scholarly journals The influence of bait on remote underwater video observations in shallow-water coastal environments associated with the North-Eastern Atlantic

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9744 ◽  
Author(s):  
Robyn E. Jones ◽  
Ross A. Griffin ◽  
Stephanie R. Januchowski-Hartley ◽  
Richard K.F. Unsworth

The use of baited remote underwater video (BRUV) for examining and monitoring marine biodiversity in temperate marine environments is rapidly growing, however many aspects of their effectiveness relies on assumptions based on studies from the Southern Hemisphere. The addition of bait to underwater camera systems acts as a stimulus for attracting individuals towards the camera field of view, however knowledge of the effectiveness of different bait types in northern temperate climbs is limited, particularly in dynamic coastal environments. Studies in the Southern Hemisphere indicate that oily baits are most effective whilst bait volume and weight do not impact BRUV effectiveness to any great degree. The present study assesses the influence of four bait types (mackerel, squid, crab and no bait (control)) on the relative abundance, taxonomic diversity and faunal assemblage composition at two independent locations within the North-Eastern Atlantic region; Swansea Bay, UK and Ria Formosa Lagoon, Portugal. Two different bait quantities (50 g and 350 g) were further trialled in Swansea Bay. Overall, patterns showed that baited deployments recorded statistically higher values of relative abundance and taxonomic diversity when compared to un-baited deployments in Swansea Bay but not in Ria Formosa Lagoon. No statistical evidence singled out one bait type as best performing for attracting higher abundances and taxonomic diversity in both locations. Faunal assemblage composition was however found to differ with bait type in Swansea Bay, with mackerel and squid attracting higher abundances of scavenging species compared to the crab and control treatments. With the exception of squid, bait quantity had minimal influence on bait attractiveness. It is recommended for consistency that a minimum of 50 g of cheap, oily fish such as mackerel is used as bait for BRUV deployments in shallow dynamic coastal environments in the North-Eastern Atlantic Region.


2013 ◽  
Vol 64 (2) ◽  
pp. 91 ◽  
Author(s):  
Christian Hily ◽  
Jacques Grall ◽  
Laurent Chauvaud ◽  
Morgane Lejart ◽  
Jacques Clavier

Many autochthonous and alien macroinvertebrates of the intertidal zone are biocalcifiers, and the present study proposes a first assessment of their calcimass and their annual calcium carbonate (CaCO3) production at a regional scale, along 500 km of the coastline of Brittany, France, which represents a wide range of the rocky-shore habitats commonly encountered in the north-eastern Atlantic region. All sites considered together gave a mean calcimass estimate of 5327 g m–2. The corresponding mean CaCO3 gross production was 2584 g m–2 year–1. The net production (including dissolution) by biocalcification was 2384 g CaCO3 m–2 year–1. Estimations of CO2 production via both calcification and respiration were carried out in particular for the phylum Mollusca and for crustacean barnacles, dominating in terms of calcimass. Mean CO2 production obtained by summing CO2 fluxes related to net CaCO3 production and respiration for all sampled sites was 22.9 mol m–2 year–1. These results illustrate the significance of CO2 production during biogenic CaCO3 precipitation of intertidal invertebrates in such temperate coastal environment compared with tropical zones and the contribution of the shelves to the global CaCO3 budget.



Oceans ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 215-232
Author(s):  
Robyn E. Jones ◽  
Ross A. Griffin ◽  
Roger J. H. Herbert ◽  
Richard K. F. Unsworth

Baited remote underwater videos (BRUV) are popular marine monitoring techniques used for the assessment of motile fauna. Currently, most published studies evaluating BRUV methods stem from environments in the Southern Hemisphere. This has led to stricter and more defined guidelines for the use of these techniques in these areas in comparison to the North Atlantic, where little or no specific guidance exists. This study explores metadata taken from BRUV deployments collected around the UK to understand the influence of methodological and environmental factors on the information gathered during BRUV deployments including species richness, relative abundance and faunal composition. In total, 39 BRUV surveys accumulating in 457 BRUV deployments across South/South-West England and Wales were used in this analysis. This study identified 88 different taxa from 43 families across the 457 deployments. Whilst taxonomic groups such as Labridae, Gadidae and Gobiidae were represented by a high number of species, species diversity for the Clupeidae, Scombridae, Sparidae, Gasterosteidae and Rajidae groups were low and many families were absent altogether. Bait type was consistently identified as one of the most influential factors over species richness, relative abundance and faunal assemblage composition. Image quality and deployment duration were also identified as significant influential factors over relative abundance. As expected, habitat observed was identified as an influential factor over faunal assemblage composition in addition to its significant interaction with image quality, time of deployment, bait type and tide type (spring/neap). Our findings suggest that methodological and environmental factors should be taken into account when designing and implementing monitoring surveys using BRUV techniques. Standardising factors where possible remains key. Fluctuations and variations in data may be attributed to methodological inconsistencies and/or environment factors as well as over time and therefore must be considered when interpreting the data.



1942 ◽  
Vol 21 (8) ◽  
pp. 315
Author(s):  
Bowen ◽  
Vickery ◽  
Buchanan ◽  
Swallow ◽  
Perks ◽  
...  


Author(s):  
Sergey B. Kuklev ◽  
Vladimir A. Silkin ◽  
Valeriy K. Chasovnikov ◽  
Andrey G. Zatsepin ◽  
Larisa A. Pautova ◽  
...  

On June 7, 2018, a sub-mesoscale anticyclonic eddy induced by the wind (north-east) was registered on the shelf in the area of the city of Gelendzhik. With the help of field multidisciplinary expedition ship surveys, it was shown that this eddy exists in the layer above the seasonal thermocline. At the periphery of the eddy weak variability of hydrochemical parameters and quantitative indicators of phytoplankton were recorded. The result of the formation of such eddy structure was a shift in the structure of phytoplankton – the annual observed coccolithophores bloom was not registered.



Author(s):  
Phi Hung Cuong ◽  
Vu Van Anh

Income is an important indicator for assessing the level of economy development as well as identifying and assessing living standards. The population in Northeast border is poor, facilities are outdated, people’s life is difficult, but it hold great potentials for economic development. However, the region’s biggest challenge today is low living standards and high poverty rate. Differences in income and living standards across regions and strata tend to increase the gap. The sustainability of the trend of income increase and improvement of living standards of the population is not stable. As a result, the development of mountainous areas is dependent on poverty reduction solutions for ethnic minorities through the increase of incomes and improvement of market connectivity for ethnic minorities in mountainous areas.



Think India ◽  
2019 ◽  
Vol 22 (3) ◽  
pp. 186-192
Author(s):  
Dr. Oinam Ranjit Singh ◽  
Dr. Nushar Bargayary

The Bodo of the North Eastern region of India have their own kinship system to maintain social relationship since ancient periods. Kinship is the expression of social relationship. Kinship may be defined as connection or relationships between persons based on marriage or blood. In each and every society of the world, social relationship is considered to be the more important than the biological bond. The relationship is not socially recognized, it fall outside the realm of kinship. Since kinship is considered as universal, it plays a vital role in the socialization of individuals and the maintenance of social cohesion of the group. Thus, kinship is considered to be the study of the sum total of these relations. The kinship of the Bodo is bilateral. The kin related through the father is known as Bahagi in Bodo whereas the kin to the mother is called Kurma. The nature of social relationships, the kinship terms, kinship behaviours and prescriptive and proscriptive rules are the important themes of the present study.



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