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Perforation gun and cable are stuck underground, which often occurs in cable perforation. Whether the perforation cable gets stuck properly or not will not only affect the cost of accident treatment, sometimes even affect the success or failure of a well, and sometimes delay the best time of other well layout; Therefore, the unblocking and fishing technology of perforating gun is an important part of perforating operation. The fishing operation of perforating gun sticking can be divided into two categories: one is the fishing of cable, the other is the fishing of perforating gun body. The shape of fish falls into rope and tube. The stuck fishing work must accurately grasp: well condition data, fish falling situation, fishing tool combination, fish head situation, etc. Combined with the process of accident treatment, this paper studies and analyzes the fishing technology of perforating cable and perforating gun.

Fisheries are among the human activities that are most strongly affected by ongoing climate-related changes in the presence and abundance of fish species across the globe. The ecological and social repercussions of such changes for recreational fisheries are however still poorly understood. Here, we compare selected ecological and social dimensions of both recreational angling and spearfishing targeting the bluefish (Pomatomus saltatrix) in Italy. The bluefish has undergone a northward expansion in the region over the last 20–30 years, during which it reached new areas and increased in abundance. Using digital videos and their associated data published by both recreational anglers and spearfishers on YouTube we characterized ecological and social dimensions using a culturomics approach. Specifically, we focused on harvesting patterns, social engagement and sentiments related to the bluefish. Our study revealed four major results: (1) similar harvesting patterns (i.e., declared mass and seasonal upload patterns) related to videos by both recreational anglers and spearfishers; (2) higher social engagement (i.e., number of views and likes) for videos by recreational anglers than spearfishers; (3) differences in themes of discussion, with anglers being mainly interested in fishing strategy and gears and spearfishers being more interested in fishing actions shown on the videos; (4) positive and negative sentiments of both recreational anglers and spearfishers towards the invasiveness and aggressiveness of the species. The latter represents an interesting trade-off associated with recreational fishing of the bluefish: it is perceived as an invasive species, but it is also a valued target fish because its voracity contributes to the quality of the recreational fishing experience. Our study showcases the value of exploring social media and associated data to better understand the ecological and human dimensions of marine recreational fisheries in relation to distributional range shifts of species associated with climate change.

Coral reefs are subjected to unprecedented levels of disturbance with population growth and climate change combining to reduce standing coral cover and stocks of reef fishes. Most of the damage is concentrated in shallow waters (<30 m deep) where humans can comfortably operate and where physical disturbances are most disruptive to marine organisms. Yet coral reefs can extend to depths exceeding 100 m, potentially offering refuge from the threats facing shallower reefs. We deployed baited remote underwater stereo-video systems (stereo-BRUVs) at depths of 10–90 m around the southern Mariana Islands to investigate whether fish species targeted by fishing in the shallows may be accruing benefits from being at depth. We show that biomass, abundance and species richness of fishery-targeted species increased from shallow reef areas to a depth of 60 m, whereas at greater depths, a lack of live coral habitat corresponded to lower numbers of fish. The majority of targeted species were found to have distributions that ranged from shallow depths (10 m) to depths of at least 70 m, emphasising that habitat, not depth, is the limiting factor in their vertical distribution. While the gradient of abundance and biomass versus depth was steepest for predatory species, the first species usually targeted by fishing, we also found that fishery-targeted herbivores prevailed in similar biomass and species richness to 60 m. Compared to shallow marine protected areas, there was clearly greater biomass of fishery-targeted species accrued in mesophotic depths. Particularly some species typically harvested by depth-limited fishing methods (e.g., spearfishing), such as the endangered humphead wrasse Cheilinus undulatus , were found in greater abundance on deeper reefs. We conclude that mesophotic depths provide essential fish habitat and refuge for fishery-targeted species, representing crucial zones for fishery management and research into the resilience of disturbed coral reef ecosystems.

Recreational spearfishing is a fishing method that occurs globally, yet receives considerably less attention in the scientific literature relative to other recreational fishing methods, such as angling. Lack of scientific information on spearfishing may negatively affect the development and management of marine recreational fisheries. We conducted a systematic review of 102 peer-reviewed papers published between 1967 and 2022 pertaining to marine recreational spearfishing. Based on this literature review, we provide an overview of key insights across social, economic, and ecological dimensions of marine recreational spearfishing. While spearfishers represent less than 5% of marine recreational fishers, the participants are younger and may differ from recreational anglers in their motivations, with suggestions of increased well-being generated from a close connection with the sea during underwater fishing. Recreational spearfishers mostly target species of moderate to high levels of vulnerability that are mid to high trophic level carnivores. Though spearfishers can deliberately target larger individuals of exploited populations, this is not a generalizable pattern. Despite a growing body of research on the ecological impacts of marine recreational spearfishing, there is limited knowledge of these effects and their mechanisms across biological levels of organization (e.g., individual, population, community and ecosystem) compared with those of other fishing methods. Recreational spearfishers can contribute to advances in marine ecological knowledge, and inclusive participatory management could represent a key step towards transformative sustainable development of marine recreational spearfishing. Throughout the review, we identify gaps in the research and areas where future research is needed to better inform the socio-economic importance, ecosystem impacts and future management of marine recreational spearfishing.

Inshore coral reefs support unique ecosystems that are subject to a variety of threats and disturbances. Marine protected areas are powerful conservation tools and often include zones which vary in the level of fishing restriction, including fully protected (no-take) zones, partially protected zones (limited fishing), and less protected “open” fishing zones. Here, we compare outcomes from fully protected, partially protected, and “open” fishing zones on inshore fringing reefs of the Great Barrier Reef with a history of cyclone-induced habitat disturbance. Biomass of target and non-target fish groups, along with the coral cover and structural complexity of benthic habitats, was compared among zones. There was a strong positive effect of full protection from fishing on targeted fish biomass, and a comparatively modest effect of partial protection, even in areas where spearfishing was prohibited. Fully protected zones supported more than three times the biomass of highly targeted coral trout (Plectropomus spp.) compared to open fishing zones, and more than twice the biomass observed in partially protected zones. Similar outcomes occurred for primary targets collectively; conversely, there were no zoning-related differences for non-target fishes. Structural complexity was a consistent positive driver of fish biomass for all fish groups and among all zones. Notably high target fish biomass occurred at NTMR sites with the highest structural complexity, highlighting the importance of both habitat and protection in supporting population hotspots for targeted reef fishes.

The Xisha Islands constitute the largest coral reef archipelago on the northern margin of the Coral Triangle and are the largest coral reef archipelago among the islands in the South China Sea. This study employed various survey methods including underwater spearfishing, gill netting, handline fishing, longlining fishing, underwater visual surveys, and environmental DNA (eDNA). Additionally, historical data from 1956 to 2023 were reviewed to comprehensively analyze the adaptation characteristics of the fish community structure in the Xisha Islands. The Xisha Islands have documented a total of 874 coral reef fish species, categorized into 27 orders, 102 families, and 337 genera. Of these species, the order Perciformes demonstrated the greatest species richness, which represents 71.05% of the total fish species documented. The structure of coral reef fish communities in the Xisha Islands has undergone significant changes. Firstly, a significant decline in the population of large-sized and carnivorous fish species was observed. The proportion of large-sized fish species diminished by 6.02% (62 species), and the medium-sized fish species saw a reduction of 3.09% (51 species). In contrast, there was a surge of 9.12% in the small-sized fish species population. The carnivorous fish species experienced a decrease of 4.73% (102 species), while an increase was noted in the population of herbivorous and omnivorous fish species. Secondly, the numbers of orders, families, and genera have also significantly decreased, with noticeable declines in the average taxonomic distinctness (Delta +), the variation taxonomic distinctness (Lambda +), functional richness (FRic), and quadratic entropy (RaoQ). Thirdly, the similarity between fish species at different time periods is relatively low. Among different functional groups, large-sized and carnivorous fish species exhibit the lowest similarity, whereas herbivorous fish species exhibit the highest. The turnover of live coral fish species is also evident. Overall, the coral reef fish in the Xisha Islands are showing a trend towards herbivory, miniaturization, and a simplification in species composition and functionality. This study contributes to a better understanding and prediction of the adaptation trends in fish species composition in the Xisha Islands, which is crucial for ensuring the ecosystem services of coral reefs and for the conservation and restoration of ecosystems.

Parrotfish (Scarus sp.) is a coral reef fish which has high economic value. The increasing market demand for Scarus sp. has led to an increasing pressure on fishing. Scarus sp. fish are caught using spearfishing gear. Uncontrolled exploitation activities can disrupt fish resources. The purpose of this study was to determine the status of Scarus sp.'s management and resource utilization related to the given resource domain and fishing techniques, based on the Ecosystem Approach to Fisheries Management (EAFM) method. Data collection was carried out through field observations and interviews with 35 spearfishing fishermen in Karimunjawa Island, between May-June 2024. The results of the study indicated that the status of Scarus sp. fisheries was in the good or moderate category, given the resource domain and fishing techniques, showing a composite value of 64.23 with an indicator score of 2.08. Although the assessment, based on the resource domain and fishing techniques, shows that the sustainability status of parrotfish fisheries management and resource utilization are close to optimal, these can be improved through regulating fishing seasons, conducting socialization of information on stock conditions and sizes of fish caught. These can be achieved by controlling parrotfish fishing activities and conducting collaborative supervision and community participation.

Partially Protected Areas (PPAs) are a widely-used management tool, yet comparatively little is known about their effectiveness compared to more commonly studied No-Take Marine Reserves (NTMRs). Here, we examine the efficacy of two kinds of PPAs (with and without spearfishing) within the Great Barrier Reef Marine Park (GBRMP) that are subject to a range of fishing limitations, and assess their utility as a marine park zoning and fisheries management tool. Fish abundance, size, and habitat composition were compared inside PPAs and NTMRs on inshore reefs of the central GBR. Fish abundances were lower inside PPAs relative to adjacent NTMRs for primary fishing targets, with no detectable effects for secondary targets and non-targets, or for species richness. Fish assemblages differed amongst zones, but these variations were minor compared to regional variations in species composition. Partially Protected Areas supported 46%–69% of the relative abundance of total primary targets compared to adjacent NTMRs, with no evident increase in abundance in zones where spearfishing was prohibited. There were no reductions in the size of two key target species: coral trout (Plectropomus spp.) and stripey snapper (Lutjanus carponotatus) inside PPAs, and only stripey snapper had significant reductions in abundance inside PPAs compared to NTMRS. Habitat and biophysical characteristics (especially topographic complexity) were strong drivers of fish abundance, but the relative influence of zone was greater for target species compared to non-targets. This study provides novel data on PPAs and highlights their utility as a spatial management tool in contributing to conservation and fisheries management goals.

We show that marine recreational spearfishers voluntarily organize bottom-up conservation actions. The main goals of these actions are to provide support to research in monitoring fish assemblages, tracking biological invasions or mitigating impacts on the environment, such as those stemming from pollution and littering. We show that such initiatives started more than 20 years ago and are now facilitated by social media networking. We argue that the emergence of bottom-up conservation actions in marine recreational spearfishers should be encouraged, supported and integrated into participatory management plans. This is important to mitigate the potential negative impacts of marine recreational spearfishing and to catalyse broader civil actions for conservation of marine ecosystems.

The impact of recreational fishing on fish stocks was neglected for many years as it was considered minor and insignificant. Despite the increasing assessment of the impact of recreational fishing, little effort is made to effectively and systematically collect catch and effort data from recreational fishing and integrate them into official fishery statistics. The aim of this study is to provide the first empirical investigation to quantify the impact of spearfishing on coastal fish communities in the eastern Adriatic. In Croatia, continuous monitoring of spearfishing competitions started in 2005, but, in 2012, the rules for the competitions were changed, and the species and quantities per species were restricted. For the purpose of this analysis, only data collected during the seven-year period from 2005 to 2011 were used, which included a total of 46 competitions in which spearfishers fished without any limitations, as later data were not comparable. These data can provide a robust estimation of the impact of spearfishing on coastal communities. Instead of a general approach, future studies should adopt a species-specific approach. Compared to the results on the impacts of other fishing methods, the obtained results are useful for researchers, managers, and also policy makers to sustainably manage coastal ecosystems and the associated ecosystems services.