30 research outputs found
Discerning the Management-Relevant Ecology and Distribution of Sea Pens (Cnidaria: Pennatulacea) in Norway and Beyond
Sea pens are considered to be of conservation relevance according to multiple international legislations and agreements. Consequently, any information about their ecology and distribution should be of use to management decision makers. This study aims to provide such information about six taxa of sea pen in Norwegian waters [Funiculina quadrangularis (Pallas, 1766), Halipteris spp., Kophobelemnon stelliferum (MĂŒller, 1776), Pennatulidae spp., Umbellula spp., and Virgulariidae spp.]. Data exploration techniques and ensembled species distribution modelling (SDM) are applied to video observations obtained by the MAREANO project between 2006 and 2020. Norway-based ecological profiles and predicted distributions are provided and discussed. External validations and uncertainty metrics highlight model weaknesses (overfitting, limited training/external observations) and consistencies relevant to marine management. Comparison to international literature further identifies globally relevant findings: (a) disparities in the environmental profile of F. quadrangularis suggest differing ârealised nichesâ in different locations, potentially highlighting this taxon as particularly vulnerable to impact, (b) none of the six sea pen taxa were found to consistently co-occur, instead partially overlapping environmental profiles suggests that grouping taxa as âsea pens and burrowing megafaunaâ should be done with caution post-analyses only, (c) higher taxonomic level groupings, while sometimes necessary due to identification issues, result in poorer quality predictive models and may mask the occurrence of rarer species. Community-based groupings are therefore preferable due to confirmed shared ecological niches while greater value should be placed on accurate species ID to support management efforts.publishedVersio
Modeling the Distribution of Habitat-Forming, Deep-Sea Sponges in the Barents Sea: The Value of Data
The use of species occurrence as a proxy for habitat type is widespread, probably because it allows the use of species distribution modeling (SDM) to cost-effectively map the distribution of e.g., vulnerable marine ecosystems. We have modeled the distribution of epibenthic megafaunal taxa typical of soft-bottom, Deep-Sea Sponge Aggregations (DSSAs), i.e., âindicators,â to discover where in the Barents Sea region this habitat is likely to occur. The following taxa were collectively modeled: Hexadella cf. dedritifera, Geodia spp., Steletta sp., Stryphnus sp. The data were extracted from MarVid, the video database for the Marine AREAl database for NOrwegian waters (MAREANO). We ask whether modeling density data may be more beneficial than presence/absence data, and whether using this list of indicator species is enough to locate the target habitat. We use conditional inference forests to make predictions of probability of presence of any of the target sponges, and total density of all target sponges, for an area covering a large portion of the Norwegian Barents Sea and well beyond the dataâs spatial range. The density models explain 0.88), depending on the variables/samples used to train the model. The predicted surfaces were then classified on the basis of a probability threshold (0.75) and a density threshold (13 n/100 m2) to obtain polygons of âcore areaâ and âhotspotsâ respectively (zones). The DSSA core area comprises two main regions: the Egga shelf break/TromsĂžflaket area, and the shelf break southwest of RĂžst bank in the TrĂŠna trench. Four hotspots are detected within this core area. Zones are evaluated in the light of whole-community data which have been summarized as taxon richness and density of all megafauna. Total megafaunal density was significantly higher inside the hotspots relative to the background. Richness was not different between zones. Hotspots appeared different to one another in their richness and species composition although no tests were possible. We make the case that the effectiveness of the indicator species approach for conservation planning rests on the availability of density data on the target species, and data on co-occurring species.publishedVersio
Seabed Mapping and Marine Spatial Planning: A Case Study from a Swedish Marine Protected Area
Physical chemistr
Chapter Seabed Mapping and Marine Spatial Planning: A Case Study from a Swedish Marine Protected Area
Physical chemistr
Using Spatial Validity and Uncertainty Metrics to Determine the Relative Suitability of Alternative Suites of Oceanographic Data for Seabed Biotope Prediction. A Case Study from the Barents Sea, Norway
The use of habitat distribution models (HDMs) has become common in benthic habitat mapping for combining limited seabed observations with full-coverage environmental data to produce classified maps showing predicted habitat distribution for an entire study area. However, relatively few HDMs include oceanographic predictors, or present spatial validity or uncertainty analyses to support the classified predictions. Without reference studies it can be challenging to assess which type of oceanographic model data should be used, or developed, for this purpose. In this study, we compare biotope maps built using predictor variable suites from three different oceanographic models with differing levels of detail on near-bottom conditions. These results are compared with a baseline model without oceanographic predictors. We use associated spatial validity and uncertainty analyses to assess which oceanographic data may be best suited to biotope mapping. Our results show how spatial validity and uncertainty metrics capture differences between HDM outputs which are otherwise not apparent from standard non-spatial accuracy assessments or the classified maps themselves. We conclude that biotope HDMs incorporating high-resolution, preferably bottom-optimised, oceanography data can best minimise spatial uncertainty and maximise spatial validity. Furthermore, our results suggest that incorporating coarser oceanographic data may lead to more uncertainty than omitting such data.publishedVersio
Analysis of spatial conflicts of large scale salmonid aquaculture with coastal fisheries and other interests in a Norwegian fjord environment, using the novel GIS-tool SEAGRID and stakeholder surveys
The expansion of the Norwegian aquaculture industry has generated a need for balancing aquaculture with other societal interests in the coastal zone. The interactions, conflicts and synergies of different uses of a Norwegian coastal region heavily influenced by large-scale salmonid aquaculture was analyzed and mapped by means of systematic stakeholder participatory approach and a GIS-based spatial interaction analysis tool, SEAGRID. Our study focused on spatial conflicts/synergies, whereas non-spatial interactions were taken into account in order to elucidate the spatial effects. The questionnaire analysis showed that there was a large agreement across the respondents that aquaculture and fisheries compete for access to sea areas, which is also in agreement with the SEAGRID analysis. All but one of the interviewees thought that conservation issues will become more important in the future. We found that societal interests and infrastructure obstruct or displace private enterprises and economic interests, whereas environmental protection measures do so to a lesser extent; an exception are coral reefs which seem to be well protected against both fishing operations as well as new aquaculture facilities. Nature protection was not found to affect fisheries nor aquaculture to a large extent, with the exception of the single salmon fjord, which is protected from salmonid aquaculture, but otherwise open to other activities, such as fisheries, tourist fisheries and tourism in general. The restricted military areas had a limited extent, and were not viewed as a cause of conflicts. Stakeholder consultations, like our participatory GIS approach, combined with GIS-based tools for analysis of spatial conflicts/synergies may be useful in identifying areas where aquaculture production can increase with little increase in degree of conflict with fisheries, although some interactions are not strictly spatial. Our results indicated a certain degree of mistrust of management authorities since neither fishermen nor aquaculturists perceived that their own sector was given priority by management authorities, but thought the other sector was prioritized.Analysis of spatial conflicts of large scale salmonid aquaculture with coastal fisheries and other interests in a Norwegian fjord environment, using the novel GIS-tool SEAGRID and stakeholder surveyspublishedVersio
Marinbiologisk mangfold i Andfjorden marine verneomrÄde
Andfjorden marine verneomrÄde er et stort omrÄde som strekker seg fra fjord til hav. OmrÄdet har en variert topografi som gir levested for en stor variasjon av marine arter. Her finnes rekefelt og gyteomrÄder for torsk, kveite, uer og rognkjeks. En rekke naturtyper er kartlagt i omrÄdet slik som skjellsand, tareskog og ruglbunn. SÄrbare naturtyper som korallrev, bambuskorallskog, hardbunnskorallskog, svampskog og sjÞfjÊrbunn er observert gjennom Mareano undersÞkelser og av fiskere i Andfjorden. For fÞrste gang er biotop-modellering brukt som redskap for Ä predikere forekomsten av hardbunnskoraller, blÞtbunnskoraller og svampskog i et marint verneomrÄde pÄ norskekysten.publishedVersio
Tests of set of management tools: performance evaluation and validation of the management tools. Deliverable 4.4 of Project MESMA, Monitoring and Evaluation of Spatially Managed Areas, EU FP7
Cruise report Hywind Tampen 13 to 28 March 2023 - Cruise no. 2023001004 G.O. Sars
Source at https://www.hi.no/hi.There is very little knowledge related to how floating windfarms effect the marine environment as this is such a new âproductâ. Thus, the data that we gathered on this cruise will be novel in that sense. The aim of the cruise was to look at possible effects of the windfarm on the marine environment. Based on limited cruise time and tough weather conditions around Hywind Tampen we had to be selective related to topics for this first cruise, and we choose to focus on the following: 1) Measuring noise from the turbine. This we did by deploying a hydrophone mooring within the windfarm. 2) Measuring current to track possible changes in current and wake effect. We did this by deploying ADCPâs within and around the windfarm, and by conducting CTD transects around and within the windfarm. 3) Look at possible effects on pelagic fish distribution, by conducting acoustics transects with RV G.O. Sars's multi-frequency acoustics, within and around the windfarm. As the RV G.O. Sars is not allowed closer then 500m to the turbines, we conducted acoustic transects with an acoustic kayak-drone within the 500 m range to the wind turbines. The kayak being allowed as close as 15-20m to the turbines. To able ground truthing of acoustic findings we trawled with an open trawl equipped with a camera (DeepVision) and we took eDNA samples along the transects. 4) Effect of bottom structure on the benthic fauna. This was studied by ROV transects filming fauna around 3 suction anchors and the adjacent chains connecting the turbines to the anchor. ROV control transects were conducted from the very same suction anchors, but on a line moving away from the windfarm. This cruise was conducted in collaboration with the NFR-funded WindSys project
Cruise report Hywind Tampen 13 to 28 March 2023 - Cruise no. 2023001004 G.O. Sars
There is very little knowledge related to how floating windfarms effect the marine environment as this is such a new âproductâ. Thus, the data that we gathered on this cruise will be novel in that sense. The aim of the cruise was to look at possible effects of the windfarm on the marine environment. Based on limited cruise time and tough weather conditions around Hywind Tampen we had to be selective related to topics for this first cruise, and we choose to focus on the following: 1) Measuring noise from the turbine. This we did by deploying a hydrophone mooring within the windfarm. 2) Measuring current to track possible changes in current and wake effect. We did this by deploying ADCPâs within and around the windfarm, and by conducting CTD transects around and within the windfarm. 3) Look at possible effects on pelagic fish distribution, by conducting acoustics transects with RV G.O. Sars's multi-frequency acoustics, within and around the windfarm. As the RV G.O. Sars is not allowed closer then 500m to the turbines, we conducted acoustic transects with an acoustic kayak-drone within the 500 m range to the wind turbines. The kayak being allowed as close as 15-20m to the turbines. To able ground truthing of acoustic findings we trawled with an open trawl equipped with a camera (DeepVision) and we took eDNA samples along the transects. 4) Effect of bottom structure on the benthic fauna. This was studied by ROV transects filming fauna around 3 suction anchors and the adjacent chains connecting the turbines to the anchor. ROV control transects were conducted from the very same suction anchors, but on a line moving away from the windfarm. This cruise was conducted in collaboration with the NFR-funded WindSys project.Cruise report Hywind Tampen 13 to 28 March 2023 - Cruise no. 2023001004 G.O. SarspublishedVersio