scholarly journals Distribution of macroalgae in the area of Calvi (Corsica)

2021 ◽  
Vol 9 ◽  
Author(s):  
Lea Katz ◽  
Damien Sirjacobs ◽  
Sylvie Gobert ◽  
Pierre Lejeune ◽  
Bruno Danis
Keyword(s):  
Habitat Type ◽  
Marine Biodiversity ◽  
Benthic Habitat ◽  
Remotely Operated Vehicle ◽  
Invasive Algae ◽  
The Status ◽  
Caulerpa Prolifera ◽  
Benthic Ecosystems ◽  
Conservation Plans ◽  
Lower Limits

Macroalgae play a structuring role in benthic ecosystems, which makes it very important to monitor their cover rates and study their community structures and changes in time. Such studies are usually led by autonomous divers and often do not generate sufficient data to provide enough material for strategically-sound conservation plans. This paper describes the dataset generated in the framework of the evaluation of the potential of a complementary data acquisition method: annotating videos transects obtained using an underwater Remotely Operated Vehicle (ROV). The focus was on Cystoseira brachycarpa, together with the abundance of several other macroalgae species, which could be identified using the ROV images after validation through specimen identification. Furthermore, in order to allow future uses, such as monitoring the status of colonisation of the invasive algae Caulerpa cylindracea, the ROV was sent to some deeper transects on sedimentary habitats (40 m) below the Posidonia meadows lower limits. The project, while providing some interesting insights on using a ROV as a tool to study marine biodiversity, generated a dataset for the distribution of 19 macroalgae on both standardised and new transects in the Bay of Calvi (Katz et al. 2021). The observed species of macroalgae included: Acetabularia acetabulum, Amphiroa rigida, Caulerpa prolifera, Caulerpa cylindracea, Codium bursa, Colpomenia sinuosa, Corallinales (order), Cystoseira brachycarpa, Cystoseira crinita, Cystoseira spinosa, Cystoseira zosteroides, Dictyota (genus), Flabellia petiolata, Halopteris (genus), Halopteris scoparia, Jania (genus), Osmundaria volubilis, Padina pavonica and Peyssonnelia squamaria. The videos also showed that the invasive algae Caulerpa cylindracea has spread between 2016 and 2019 and that more focused studies should be held in the Bay to assess the actual reach and possible impacts of this invasion. Finally, our ROV video transects have also underlined the significant presence of particular benthic macroalgae communities over habitat zones described as "soft-bottom" on benthic habitat maps. Although the biomass per unit area of these communities is probably lower than for most coastal rocky bottoms, this widely-spread habitat type holds a contribution to primary production to be considered in coastal ecosystem models.

scholarly journals The Vulnerable Indian Skimmer Rynchops albicollis Swainson, 1838 (Aves: Charadriiformes: Laridae) breeding in Odisha, eastern India

2017 ◽  
Vol 9 (11) ◽  
pp. 10961 ◽  
Author(s):  
Subrat Debata ◽  
Tuhinansu Kar ◽  
Kedar Kumar Swain ◽  
Himanshu Shekhar Palei
Keyword(s):  
West Bengal ◽  
Uttar Pradesh ◽  
Breeding Site ◽  
Madhya Pradesh ◽  
Eastern India ◽  
Mahanadi River ◽  
The North ◽  
The Status ◽  
Global Status ◽  
Conservation Plans

The Indian Skimmer is a globally threatened bird native to Bangladesh, India, Myanmar, Nepal, Pakistan, and Vietnam.  In India, it is more confined to the north, from Punjab through Uttar Pradesh, Madhya Pradesh to West Bengal, extending up to Odisha.  Earlier, the bird was known to breed only in Uttar Pradesh and Madhya Pradesh, we confirm here the breeding of the Indian Skimmer along the river Mahanadi near Mundali, Odisha, eastern India.  So, further monitoring at the breeding site and survey along the entire Mahanadi River are essential to understand the status of the Indian skimmer in Odisha.  The information will also aid in reassessing its global status and formulating conservation plans.

scholarly journals FEATURES OF THE FORMATION AND VALUATION OF INSURANCE RESERVES

2021 ◽  
Author(s):  
Maxim Kompaniets ◽  
Inna Kysilyova
Keyword(s):  
Insurance Companies ◽  
Insurance Company ◽  
Strategic Decisions ◽  
Method Of Calculation ◽  
Loss Reserve ◽  
Management Efficiency ◽  
The Status ◽  
Conducting Research ◽  
Economic Nature ◽  
Lower Limits

The purpose of the paper is research of practice of making insurance reserves of the insurance companies in Ukraine and summarizes the ways of improvement of methods for their calculation with the purpose of increasing management efficiency of an organization. The article addresses the characteristics and economic nature of certain types of technical reserves of insurance organizations in particular the unencumbered premiums reserve, the loss reserve and the catastrophe reserve, and the characteristics of their formation. Major methods for calculating the reserve of unencumbered premiums reviewed and recommended adjustment to method 1/36 , and use of the reserve calculation method of unencumbered premiums, which takes into account inflation ratio. The method of calculation and formation of the loss reserve is considered as well as the characteristics of the reserve for past but undeclared losses and reserves for asserted but unresolved losses. The system of indicators of sufficiency of insurance reserves of insurance organizations was analyzed; the calculation formulae and recommended values are given. Insurance reserves sufficiency ratios refers to the status of insurance reserves and determine the adequacy of insurance reserves to the risks taken into insurance. Sufficiency ratio (based on premiums) and sufficiency ratio (based on payments) determine, respectively, the upper and lower limits of insurance reserves. For conducting research and substantiation of relevant conclusions, the indicators of dynamics and structure of insurance reserves of insurance company JSC IC “INGO” are analyzed. Sufficiency ratios for insurance reserves of JSC IC “INGO” are also calculated and Evaluation of the company’s insurance reserves has been performed. The results of the study can be applied by the heads of the financial divisions of insurance companies for the development of tactical and strategic decisions that allows to yield optimal condition of insurance reserves and their reliable valuation of insurance company and to perform the quick analysis of the state of insurance reserves of insurance company.

Benthic Habitats and the Effects of Fishing

2005 ◽  
Keyword(s):  
Habitat Type ◽  
High Energy ◽  
Benthic Habitat ◽  
Commercial Fishing ◽  
Placopecten Magellanicus ◽  
Benthic Species ◽  
Habitat Types ◽  
Closed Area ◽  
Sea Scallops ◽  
Moderate Complexity

<strong><em>Abstract. </em></strong>In late 1994, substantial portions of Georges Bank were closed to commercial fishing to assist with stock rebuilding. These areas were Closed Area I (CAI), located on the western portion of the bank, and Closed Area II (CAII), on the eastern portion. After about 5 years of closure, the southern portion of CAII and the central portion of CAI, having exhibited substantial increases in biomass and density of sea scallops <em>Placopecten magellanicus</em>, were reopened to scallop fishing. Before the industry was allowed entry, we conducted surveys to monitor the recovery of benthic habitat and fauna inside both areas. Sampling sites were selected in a paired station design for an inside–outside comparison representative of major habitat types in each closed area; other stations were chosen to survey the remainder of the closed areas. At each station, we examined a suite of biotic and abiotic variables ranging from substrate type to benthos to nekton. Our results suggest few differences between the inside–outside paired stations in both closed areas for nekton and benthic species composition and species richness. Fish abundance and biomass were similar inside and outside the closed areas. However, individuals of species such as skates (<em>Raja </em>spp.), haddock <em>Melanogrammus aeglefinus</em>, and flounders (Pleuronectiformes) were generally larger inside than outside the closed areas. Additionally, habitat type was important in determining the distribution, abundance, biomass, size, and feeding ecology for some of the more benthic-oriented species studied. In CAI, the differences we observed in the suite of biotic metrics are likely a result of the high diversity of habitat types, with many of the habitat types composed of higher-relief material (e.g., cobble, gravel, etc.) in the region. The seabed in the southern portion of CAII is a relatively high-energy sand habitat of low to moderate complexity and has a relatively low vulnerability to trawling and dredging, which may explain why there were less pronounced differences in abundance or biomass across habitat types in that closed area as compared to CAI. Other parts of closed areas on the northeastern shelf may exhibit more obvious changes in the same biological metrics due to the presence of more complex habitats and increased vulnerability to bottom tending fishing gear. Those differences we observed for CAI and CAII may have implications for the population dynamics of commercially valuable benthic species, yet that question remains a major challenge.

scholarly journals Benthic Habitat Morphodynamics-Using Remote Sensing to Quantify Storm-Induced Changes in Nearshore Bathymetry and Surface Sediment Texture at Assateague National Seashore

2019 ◽  
Vol 7 (10) ◽  
pp. 371 ◽  
Author(s):  
Arthur Trembanis ◽  
Alimjan Abla ◽  
Ken Haulsee ◽  
Carter DuVal
Keyword(s):  
Multiple Scales ◽  
Habitat Type ◽  
Hurricane Sandy ◽  
Temporal Association ◽  
Benthic Habitat ◽  
Offshore Area ◽  
Side Scan Sonar ◽  
Marine Habitats ◽  
Induced Changes ◽  
National Seashore

This study utilizes repeated geoacoustic mapping to quantify the morphodynamic response of the nearshore to storm-induced changes. The aim of this study was to quantitatively map the nearshore zone of Assateague Island National Seashore (ASIS) to determine what changes in bottom geomorphology and benthic habitats are attributable to storm events including hurricane Sandy and the passage of hurricane Joaquin. Specifically, (1) the entire domain of the National Parks Service offshore area was mapped with side-scan sonar and multibeam bathymetry at a resolution comparable to that of the existing pre-storm survey, (2) a subset of the benthic stations were resampled that represented all sediment strata previously identified, and (3) newly obtained data were compared to that from the pre-storm survey to determined changes that could be attributed to specific storms such as Sandy and Joaquin. Capturing event specific dynamics requires rapid response surveys in close temporal association of the before and after period. The time-lapse between the pre-storm surveys for Sandy and our study meant that only a time and storm integrated signature for that storm could be obtained whereas with hurricane Joaquin we could identify impacts to the habitat type and geomorphology more directly related to that particular storm. This storm impacts study provides for the National Park Service direct documentation of storm-related changes in sediments and marine habitats on multiple scales: From large scale, side-scan sonar maps and interpretation of acoustic bottom types, to characterize as fully as possible habitats from 1 to 10 m up to many kilometer scales, as well as from point benthic samples within each sediment stratum and these results can help guide management of the island resources.

scholarly journals Cloud rats in the Philippines — preliminary report on distribution and status

Oryx ◽  
1993 ◽  
Vol 27 (1) ◽  
pp. 41-48 ◽  
Author(s):  
W. L. R. Oliver ◽  
C. R. Cox ◽  
P. C. Gonzales ◽  
L. R. Heaney
Keyword(s):  
New Species ◽  
Preliminary Report ◽  
Field Survey ◽  
The Philippines ◽  
Type Locality ◽  
The Status ◽  
Conservation Plans ◽  
Do So

This paper describes a preliminary field survey of bushy-tailed cloud rats Crateromys spp. and slender-tailed cloud rats Phloeomys in the Philippines in April and May 1990. Brief visits were made to all islands/locations known to support these animals and also to neighbouring areas considered likely to do so. Comparing the results with information from previous surveys suggests that both genera, particularly Crateromys, are more widely distributed than formerly believed, but that some forms are threatened. Three of the four known species of Crateromys are known only from their holotype specimens, one of which awaits description. Another is extinct in its type locality on Ilin Island but may survive on neighbouring Mindoro. These preliminary findings indicate that thorough surveys are required to establish the status of certain species, to investigate the possibility that new species remain undiscovered and to develop conservation plans to reduce the likelihood of further extinctions occurring.

scholarly journals Towards a global dataset of seagrass occurrences: current progress, knowledge gaps and challenges

2015 ◽  
Author(s):  
Lauren Weatherdon ◽  
Corinne S Martin ◽  
Chris Mcowen ◽  
Hannah Thomas
Keyword(s):  
Sustainable Use ◽  
Marine Conservation ◽  
United Nations Environment Programme ◽  
Marine Biodiversity ◽  
Knowledge Gaps ◽  
Policy Makers ◽  
Monitoring Centre ◽  
Global Science ◽  
Marine Habitats ◽  
The Status

For a number of years, the United Nations Environment Programme World Conservation Monitoring Centre (UNEP-WCMC) has collaborated with Dr. Frederic Short (SeagrassNet, University of New Hampshire) and other seagrass experts worldwide to compile a global georeferenced dataset of seagrass occurrences. More than 184,000 point and polygon records have been collated to date. The GIS dataset and associated metadata can be downloaded from UNEP-WCMC’s Ocean Data Viewer, thereby providing ready-for-use information on the location of this critical habitat to policy-makers, conservationists, and scientists. This knowledge is necessary to inform better decisions regarding marine conservation (e.g., marine spatial planning) and to ensure the sustainable use of our ocean’s resources (e.g., ecosystem service valuation). This and other similar datasets on the distribution of key marine habitats—e.g., saltmarshes, mangroves, and corals (also curated and distributed by UNEP-WCMC)—have been used in numerous global and regional studies that examine the status of sensitive marine biodiversity and related impacts. Occurrence datasets such as these are also used to inform predictive models aimed at filling spatial gaps in knowledge. Moreover, such a global dataset can support analyses that explore the contribution of seagrass and other ‘blue carbon’ ecosystems (e.g. saltmarsh, mangrove) to carbon sequestration, thereby aiding climate change mitigation. As part of an interactive session, we will: 1. Present current progress towards collating a global dataset of seagrass occurrences, highlighting the achievements of such collaborative endeavours and the relevance of this dataset to global science, conservation, and policy initiatives; and 2. Facilitate a discussion with Mediterranean seagrass experts to develop recommendations for addressing the knowledge gaps and challenges (e.g. licensing issues) that have been identified. In particular, this session will focus on improving our collective knowledge of the spatial distribution of seagrass ecosystems in data-poor regions of the Mediterranean by drawing from local and regional expertise. Given the importance of these ecosystems to sustaining marine biodiversity, regulating carbon, and supporting global fisheries, such contributions towards developing a comprehensive and accurate dataset can help to ensure that scientists, conservationists, policy-makers and other decision-makers have the appropriate information to make better-informed analyses and decisions.

scholarly journals A new threat to local marine biodiversity: filamentous mats proliferating at mesophotic depths off Rapa Nui

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12052
Author(s):  
Javier Sellanes ◽  
Matthias Gorny ◽  
Germán Zapata-Hernández ◽  
Gonzalo Alvarez ◽  
Praxedes Muñoz ◽  
...  
Keyword(s):  
Green Alga ◽  
Brown Alga ◽  
Easter Island ◽  
Marine Biodiversity ◽  
Filamentous Cyanobacteria ◽  
Rapa Nui ◽  
Remotely Operated Vehicle ◽  
Morphologic Analysis ◽  
Western Side

Mesophotic and deeper habitats (∼40 to 350 m in depth) around Rapa Nui (Easter Island) were investigated using a remotely operated vehicle. We observed extensive fields of filamentous cyanobacteria-like mats covering sandy substrates and mostly dead mesophotic Leptoseris spp. reefs. These mats covered up to 100% of the seafloor off Hanga Roa, the main village on the island, located on its western side. The highest mortality of corals was observed at depths between 70 and 95 m in this area. Healthy Leptoseris reefs were documented off the northern and southeastern sides of the island, which are also the least populated. A preliminary morphologic analysis of samples of the mats indicated that the assemblage is composed of at least four filamentous taxa, including two cyanobacteria (cf. Lyngbya sp. and Pseudoanabaena sp.), a brown alga (Ectocarpus sp.), and a green alga (Cladophora sp.). An ongoing eutrophication process is suggested as a potential driver of the proliferation of these filamentous mats off Hanga Roa village.

scholarly journals Marine Fishes Expert Network: findings and recommendations from the Circumpolar Biodiversity Monitoring Program’s State of the Arctic Marine Biodiversity Report

2018 ◽  
Author(s):  
Kevin J Hedges ◽  
Shannon MacPhee ◽  
Hreiðar Þór Valtýsson ◽  
Edda Johannesen ◽  
Catherine W Mecklenburg
Keyword(s):  
Marine Fish ◽  
Marine Mammals ◽  
Prey Availability ◽  
Marine Fishes ◽  
The Arctic ◽  
Marine Biodiversity ◽  
Transfer Energy ◽  
Status And Trends ◽  
The Status ◽  
Expert Network

Pelagic and benthic fish species are important in Arctic marine ecosystems because they transfer energy to predators such as seabirds, marine mammals, as well as people. The CBMP Marine Fishes Expert Network aggregated and reviewed data on the population status and trends of three marine fish Focal Ecosystem Components (FECs) across eight Arctic Marine Areas. Fishes are affected by environmental conditions such as temperature, sea ice availability and salinity, and are constrained by prey availability and predator pressure, which can be influenced by climate change. The three marine fish FECs discussed here are indicative of different changes that are occurring in the Arctic and demonstrate the varied responses observed among species. The presentation will summarize current level of monitoring across the Arctic, the status and trends of FECs, drivers of observed trends, and knowledge and monitoring gaps.

The impacts of hydraulic clamming in shallow water and the importance of incorporating anthropogenic disturbances into habitat assessments

2020 ◽  
Vol 33 ◽  
pp. 13
Author(s):  
Bryan Legare ◽  
Agnes Mittermayr ◽  
Mark Borrelli
Keyword(s):  
Habitat Type ◽  
Anthropogenic Disturbances ◽  
Benthic Invertebrate ◽  
Grain Size Analysis ◽  
Size Analysis ◽  
Benthic Habitat ◽  
Significance Level ◽  
Type D ◽  
Sample Statistic ◽  
Post Impact

Hydraulic dredging for shellfish is known to create some of the highest levels of disturbance, affecting the benthic microfaunal community and the physical characteristics of the substrate. Properly conducted benthic habitat assessments are complex and time consuming, resulting in assessments not being conducted increasing the uncertainty in post impact studies. Hydraulic dredging for Atlantic surfclams (Spisula soldidissima) took place at Herring Cove, Massachusetts in the winter of 2014–2015 resulting in areas of high impact disturbance of the seafloor. Surveys conducted in the summer of 2015 included hydroacoustics, benthic invertebrate sampling, video, and grain size analysis for the creation of a habitat map of Herring Cove. The four habitats (A–D) identified were a mix of sand, shell, cobble, algae, and eelgrass. Habitat type “D” is a mix of sand, algae and cobble material and occurred at 12 of 18 stations. These 12 stations were distributed across areas of “high” (n = 4), “low” (n = 2), and “no” (n = 6) hydraulic dredge disturbance. Once habitat was accounted for, benthic invertebrate community structure varied significantly (Analysis of similarity; significance level of sample statistic: 0.3%) between areas of “high”, “low” to “no” disturbance. Areas of “low” to “no” dredge track coverage contained high abundances of bivalves, echinoderms, and isopods, whereas highly disturbed areas had highest abundances of polychaetes and oligochaetes. Future mapping efforts, especially surveys with biological components, need to include and quantify the level, type and spatial distribution of anthropogenic alterations. More attention should be given to “reference maps” instead of “baseline maps”. The latter of which omits to acknowledge pre-existing anthropogenic disturbances and has the potential to skew monitoring of restoration and management efforts.

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