Gear Categories Research Articles

Lithic projectile technology in the western Late Epigravettian: The case study of north-eastern Italy

Projectile implements are one of the most frequent transformed lithic blanks within the Upper Paleolithic assemblages. Since the first taxonomic studies, their morphological variability has been used as primary fossil director to define specific regional trends and diachronic phases. However, an exhaustive analysis of manufacturing methods and techniques applied to shape this gear category is extremely rare. In fact, during the Late Epigravettian, except for a certain typological variability, the lack of detailed studies resulted in an apparent homogeneity in armatures production. In this paper, a technological and traceological approach applied to reconstruct the whole chaîne opératoire of armatures manufacture in three Northern Italian sites dated between 17,000 and 12,000 cal BP demonstrates important variations in how projectile implements are fashioned, concerning shape, production methods and retouch techniques. Moreover, a large-scale comparison suggests how renewals in projectile implements production in North-Eastern Italy may result from long-distance connections between human groups over the western Late Epigravettian territory.

Why, and where, is commercial fishing gear lost? A global review and case study of Pacific Canada

Derelict fishing gear is a global problem, damaging marine ecosystems via habitat degradation and trapping marine life, thereby impacting fisheries. We conducted a global review of reasons for commercial gear loss, and used the findings to design a survey focused on coastal British Columbia (BC), Canada. We conducted dockside and on-line surveys of commercial fishers to record their experiences with lost gear across net, line, and trap gear types. The most common reasons for gear loss from the global review were interactions with other fishing vessels and their gear, marine weather, and snagging on submerged features. Survey results of 29 fishers in BC indicated that snagging gear on rough substrate was the most important reason for loss across all gear categories, followed by seafloor type. Other reasons for gear loss varied by net, line, and trap gear type. Understanding reasons for gear loss is important to reduce losses.

Spesifikasi dan Identifikasi Hasil Tangkapan Garok Rajungan di Pelabuhan Perikanan Pantai (PPP) Bondet Kabupaten Cirebon, Jawa Barat

Crayfish (Portunus pelagicus) is the leading export commodity of Indonesian fishermen. The increasing demand for exports and high selling prices have made fishermen at the Bondet Beach Fishing Port, Cirebon Regency, use garok crabs to maximize their catch. The purpose of this study was to identify tool specifications, catch yields, selectivity and productivity of garok crab fishing gear operated at the Bondet Coastal Fishery Port, Cirebon Regency, West Java. The research was carried out in April – June 2021. The method used was a case study method with quantitative descriptive analysis to determine the specifications of the tools and catches taken by interviewing fishermen. The results showed that the crab claws were included in the dredge gear category. Its components consist of body mouth, garok, frame, nets, and ropes of various sizes. The main catch of garok crab in Cirebon Regency consists of small crab (Portunus pelagicus), and by-catch in the form of shellfish, shrimp, cuttlefish, and demersal fish, with a total of 14 species. This tool is classified as non-selective because of the small size of the bag mesh construction (30 mm) so that this tool catches many species with large and small size fish caught. The average catch obtained from 5 trips was 23.8 kg, with the lowest catch on the 2nd trip, which was 19.7 kg and the highest on the 5th trip, which was 31.3 kg, while the average sweep area was 0.0040 km2 with an average productivity of 3.97 kg/hour and the highest catch rate value was obtained on the 5th trip, which was 5.21 kg/hour, while the lowest catch rate was found on the second trip, which was 3.28 kg/hour.

Analysis of Environmentally Semi Trammel Net based on Code of Conduct Responsibilities Fisheries (CCRF) in Cirebon Waters

All fishing actors are required to use environmentally friendly fishing gear. The aim is to maintain the condition of fishery resources and their habitat, as well as to maintain the safety of fishermen and consumers. The research was conducted in February - April and August - September 2020 in Cirebon Regency, West Java Province. The research objective was to determine the status of the shrimp nets used by fishermen in Cirebon waters. The research method used is the survey method. Data analysis using weighting method on 9 criteria for environmentally friendly fishing gear based on Code 0f Conduct Responsibilities Fisheries (CCRF). Based on the research results, the semi trammel net used by Cirebon fishermen are included in the environmentally friendly fishing gear category with a score of 30.54.

Identification of Specifications and Catches of Sea Cucumber Dredge Gear in Cirebon Regency

Sea cucumbers (Holothuria sp) are a leading export commodity for Indonesian fishermen. The increase in the selling price and demand for sea cucumbers in 2018 made fishermen in Cirebon Regency modify the fishing gear to maximize the catch of sea cucumbers which is called the sea cucumber dredge gear. The purpose of this research is to identify the specifications of the gear, catch, selectivity and productivity of the sea cucumber dredge gear operated in Cirebon Regency, West Java. The research was carried out in July 2019 - September 2020 in Gebang Mekar District. Fishing gear measurements were carried out along the fishing village of Gebang Mekar Village. The method used is a case study method with quantitative descriptive analysis to determine the specifications of the fishing gear and catches taken by interviewing fishermen. The results showed that sea cucumber dredge gear was included in the dredge gear category. The components consist of a mouth, a hook, a frame, a net, and a rope of varying sizes. The materials used are iron and stainless steel, weighing up to 50 kg. The main catch of sea cucumber in Cirebon Regency consists of Phylloporus sp or ondol - ondol and bycatch in the form of several demersal fish, with a total of 7 species. This fishing gear is classified as not selective because of its construction which has a net with a small mesh size (2-5 inches) so that this fishing gear captures many species of different sizes and the results of the calculation of the proportion show that bycatch has a percentage of 74,75%.

IDENTIFIKASI ALAT PENANGKAPAN IKAN RAMAH LINGKUNGAN BERBASIS CCRF DI KABUPATEN PIDIE, ACEH

Pidie district is one of the producers of capture fisheries in Aceh Province with a number of fishermen reaching 1,019. Sea fishing activities are open access causing concern to the stock of fish resources in the waters. Many fishing operations that use fishing gear that are not environmentally friendly if not managed properly will cause fish resources to decline or overfishing. This study aims to identified environmentally friendly fishing tools based on the Code of Conduct for Responsible Fisheries (CCRF) in Pidie District. This research was conducted in March 2019 in the waters of Pidie District. Data collection was done by interview and direct observation in the field. Analysis of the environmental friendliness of fishing gear based on weighting the score with the Analysis Hiercy Process (AHP) method. The results showed that the fishing gear included in the category of very environmentally friendly, namely; handline, longline, gillnet, and purse seine. While the fishing gear category is not environmentally friendly, namely; Modified beach seine and beach seine.

Trawling in the Mediterranean: An Exploration of Empirical Relations Connecting Fishing Gears, Otterboards and Propulsive Characteristics of Fishing Vessels

Fishing pressure is often expressed in terms of vessel’s physical attributes, like tonnage and engine power, while a common definition of fishing capacity identifies vessel size as a convenient proxy for the size of gear used. Nevertheless, these definitions remain arguable, and the refinement of these fishing descriptors is increasingly receiving growing consideration. A stronger understanding of the relationship between the standard measures of effort and capacity and fishing mortality remains a primary objective, followed by the need to overcome a traditional approach that simply describes effort, capacity and mortality as linearly related, conferring to larger vessels a greater fishing power. In this perspective, the analysis of trawls’ technical features in relation with the size and power of the vessel might constitute an essential step. This study specifically investigated a collection of trawl gears technical specifications collected by CNR-IRBIM, Ancona. The dataset used includes records from several Mediterranean fisheries, and involves three trawling techniques, including single trawl, twin trawl and pair trawling, and diverse trawling gear categories, comprising demersal/bottom 2-panel trawls (OTB2), demersal/bottom 4-panel trawls (OTB4), pelagic 4-panel trawls (PTM4), semi-pelagic 2-panel trawls (OTM2), semi-pelagic 4-panel trawls (OTM4), and Mediterranean bottom beam trawl (TBB). We analyzed and described the relationships between vessels’ technical features (LOA, towing force, engine power), some among the main trawl-metrics (headline length, footrope length, trawl length, square width; fishing circle) and otterboard’s technical features (height, width, projected area) in the attempt to enhance fishing capacity definition through the inclusion of the fishing gear deployed. Self-Organizing maps were used to explore the empirical relationships among different parts of the fishing trawl gears, as well as between some of these parts and the otterboard size and the engine power of the vessel.

Reconstructing global marine fishing gear use: Catches and landed values by gear type and sector

The interaction between fishing gears and the marine environment define ‘fisheries,’ and the effect of gears on marine ecosystems and fish stocks has been the source of much debate. Here, we present the first summary of globally reconstructed fisheries catches by major gear categories for 1950–2014. We used the Sea Around Us reconstructed global catch database that accounts for reported and unreported fisheries catches, and associated all catches to a fishing gear category. We assigned all industrial (i.e., large-scale) fisheries catches to industrial gear categories by fishing country, taxon, year and the area of fishing. Additionally, we derived catches by individual small-scale gear types for the most-important small-scale fishing countries in each of nine regions around the world, and applied their gear use to similar countries in each of the regions, to serve as a preliminary small-scale catch-by-gear assignment that can be improved upon over time. The combination of these account for gear use for all marine fisheries globally. We found that two industrial gear types, bottom trawling and purse seining, jointly account for over 53% of all catches, while bottom trawling alone dominated discarded catches. In the small-scale sector, over 60% of catches were caught by gillnets, various line gear, and encircling nets. Small-scale fisheries contributed most to the value of landed catches, while industrial bottom trawlers were responsible for discarding large amounts of potentially valuable catches. Catches by purse seines fluctuated over time, mainly due to variability of the underlying species, e.g., anchovies and sardines. The distribution and scale of use of different fishing gears, combined with knowledge of their divergent environmental impacts should allow a new wave of research into the global impacts of fisheries.

Efficiency of fishing gears in the river Halda, Chittagong, Bangladesh

To determine the catch efficiency of fishing gears, catch per unit effort (CPUE)data were collected for two years during January 2007 to December 2008 from the river Halda. Analyses were done to examine the variation of CPUE among gears, studied sections, months and years. The mean CPUE for pooled data of all gears was 2.247±0.265 kg.gear-1day-1 and 2.697±0.355 kg.gear-1day-1 for 2007 and 2008 respectively. Among eight gear categories, bag nets yielded the highest CPUE during 2007 (5.957±0.704 kg.gear-1day-1) and seine nets during 2008 (7.288±1.477 kg.gear-1day-1). Among 31 gear types, small meshed bag nets yielded the highest CPUE (18.065±6.660 and 15.69±4.479 kg.gear-1day-1 during 2007 and 2008 respectively). CPUE was highest during March-April and September-November periods. Analysis of variance showed significant difference among catch rates of different fishing gears. The CPUE differed significantly among different months for net fence, gill net, cast net and scoop net during 2007; and for seine net, net fence, bag net and cast net during 2008.

Efficiency of fishing gears in the river Halda, Chittagong, Bangladesh

To determine the catch efficiency of fishing gears, catch per unit effort (CPUE) data were collected for two years during January 2007 to December 2008 from the river Halda. Analyses were done to examine the variation of CPUE among gears, studied sections, months and years. The mean CPUE for pooled data of all gears was 2.247±0.265 kg.gear-1day-1 and 2.697±0.355 kg.gear-1day-1 for 2007 and 2008 respectively. Among eight gear categories, bag nets yielded the highest CPUE during 2007 (5.957±0.704 kg.gear-1day-1) and seine nets during 2008 (7.288±1.477 kg.gear-1day-1). Among 31 gear types, small meshed bag nets yielded the highest CPUE (18.065±6.660 and 15.69±4.479 kg.gear-1day-1 during 2007 and 2008 respectively). CPUE was highest during March-April and September-November periods. Analysis of variance showed significant difference among catch rates of different fishing gears. The CPUE differed significantly among different months for net fence, gill net, cast net and scoop net during 2007; and for seine net, net fence, bag net and cast net during 2008.

Impacts of fisheries bycatch on marine turtle populations worldwide: toward conservation and research priorities

Fisheries bycatch is considered the most serious threat globally to long‐lived marine megafauna (e.g., mammals, birds, turtles, elasmobranchs). However, bycatch assessments to date have not evaluated population‐level bycatch impacts across fishing gears. Here, we provide the first global, multi‐gear evaluation of population‐level fisheries bycatch impacts for marine turtles. To compare bycatch impacts of multiple gears within and among marine turtle populations (or regional management units, RMUs), we compiled more than 1,800 records from over 230 sources of reported marine turtle bycatch in longline, net, and trawl fisheries worldwide that were published between 1990–2011. The highest bycatch rates and levels of observed effort for each gear category occurred in the East Pacific, Northwest and Southwest Atlantic, and Mediterranean regions, which were also the regions of highest data availability. Overall, available data were dominated by longline records (nearly 60% of all records), and were non‐uniformly distributed, with significant data gaps around Africa, in the Indian Ocean, and Southeast Asia. We found that bycatch impact scores—which integrate information on bycatch rates, fishing effort, mortality rates, and body sizes (i.e., proxies for reproductive values) of turtles taken as bycatch—as well as mortality rates in particular, were significantly lower in longline fishing gear than in net and trawl fishing gears. Based on bycatch impact scores and RMU‐specific population metrics, we identified the RMUs most and least threatened by bycatch globally, and found wide variation among species, regions, and gears within these classifications. The lack of regional or species‐specific patterns in bycatch impacts across fishing gears suggests that gear types and RMUs in which bycatch has the highest impact depend on spatially‐explicit overlaps of fisheries (e.g., gear characteristics, fishing practices, target species), marine turtle populations (e.g., conservation status, aggregation areas), and underlying habitat features (e.g., oceanographic conditions). Our study provides a blueprint both for prioritizing limited conservation resources toward managing fishing gears and practices with the highest population impacts on sea turtles and for enhancing data collection and reporting efforts.

Can fishermen allocate their fishing effort in space and time on the basis of their catch rates? An example from Spermonde Archipelago, SW Sulawesi, Indonesia

Spatial and temporal patterns in catch rates and in allocation of fishing effort were analysed for the coastal fishery in Spermonde Archipelago, Indonesia, to assess whether fishermen can optimise their strategy from catch information, or whether they fish under great uncertainty and merely minimise risks. On average 517 fishing units operated in the 2800 km2area, catching 21 t fish day−1. Major gear categories were hook and line (59% of total effort and 5% of total catch), and lift nets (16% of total effort and 70% of total catch). The size of individual resource spaces varied with gear type and was smaller in unfavourable weather conditions. Although spatial patterns in catch rates at the scale of the whole archipelago were evident, fishermen could not differentiate between locations, as catch variance within their individual resource spaces was high relative to the contrasts in spatial patterns. The aggregated distribution of fishing effort in Spermonde must be explained by factors such as the small scale of operations, rather than fish abundance.