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Management of deep-sea fisheries in areas beyond national jurisdiction by Regional Fisheries Management Organizations/Arrangements (RFMO/As) requires identification of areas with Vulnerable Marine Ecosystems (VMEs). Currently, fisheries data, including trawl and longline bycatch data, are used by many RFMO/As to inform the identification of VMEs. However, the collection of such data creates impacts and there is a need to collect non-invasive data for VME identification and monitoring purposes. Imagery data from scientific surveys satisfies this requirement, but there currently is no established framework for identifying VMEs from images. Thus, the goal of this study was to bring together a large international team to determine current VME assessment protocols and establish preliminary global consensus guidelines for identifying VMEs from images. An initial assessment showed a lack of consistency among RFMO/A regions regarding what is considered a VME indicator taxon, and hence variability in how VMEs might be defined. In certain cases, experts agreed that a VME could be identified from a single image, most often in areas of scleractinian reefs, dense octocoral gardens, multiple VME species' co-occurrence, and chemosynthetic ecosystems. A decision flow chart is presented that gives practical interpretation of the FAO criteria for single images. To further evaluate steps of the flow chart related to density, data were compiled to assess whether scientists perceived similar density thresholds across regions. The range of observed densities and the density values considered to be VMEs varied considerably by taxon, but in many cases, there was a statistical difference in what experts considered to be a VME compared to images not considered a VME. Further work is required to develop an areal extent index, to include a measure of confidence, and to increase our understanding of what levels of density and diversity correspond to key ecosystem functions for VME indicator taxa. Based on our results, the following recommendations are made: 1. There is a need to establish a global consensus on which taxa are VME indicators. 2. RFMO/As should consider adopting guidelines that use imagery surveys as an alternative (or complement) to using bycatch and trawl surveys for designating VMEs. 3. Imagery surveys should also be included in Impact Assessments. And 4. All industries that impact the seafloor, not just fisheries, should use imagery surveys to detect and identify VMEs.

Past responses to environmental change provide vital baseline data for estimating the potential resilience of extant taxa to future change. Here, we investigate the latitudinal range contraction that terrestrial and freshwater turtles (Testudinata) experienced from the Late Cretaceous to the Paleogene (100.5-23.03 mya) in response to major climatic changes. We apply ecological niche modeling (ENM) to reconstruct turtle niches, using ancient and modern distribution data, paleogeographic reconstructions, and the HadCM3L climate model to quantify their range shifts in the Cretaceous and late Eocene. We then use the insights provided by these models to infer their probable ecological responses to future climate scenarios at different representative concentration pathways (RCPs 4.5 and 8.5 for 2100), which project globally increased temperatures and spreading arid biomes at lower to mid-latitudes. We show that turtle ranges are predicted to expand poleward in the Northern Hemisphere, with decreased habitat suitability at lower latitudes, inverting a trend of latitudinal range contraction that has been prevalent since the Eocene. Trionychids and freshwater turtles can more easily track their niches than Testudinidae and other terrestrial groups. However, habitat destruction and fragmentation at higher latitudes will probably reduce the capability of turtles and tortoises to cope with future climate changes.

Warm-water coral reefs are facing unprecedented Anthropogenic driven threats to their continued existence as biodiverse, functional ecosystems upon which hundreds of millions of people rely. Determining the tipping point thresholds of coral reef ecosystems requires robust assessment of multiple stressors and their interactive effects. We draw upon a literature search and the recent Global Tipping Points Revision initiative to consider warm-water coral reef ecosystem tipping point threshold sensitivity. Considering observed and projected stressor impacts we recognise a global mean surface temperature (relative to pre-industrial) tipping point threshold of 1.2°C (range 0.7-1.5°C) and an atmospheric CO2 warming threshold of 350ppm (range 326-400 ppm), whilst acknowledging that interacting stressors, ocean warming response time, overshoot and cascading impacts have yet to be sufficiently assessed but are likely to lower this threshold. These uncertainties around tipping point sensitivities for such a crucially important ecosystem underlines the imperative of robust assessment and, in the case of knowledge gaps, employing a precautionary principle favouring the lower range tipping point values. [ABSTRACT FROM AUTHOR]

Species distribution modeling is a widely used technique for estimating the potential habitats of target organisms based on their environmental preferences. These methods serve as valuable tools for resource managers and conservationists, and their utilization is increasing, particularly in marine environments where data limitations persist as a challenge. In this study, we employed the global distribution predictions of six cold-water coral species as a case study to investigate various factors influencing predictions, including modeling algorithms, background points sampling strategies and sizes, and the collinearity of environmental datasets, using both discriminative and functional performance metrics. The choice of background sampling method exhibits a stronger influence on model performance compared to the effects of modeling algorithms, background point sampling size, and the collinearity of the environmental dataset. Predictions that utilize kernel density backgrounds, maintain an equal number of presences and background points for algorithms of BRT, RF, and MARS, and employ a substantial number of background points for MAXENT, coupled with a collinearity-filtered environmental dataset in species distribution modeling, yield higher levels of discriminative and functional performance. Overall, BRT and RF outperformed MAXENT, a conclusion that is further substantiated by the analysis of smoothed residuals and the uncertainty associated with the predicted habitat suitability of Madrepora oculata. This study offers valuable insights for enhancing species distribution modeling in marine benthic environments, thereby benefiting resource management and conservation strategies for benthic species. [ABSTRACT FROM AUTHOR]

The Big Seaweed Search invites people to survey UK seashores for 14 conspicuous seaweeds. The science investigates: (i) impact of sea temperature rise; (ii) spread of non‐native species; and (iii) impact of ocean acidification. Survey data submitted between June 2016 and May 2020 were analysed to evaluate and explore project directions in relation to citizen science project development.Of the 378 surveys submitted, 1,414 people participated, contributing 1,531 person hours. Surveys were undertaken around the UK, with the highest proportion (46.7%) in the south west and the lowest (3.7%) in the north east.After data verification, 1,007 (54%) records were accepted. Fucus serratus had the highest number of entries correctly identified (66%) and Undaria pinnatifida the lowest (5%), inferring that at least some seaweeds can be difficult to identify, although the overall misidentification rate was relatively low (c. 15%).Apart from Alaria esculenta, U. pinnatifida and Saccharina latissima, the large brown seaweeds were abundant on at least some shores. Non‐natives Sargassum muticum and Asparagopsis armata, were band‐forming but in low numbers. Coralline algae, whilst band‐forming on some shores, were most commonly patchy or sparse in abundance. Revisits, i.e. repeat surveys, at the same site with an interval of at least 1 year, are relatively low, with 18 sites revisited once and three sites revisited twice. Currently, data are insufficient to determine whether any changes in abundance could be detected.This study highlights areas where project developments can enhance data quality and quantity, e.g. better identification resources, training programmes for dedicated volunteers, and an annual focus week of activities. The project framed around climate change impacts, aims to raise awareness of the ecological importance of, and threats faced by, this understudied habitat and introduce conservation concepts including the need to protect common species showing signs of decline. [ABSTRACT FROM AUTHOR]

Understanding the spatial distribution of genetic diversity and its evolutionary history is an essential part of developing effective biodiversity management plans. This may be particularly true when considering the value of peripheral or disjunct populations. Although conservation decisions are often made with reference to geopolitical boundaries, many policymakers also consider global distributions, and therefore a species' global status may temper its regional status. Many disjunct populations can be found in the Great Lakes region of North America, including those of Bartonia paniculata subsp. paniculata, a species that has been designated as threatened in Canada but globally secure. We compared chloroplast sequences between disjunct (Canada) and core (USA) populations of B. paniculata subsp. paniculata separated by 600 km, which is the minimum distance between disjunct and core populations in this subspecies. We found that although lineages within the disjunct populations shared a relatively recent common ancestor, the genetic divergence between plants from Ontario and New Jersey was substantially greater than expected for a consubspecific comparison. A coalescence-based analysis dated the most recent common ancestor of the Canadian and US populations at approximately 534 000 years ago with the lower confidence estimate at 226 000 years ago. This substantially predates the Last Glacial Maximum and suggests that disjunct and core populations have followed independent evolutionary trajectories throughout multiple glacial-interglacial cycles. Our findings provide important insight into the diverse processes that have resulted in numerous disjunct species in the Great Lakes region and highlight a need for additional work on Canadian B. paniculata subsp. paniculata taxonomy prior to a reevaluation of its conservation value. Key words: disjunct populations, conservation, phylogeography, Great Lakes, Bartonia paniculata. La comprehension de la distribution spatiale de la diversite genetique ainsi que de son histoire evolutive constitue une partie essentielle pour le developpement de plans d'amenagement efficace de la biodiversite. Ceci peut possiblement s'averer juste lorsque l'on considere la valeur des populations peripheriques ou disjointes. Bien que les decisions de conservation soient souvent effectuees en reference aux frontieres geopolitiques, plusieurs responsables des politiques considerent egalement les distributions globales, et consequemment l'etat global d'une espece peut moduler leur etat regional. On peut trouver plusieurs populations disjointes dans la region des Grands Lacs en Amerique du Nord, incluant celles du Bartonia paniculata subsp. paniculata, une espece ayant ete designee comme menacees au Canada, mais globalement securisee. Les auteurs ont compare les sequences chloroplastiques entre des populations disjointes (Canada) et centrales (EU) du B. paniculata subsp. paniculata separees de 600 km, ce qui constitue la distance minimale entre les populations disjointes et centrales chez cette sous-espece. Bien que les lignees dans les populations disjointes partagent un ancetre commun relativement recent, ils ont constate que la divergence genetique entre les plantes d'Ontario et du New Jersey s'avere substantiellement plus grande qu'attendu dans le cadre d'une comparaison consubspecifique. Une analyse basee sur la coalescence fait remonter l'ancetre commun le plus recent des populations canadiennes et americaines a environ 534 000 ans avant le present, l'estimation de moindre confiance etant 226 000 avant le present. Ceci antidate substantiellement le maximum de la derniere glaciation et suggere que les populations disjointes et centrales auraient suivi des trajectoires evolutives independantes a travers divers cycles de glaciation. Ces constatations jettent un important eclairage sur les divers processus ayant conduit a plusieurs especes distinctes dans la region des Grands Lacs et soulignent le besoin de poursuivre un travail additionnel sur la taxonomie du B. paniculata subsp. paniculata canadien avant de reevaluer sa valeur de conservation. [Traduit par la Redaction] Mots-cles: populations disjointes, conservation, phylogeographie, Grands Lacs, Bartonia paniculata., Introduction Plant populations that occur toward the limits of species' distributions often make important contributions to local biodiversity (Nantel and Gagnon 1999); however, many such populations have been identified as [...]

Abstract Background The impact of global climate change on plant distribution, speciation and extinction is of current concern. Examining species climatic preferences via bioclimatic niche modelling is a key tool to study this impact. There is an established link between bioclimatic niche models and phylogenetic diversification. A next step is to examine future distribution predictions from a phylogenetic perspective. We present such a study using Cyclamen (Myrsinaceae), a group which demonstrates morphological and phenological adaptations to its seasonal Mediterranean-type climate. How will the predicted climate change affect future distribution of this popular genus of garden plants? Results We demonstrate phylogenetic structure for some climatic characteristics, and show that most Cyclamen have distinct climatic niches, with the exception of several wide-ranging, geographically expansive, species. We reconstruct climate preferences for hypothetical ancestral Cyclamen. The ancestral Cyclamen lineage has a preference for the seasonal Mediterranean climate characteristic of dry summers and wet winters. Future bioclimatic niches, based on BIOCLIM and Maxent models, are examined with reference to a future climate scenario for the 2050s. Over the next 50 years we predict a northward shift in the area of climatic suitability, with many areas of current distribution becoming climatically unsuitable. The area of climatic suitability for every Cyclamen species is predicted to decrease. For many species, there may be no areas with a suitable climate regardless of dispersal ability, these species are considered to be at high risk of extinction. This risk is examined from a phylogenetic perspective. Conclusion Examining bioclimatic niches from a phylogenetic perspective permits novel interpretations of these models. In particular, reconstruction of ancestral niches can provide testable hypothesis about the historical development of lineages. In the future we can expect a northwards shift in climatic suitability for the genus Cyclamen. If this proves to be the case then dispersal is the best chance of survival, which seems highly unlikely for ant-dispersed Cyclamen. Human-assisted establishment of Cyclamen species well outside their native ranges offers hope and could provide the only means of dispersal to potentially suitable future environments. Even without human intervention the phylogenetic perspective demonstrates that major lineages could survive climate change even if many species are lost.