scholarly journals Impact of mechanized clam dredging on the discarded megabenthic fauna on the Catalan coast (NW Mediterranean)

2021 ◽  
pp. 1-9
Author(s):  
Marc Baeta ◽  
Claudia Rubio ◽  
Françoise Breton
Keyword(s):  
Small Scale ◽  
Fishing Activity ◽  
Lethal Damage ◽  
Catalan Coast ◽  
Nw Mediterranean ◽  
Chamelea Gallina ◽  
Level Scale ◽  
Nw Mediterranean Sea ◽  
The Impact ◽  
Partial Damage

Abstract There is an important small-scale fishery using mechanized dredges and targeting clams (mainly wedge clam Donax trunculus and striped venus clam Chamelea gallina) along the Catalan coast (NW Mediterranean Sea). This study evaluated for the first time the discards and impact of mechanized clam dredging on the Catalan coast. To this end, three surveys were performed on board standard clam vessels (September and November 2016 and January 2017). Surveys were conducted in the three main clam fishing areas (Rosas Bay, South Barcelona and Ebro Delta). The composition of discards and the impact caused to discarded species was assessed using a three-level scale (undamaged; minor or partial damage; and lethal damage). Our study revealed that a large proportion of the catch (between 67–82% weight) is discarded. Even though about 63% of the discarded species were undamaged, 11% showed minor or partial damage and 26% lethal damage. Infaunal and epifaunal species with soft-body or fragile shells were the most impacted by the fishing activity (e.g. the sea urchin Echinocardium mediterraneum (~89%) and the bivalve Ensis minor (~74%)). Our results showed different levels of impact by target species and fishing area.

scholarly journals First description of a new worm bait fishery in the NW Mediterranean Sea

2019 ◽  
Vol 20 (2) ◽  
pp. 302
Author(s):  
MARC BAETA ◽  
AROA NAVARRETE ◽  
MANUEL BALLESTEROS
Keyword(s):  
Mediterranean Sea ◽  
Economic Value ◽  
Small Scale ◽  
Recreational Fishing ◽  
Recreational Fisheries ◽  
Fishing Activity ◽  
Fishing Sector ◽  
Quality Product ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

Most commercial clam stocks in the NW Mediterranean Sea have collapsed over the last few decades and, as a result, most clam dredge fishermen have been forced to leave the fishing sector. Recently, in order to sustain their economic activity, some fishermen have modified dredges to target sea worms to sell as bait for recreational fisheries. This study provides the first information about this new worm bait fishery on the Catalan Maresme coast (NE Spain). The local administration has regulated only a few aspects of the fishery: users (2 boats), geographical limits (40 km; between 0-7 m depth), fishing time (6:00-14:00) and dredge design (the same as those used for smooth clams but with interior structures to retain worms and an open back). Fishing activity takes place throughout the year. Fishermen target three worm bait species: Sigalion squamosus, Ophelia neglecta and Halla parthenopeia. A mean of 233.37 individuals of S. squamosus, 167.93 of O. neglecta and 2.17 of H. parthenopeia are gathered per boat and day. Worm baits are sold directly to local recreational fishing shops as a quality product at the highest prices on the market. This fishery has a high social and economic value for the Maresme coast, helping to maintain small-scale fishermen jobs with an economic benefit similar to clam fishing.

scholarly journals Impact of COVID-19 Lockdown on the Fisheries Sector: A Case Study from Three Harbors in Western India

2021 ◽  
Vol 13 (2) ◽  
pp. 183
Author(s):  
Ram Avtar ◽  
Deepak Singh ◽  
Deha Agus Umarhadi ◽  
Ali P. Yunus ◽  
Prakhar Misra ◽  
...  
Keyword(s):  
Global Economy ◽  
Emergency Situation ◽  
Support Vector ◽  
Small Scale ◽  
Western India ◽  
Western Coast ◽  
Land Area ◽  
Fishing Activity ◽  
South West Monsoon ◽  
The Impact

The COVID-19 related lockdowns have brought the planet to a standstill. It has severely shrunk the global economy in the year 2020, including India. The blue economy and especially the small-scale fisheries sector in India have dwindled due to disruptions in the fish catch, market, and supply chain. This research presents the applicability of satellite data to monitor the impact of COVID-19 related lockdown on the Indian fisheries sector. Three harbors namely Mangrol, Veraval, and Vankbara situated on the north-western coast of India were selected in this study based on characteristics like harbor’s age, administrative control, and availability of cloud-free satellite images. To analyze the impact of COVID in the fisheries sector, we utilized high-resolution PlanetScope data for monitoring and comparison of “area under fishing boats” during the pre-lockdown, lockdown, and post-lockdown phases. A support vector machine (SVM) classification algorithm was used to identify the area under the boats. The classification results were complemented with socio-economic data and ground-level information for understanding the impact of the pandemic on the three sites. During the peak of the lockdown, it was found that the “area under fishing boats” near the docks and those parked on the land area increased by 483%, 189%, and 826% at Mangrol, Veraval, and Vanakbara harbor, respectively. After phase-I of lockdown, the number of parked vessels decreased, yet those already moved out to the land area were not returned until the south-west monsoon was over. A quarter of the annual production is estimated to be lost at the three harbors due to lockdown. Our last observation (September 2020) result shows that regular fishing activity has already been re-established in all three locations. PlanetScope data with daily revisit time has a higher potential to be used in the future and can help policymakers in making informed decisions vis-à-vis the fishing industry during an emergency situation like COVID-19.

scholarly journals Ecological traits, genetic diversity and regional distribution of the macroalga Treptacantha elegans along the Catalan coast (NW Mediterranean Sea)

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Alba Medrano ◽  
Bernat Hereu ◽  
Simone Mariani ◽  
João Neiva ◽  
Marta Pagès-Escolà ◽  
...  
Keyword(s):  
Regional Distribution ◽  
Current Status ◽  
Depth Range ◽  
Northern Coast ◽  
High Turnover ◽  
Catalan Coast ◽  
Demographic Traits ◽  
Nw Mediterranean ◽  
Unique Source ◽  
Nw Mediterranean Sea

Abstract The widespread decline of canopy-forming macroalgal assemblages has been documented in many regions during the last decades. This pattern is often followed by the replacement of structurally complex algal canopies by more simplified habitats (e.g., turfs or sea urchin barren grounds). Against all odds, the fucoid Treptacantha elegans, a large Mediterranean brown macroalga, broadened its depth range to deeper and exposed environments and displayed an unexpected range expansion along the northern coast of Catalonia over the last two decades. Here, we reconstruct the spread of T. elegans in time and space and unravel ecological and demographic traits such as population dynamics and genetic patterns to provide a comprehensive and integrated view of the current status and geographical expansion for this species. Fast-growing dynamics, early fertile maturity, and high turnover rate are the main competitive advantages that allow the exposed populations of T. elegans to colonize available substrata and maintain dense and patchy populations. We also provided evidence that the deeper and exposed populations of T. elegans constitute a single group across the Catalan coast, with little genetic differentiation among populations. This seems to support the hypothesis of a unique source of spread in the last decades from the Medes Islands No-Take Zone towards both southern and northern waters.

scholarly journals IMPACT OF FUEL SUBSIDIES ON FISHERMEN INCOME AN EMPIRICAL STUDY OF SMALL-SCALE FISHERMEN IN KEDAH AND PERLIS

2020 ◽  
Vol 2 (No.1) ◽  
pp. 35-47
Author(s):  
Wan Hafidzatul Akmal Mgt Husain ◽  
Jamal Ali ◽  
Amizam Arzemi
Keyword(s):  
Socioeconomic Background ◽  
Small Scale ◽  
Monthly Income ◽  
Group Discussions ◽  
Fishing Activity ◽  
Explanatory Variables ◽  
Incentive Value ◽  
Fuel Subsidies ◽  
The Cost ◽  
The Impact

Even though fuel subsidy can give more profit to the fisheries sector, it also has drawbacks to the ecosystem that tends to lead to overcapacity. This study investigated the impact of fuel subsidies on the income of fishermen operating in Zone A and Zone B in Kedah and Perlis. Focus group discussions with fisherman association committees were conducted to understand the issues related to fuel subsidy. The regression analysis method was used to examine the relationship between the fishermen’s monthly income and various explanatory variables, such as oil subsidy received by the fishermen, the incentive value of catch received, the monthly allowance, the location of fishing activity, and the socioeconomic background of fishermen. The result of the study revealed that Boat B fishermen gained more benefits from the implementation of fuel subsidized policy than Boat A fishermen because the former used larger boat sizes and better fishing gear. In addition, variables, such as fuel subsidy, operating costs, and duration of fishing hours, influenced fishermen's income. Although fuel subsidies may contribute toward overfishing, fuel subsidy is still needed by small-scale fishermen since it can reduce the cost of fishing activities and thus increase their monthly income. This research indicates that it is important to understand the contribution of fuel as the total cost of fishing activities and how fuel subsidies can reduce these costs to improve the income of fishermen in the study area.

scholarly journals Classifying compound coastal storm and heavy rainfall events in the north-western Spanish Mediterranean

2020 ◽  
Author(s):  
Marc Sanuy ◽  
Tomeu Rigo ◽  
José A. Jiménez ◽  
M. Carmen Llasat
Keyword(s):  
Extreme Events ◽  
Heavy Rainfall ◽  
Time Window ◽  
Weather Conditions ◽  
Flash Floods ◽  
Coastal Storms ◽  
The North ◽  
Catalan Coast ◽  
Nw Mediterranean ◽  
The Impact

Abstract. The Northwest (NW) Mediterranean coastal zone is a populous and well-developed area in which the impact of natural hazards like flash floods and coastal storms can result in frequent and significant damages. Although the occurrence and impacts of such hazards have been widely covered, few studies have considered their combined impact on the region, which would result in more damage. Within this context, this study analyses the occurrence and characteristics of compound extreme events of heavy rainfall episodes (as a proxy for flash floods) and coastal storms (using the maximum significant wave height) along the Catalan coast as a paradigm of the NW Mediterranean. Two different types of events are considered: multivariate, in which the two hazards occur at the same location, and spatially compounding, in which they occur within the same limited time window and their impacts accumulate at distinct and separate locations. The analysis is regionally performed along a coastline extension of about 600 km by considering seven coastal sectors and their corresponding river catchment basins. Once the compound events are analysed, the synoptic atmospheric pressure fields are analysed to determine the prevailing weather conditions that generated them. Finally, a Bayesian network is used to fully characterise these events over the territory. The obtained results show that the NW Mediterranean, represented by the Catalan coast, has a high probability of experiencing compound extreme events (3.4 events per year). Despite the relatively small size of the study area (600 km of coastline), there are significant variations in the event characteristics along the territory, with the most frequent type being spatially compound, except in the northernmost sectors where multivariate events dominate. These northern sectors also present the highest correlation in the intensity of both hazards. Three representative synoptic situations have been identified as dominant for the occurrence of these events, with different relative importance levels of the compounding drivers (rainfall and waves) and different distributions of impacts across coastal basins. Overall, the results indicate that heavy rainfall has the more significant damage impact despite the wave damage having a larger spatial reach.

scholarly journals Classifying compound coastal storm and heavy rainfall events in the north-western Spanish Mediterranean

2021 ◽  
Vol 25 (6) ◽  
pp. 3759-3781
Author(s):  
Marc Sanuy ◽  
Tomeu Rigo ◽  
José A. Jiménez ◽  
M. Carmen Llasat
Keyword(s):  
Extreme Events ◽  
Heavy Rainfall ◽  
Time Window ◽  
Flash Floods ◽  
North West ◽  
Coastal Storms ◽  
The North ◽  
Catalan Coast ◽  
Nw Mediterranean ◽  
The Impact

Abstract. The north-west (NW) Mediterranean coastal zone is a populous and well-developed area in which the impact of natural hazards like flash floods and coastal storms can result in frequent and significant damages. Although the occurrence and impacts of such hazards have been widely covered, few studies have considered their combined impact on the region, which would result in more damage. Within this context, this study analyses the occurrence and characteristics of compound extreme events of heavy rainfall episodes (as a proxy for flash floods) and coastal storms (using the maximum significant wave height) along the Catalan coast as a paradigm of the NW Mediterranean. Two different types of events are considered: multivariate, in which the two hazards occur at the same location, and spatially compounding, in which they occur within the same limited time window, and their impacts accumulate at distinct and separate locations. The analysis is regionally performed along a coastline extension of about 600 km by considering seven coastal sectors and their corresponding river catchment basins. Once the compound events are analysed, the synoptic atmospheric pressure fields are analysed to determine the prevailing weather conditions that generated them. Finally, a Bayesian network is used to fully characterize these events over the territory. The obtained results show that the NW Mediterranean, represented by the Catalan coast, has a high probability of experiencing compound extreme events. Despite the relatively small size of the study area, there are significant variations in the event characteristics along the territory, with the most frequent type being spatially compound, except in the northernmost sectors where multivariate events dominate. These northern sectors also present the highest correlation in the intensity of both hazards. Three representative synoptic situations have been identified as dominant for the occurrence of these events, with different relative importance levels of the compounding drivers (rainfall and waves) and different distributions of impacts across coastal basins. Overall, results obtained from specific events indicated that heavy rainfall is related to the most significant impacts despite having a larger spatial reach.

On the joint impact of marine (storms) and terrestrial (flash floods) extreme events along the Catalan coast (NW Mediterranean)

2020 ◽  
Author(s):  
Marc Sanuy Vazquez ◽  
Montserrat Llasat-Botija ◽  
Tomeu Rigo ◽  
Jose A. Jiménez ◽  
M. Carme Llasat
Keyword(s):  
Coastal Zone ◽  
Extreme Events ◽  
Urban Areas ◽  
Flash Floods ◽  
Climatic Conditions ◽  
Catalan Coast ◽  
Synoptic Conditions ◽  
Nw Mediterranean ◽  
Using Data ◽  
The Impact

<p>The Mediterranean coastal zone is a hotspot to the impact of extreme events due to the combination of high values at exposure (concentration of population, large urban areas, infrastructures), large vulnerability (natural protection provided by beaches decreasing due to coastal erosion) and presence of extreme hydro-meteorological events of marine (storms) and terrestrial (flash floods) origins. The Catalan coast (NE Spain) can be considered a paradigm of Med hotspots. On one hand, due to its climatic conditions, orography and land use, flash floods are one of the main causes of inundation risks in the coastal fringe, inducing numerous damages and even casualties (e.g. Llasat et al. 2013). On the other hand, coastal damage associated to the impact of marine storms have been increasing during the last decades along this coast (Jiménez et al. 2012). However, existing studies have not analysed their joint impact to assess the most hazardous conditions, when the coastal zone would be subjected to the combined action of both types of extreme events.</p><p>Within this context, this works analyses the combined presentation of extreme events of terrestrial (flash floods) and marine (storms) origin in the Catalan coast. First, extreme events causing significant damage (based on reported damages, insurance costs and casualties) along the coast were identified for the period 1981-2014. 69 events were identified and classified according their origin (marine and/or terrestrial). Each event was characterized in terms of their marine (wave height, period, direction, storm duration) and rainfall characteristics. Since the coastline length is about 600 km, these events verify at specific locations. To cover this spatial variability, storms were locally characterized by using data from existing rain gauges and radar stations along the territory as well as hindcasted wave conditions along the entire coastal fringe. To fully characterize these events, synoptic conditions were also recorded.</p><p>From this, first, we directly obtained the corresponding marginal probabilities of each event. Then, compound frequencies were assessed and compared to the marginal ones. Finally, we identified synoptic situations with higher probability of associated compound hazards and bound the range of corresponding wave and rain conditions. By jointly considering the location where they verified, we identify coastal areas (and corresponding geomorphologic conditions) with higher probabilities of suffering damages due to impact of compound extreme events.</p><p>This work was carried out within the framework of the M-CostAdapt (CTM2017-83655-C2-1-R) research project, funded by the Spanish Ministry of Economy and Competitiveness (MINECO/AEI/FEDER, UE).</p><p>Jiménez et al. 2012. Storm-induced damages along the Catalan coast (NW Mediterranean) during the period 1958–2008. Geomorphology 143, 24-33.</p><p>Llasat et al. 2013.  Towards a database on societal impact of Mediterranean floods within the framework of the HYMEX project. NHESS, 13, 1337-1350.</p>

scholarly journals Effect of Coronavirus on Aquaculture in Oyo state, Nigeria

2021 ◽  
Vol 13 (11) ◽  
pp. 153
Author(s):  
Selorm Omega ◽  
Alexander T. K. Nuer ◽  
Enoch Ametepey
Keyword(s):  
Coping Strategies ◽  
Survey Design ◽  
Health Concern ◽  
Primary Data ◽  
Small Scale ◽  
Cross Sectional Survey ◽  
Fishing Activity ◽  
Cross Sectional ◽  
Small Scale Farmers ◽  
The Impact

Coronavirus 2019 is a global health concern that has left most countries in a state of severe economic meltdown. Scientific research has been down on the virus and its impact on various sectors but that of the Nigerian aquaculture industry has been missing. This paves the way for this research to aim at bridging this gap by looking at the perception of fish farmers on the influence of coronavirus on their activities, the challenges they face during the period of the virus, and the coping strategies adopted to mitigate the impact of the virus. The research used cross sectional survey design with the sample size being 11 fish farmers living in Oyo state, Nigeria. Homogeneous purposive sampling was used and primary data collected through the use of google form. The data collected was analysis using SPSS version 25.0. The result of the analysed data showed that: on socioeconomic characteristics; the majority of the respondent reported that Coronavirus has had an effect on their fishing activity and they were mostly small scale farmers with catfish being the predominate fish farmed. The majority of fish farmers perceived demand decline, high cost of production, fish being more expensive, and reduction of manpower on the farm due to lockdown measures. Reduction in walk-in customers to the farm was revealed as the major challenge posed by the pandemic, while the inability to get technical support as least. On coping strategies adopted, it was revealed that farmers have resorted to the development of their own feed.

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