tamarins), evaluate how well our data support various hypotheses proposed to explain “monogamy,” and compare our data to those reported on the same genera in comparative studies. Overall, we found a distressing lack of agreement between the data used in comparative studies and data from the literature for the taxa that we work with. In the final section, we propose areas of research that deserve more attention. We stress the need for more high‐quality natural history data, and we urge researchers to be cautious about the uncritical use of variables of uncertain internal validity. Overall, it is imperative that biological anthropologists establish and follow clear criteria for comparing and combining results from published studies and that researchers, reviewers, and editors alike comply with these standards to improve the transparency, reproducibility, and interpretability of causal inferences made in comparative studies.
    • Reliable eDNA detection and quantification of the European weather loach (Misgurnus fossilis)

      Brys, Rein; Halfmaerten, David; Neyrinck, Sabrina; Mauvisseau, Quentin; Auwerx, Johan; Sweet, Michael; Mergeay, Joachim; Research Institute for Nature and Forest, Geraardsbergen, Belgium; University of Derby; SureScreen Scientifics Ltd (Wiley, 2020-03-10)
      The European weather loach (Misgurnus fossilis) is a cryptic and poorly known fish species of high conservation concern. The species is experiencing dramatic population collapses across its native range to the point of regional extinction. Although environmental DNA (eDNA)‐based approaches offer clear advantages over conventional field methods for monitoring rare and endangered species, accurate detection and quantification remain difficult and quality assessment is often poorly incorporated. In this study, we developed and validated a novel digital droplet PCR (ddPCR) eDNA‐based method for reliable detection and quantification, which allows accurate monitoring of M. fossilis across a number of habitat types. A dilution experiment under laboratory conditions allowed the definition of the limit of detection (LOD) and the limit of quantification (LOQ), which were set at concentrations of 0.07 and 0.14 copies μl–1, respectively. A series of aquarium experiments revealed a significant and positive relationship between the number of individuals and the eDNA concentration measured. During a 3 year survey (2017–2019), we assessed 96 locations for the presence of M. fossilis in Flanders (Belgium). eDNA analyses on these samples highlighted 45% positive detections of the species. On the basis of the eDNA concentration per litre of water, only 12 sites appeared to harbour relatively dense populations. The other 31 sites gave a relatively weak positive signal that was typically situated below the LOQ. Combining sample‐specific estimates of effective DNA quantity (Qe) and conventional field sampling, we concluded that each of these weak positive sites still likely harboured the species and therefore they do not represent false positives. Further, only seven of the classified negative samples warrant additional sampling as our analyses identified a substantial risk of false‐negative detections (i.e., type II errors) at these locations. Finally, we illustrated that ddPCR outcompetes conventional qPCR analyses, especially when target DNA concentrations are critically low, which could be attributed to a reduced sensitivity of ddPCR to inhibition effects, higher sample concentrations being accommodated and higher sensitivity obtained.
    • Minimum drift times infer trajectories of ghost nets found in the Maldives

      Stelfox, Martin; Lett, Christophe; Reid, Geraldine; Souch, Graham; Sweet, Michael; University of Derby; Olive Ridley Project, Bramhall, Stockport, Cheshire; MARBEC, IRD, Ifremer, Univ Montpellier, CNRS, Sète, France; National Museums Liverpool (Elsevier BV, 2020-03-07)
      This study explores methods to estimate minimum drift times of ghost nets found in the Maldives with the aim of identifying a putative origin. We highlight that percentage cover of biofouling organisms and capitulum length of Lepas anatifera are two methods that provide these estimates. Eight ghost nets were collected in the Maldives and estimated drift times ranged between 7.5 and 101 days. Additionally, Lagrangian simulations identified drift trajectories of 326 historical ghost nets records. Purse seine fisheries (associated with Korea, Mauritius, the Philippines, Spain, France and Seychelles) and gill nets from Sri Lanka were identified as 'high risk' fisheries with regard to likley origins of ghost nets drifting into the Maldives. These fisheries are active in areas where dense particle clusters occured (drift trajectories between 30 and 120 days). Interestingly, ghost nets drifting less than 30 days however, remained inside the exclusive economic zone of the Maldivian archipelago highlighting potential illegal, unreported and unregulated fishing activity is occuring in this area. This study therefore points to the urgent need for gear loss reporting to be undertaken, especially by purse seine and gill net fisheries in order to ascertain the source of this major threat to marine life. This should also be coupled with an improvment in the data focused on spatial distribution of the abandoned, lost or discarded fishing gear originating from both large- and small-scale fisheries.