Correction to: Scientific Reports https://doi.org/10.1038/s41598-019-52250-1, published online 01 Novenber 2019 The original version of this Article contained errors in the Abstract. "Sponge biomass surfaces created from research survey data using both random forest modeling and a gridded surface revealed 231,140 t of sponges in the area. About 65% of that biomass was protected by current fisheries closures." now reads: "Sponge biomass surface created from research survey data using random forest modeling revealed 231,136 t of sponges in the area. About 42% of that biomass was protected by current fisheries closures." This error has now been corrected in the PDF and HTML versions of the Article.
ABSTRACT Deep-sea sponge grounds are vulnerable marine ecosystems, which through their benthic-pelagic coupling of nutrients, are of functional relevance to the deep-sea realm. The impact of fishing bycatch is here evaluated for the first time at a bathyal, sponge-dominated ecosystem in the high seas managed by the Northwest Atlantic Fisheries Organization. Sponge biomass surfaces created from research survey data using both random forest modeling and a gridded surface revealed 231,140 t of sponges in the area. About 65% of that biomass was protected by current fisheries closures. However, projections of trawling tracks estimated that the sponge biomass within them would be wiped out in just 1 year by the current level of fishing activity if directed on the sponges. Because these sponges filter 56,143 ± 15,047 million litres of seawater daily, consume 63.11 ± 11.83 t of organic carbon through respiration, and affect the turnover of several nitrogen nutrients, their removal would likely affect the delicate ecological equilibrium of the deep-sea benthic ecosystem. We estimated that, on Flemish Cap, the economic value associated with seawater filtration by the sponges is nearly double the market value of the fish catch. Hence, fishery closures are essential to reach sponge conservation goals as economic drivers cannot be relied upon. ; DATA AVAILABILITY: The authors confirm that all data underlying the findings are fully available without restriction. Data from Canadian research vessel surveys are deposited in the Ocean Biogeographic Information System (OBIS) at http://obiscanada.marinebiodiversity.ca/or http://www.iobis.org/. Spanish/EU data are available at Figshare with the https://doi.org/10.6084/m9.figshare.1165479. ACKNOWLEDGEMENTS: This research has been performed within the scope of the SponGES project, which received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 679849. This document reflects only the authors' views and the Executive Agency for ...
ABSTRACT. The ecological diversity of benthic invertebrates from bottom trawl surveys was mapped for the Flemish Cap, a plateau of ~200 km radius in the northwest Atlantic. Species density (SpD), the exponential Shannon diversity index (eH′) and Heip's index of evenness (E~') were measured at different spatial scales. Continuous surfaces of each were created to 2000 m depth using predictive distribution models based on random forest (RF) algorithms. When fishing effort was included as an independent variable in the RF models, it was the most important predictor of sample SpD but unimportant in predicting eH′ and only a minor predictor of E~'. In the absence of a historical baseline, we used a novel approach to evaluate spatial impacts of fishing on diversity by simulating and comparing spatial SpD prediction surfaces using response data associated with different levels of fishing effort. Although it is not possible to fully evaluate the precise nature of the impact of fishing on the ecological diversity, our models have identified Sackville Spur, Flemish Pass and south of Flemish Cap as the areas of greatest impact. Combining minimum bottom salinity, annual primary production range, fishing effort and biomass of sponges and small gorgonian corals, resulted in the best performing generalized additive model, explaining 73% of the total variance in SpD. Although current closures to protect vulnerable marine ecosystems from the adverse impacts of bottom fishing activities protect an important part of the ecological diversity associated with the deeper communities, unique and representative habitats on top of the Cap remain unprotected. HIGHLIGHTS • The structure-forming sponges and small gorgonian corals enhance biodiversity. • Chronic impact from fishing activities have negatively impacted benthic diversity. • Over 60% of the estimated number of benthic species of the Flemish Cap is under protection. • Biodiversity from shallow waters remains unprotected. ; ACKNOWLEDGEMENTS. This research was funded by Fisheries ...
ABSTRACT. In the last two decades the use of species distribution modeling (SDM) for the study and management of marine species has increased dramatically. The availability of predictor variables on a global scale and the ease of use of SDM techniques have resulted in a proliferation of research on the topic of species distribution in the deep sea. Translation of research projects into management tools that can be used to make decisions in the face of changing climate and increasing exploitation of deep-sea resources has been less rapid but necessary. The goal of this workshop was to discuss methods and variables for modeling species distributions in deep-sea habitats and produce standards that can be used to judge SDMs that may be useful to meet management and conservation goals. During the workshop, approaches to modeling and environmental data were discussed and guidelines developed including the desire that 1) environmental variables should be chosen for ecological significance a priori; 2) the scale and accuracy of environmental data should be considered in choosing a modeling method; 3) when possible proxy variables such as depth should be avoided if causal variables are available; 4) models with statistically robust and rigorous outputs are preferred, but not always possible; and 5) model validation is important. Although general guidelines for SDMs were developed, in most cases management issues and objectives should be considered when designing a modeling project. In particular, the trade-off between model complexity and researcher's ability to communicate input data, modeling method, results and uncertainty is an important consideration for the target audience. RÉSUMÉ. Au cours des deux dernières décennies, le recours à la modélisation de la répartition des espèces pour étudier et gérer les espèces marines a considérablement augmenté. La disponibilité des variables prédictives à l'échelle mondiale et la convivialité de ces techniques de modélisation ont entraîné la multiplication des recherches sur la ...
