Gear Types Research Articles

Entropy-Aided Meshing-Order Modulation Analysis for Wind Turbine Planetary Gear Weak Fault Detection under Variable Rotational Speed.

As one of the most vital energy conversation systems, the safe operation of wind turbines is very important; however, weak fault and time-varying speed may challenge the conventional monitoring strategies. Thus, an entropy-aided meshing-order modulation method is proposed for detecting the optimal frequency band, which contains the weak fault-related information. Specifically, the variable rotational frequency trend is first identified and extracted based on the time-frequency representation of the raw signal by constructing a novel scaling-basis local reassigning chirplet transform (SLRCT). A new entropy-aided meshing-order modulation (EMOM) indicator is then constructed to locate the most sensitive modulation frequency area according to the extracted fine speed trend with the help of order tracking technique. Finally, the raw vibration signal is bandpass filtered via the corresponding optimal frequency band with the highest EMOM indicator. The order components resulting from the weak fault can be highlighted to accomplish weak fault detection. The effectiveness of the proposed EMOM analysis-based method has been tested using the experimental data of three different gear fault types of different fault levels from a planetary test rig.

Lower thermal tolerance restricts vertical distributions for juvenile albacore tuna (Thunnus alalunga) in the northern limit of their habitats

IntroductionEvaluating the thermal tolerance of commercially valuable tuna species and their behavioral responses to the limits of this tolerance is essential for evaluating the effects of changes in water temperature driven by global climate change on their distribution and fisheries. We aimed to identify the lower thermal tolerance (Tmin) of juvenile albacore tuna (ALB) and evaluate their behavioral response to Tmin by focusing on wild behavior in the northern distributional limit. Additionally, we investigated how vertical behavior is linked to the vulnerability of ALB to Japanese longline (LL) and pole-and-line (PL) fisheries.MethodsWe explored the swimming depths and water temperatures of four previously reported tagged individuals migrating from subtropical to temperate areas and identified Tmin and its depths in the water column as unfavorable depths (DTmin). To investigate the spatial patterns of ALB fishery grounds for LL and PL fisheries, we analyzed hotspots specific to each type of gear using the historical Japanese fishery logbook for both fisheries.ResultsComparisons of the fishery grounds between the two fisheries revealed that PL hotspots appeared in the northern areas, while LL hotspots were in the southern regions. We also discovered that the vertical distribution of ALB became shallow in high-latitude areas, which were strongly affected by DTmin shallowing at high latitudes.DiscussionThese results provide evidence of a behavioral response among juvenile ALB that avoids Tmin by remaining at the surface. We discuss the implications of the results for latitudinal changes in the vulnerability of ALB to fisheries in terms of the overlapping depth between ALB vertical habitats and the gear-setting depth for each fishery.

Fishing effort dynamics around the Galápagos Marine Reserve as depicted by AIS data.

The waters around the Galápagos Marine Reserve (GMR) are important fishing grounds for authorized artisanal vessels fishing within the reserve as well as for national and foreign industrial fleets operating in the wider Ecuadorian Insular Exclusive Economic Zone (IEEZ). Although it was not originally designed for fisheries management, Automatic Identification System (AIS) data provides useful, open access, near real-time and high-resolution information that allows for increased monitoring, particularly around Marine Protected Areas (MPAs) and in Areas Beyond National Jurisdiction. This study uses AIS data provided by Global Fishing Watch to assess the spatial distribution and seasonal dynamics of fishing effort by vessel flag within the GMR and the IEEZ from 2012 to 2021. Based on kernel density estimation analysis, we determinate the core-use areas (50%) and spatial extent (95%) of fishing activities by fleets (Ecuadorian and foreign), gear types and seasons (warm, from December to May; and cold, from June to November). Our results show that the Ecuadorian fleet recorded the most observed fishing hours in the study area, with 32,829 hours in the IEEZ and 20,816 hours within the GMR. The foreign flags with the most observed fishing hours in the IEEZ were Panama (3,245 hours) and Nicaragua (2,468.5 hours), while in the GMR were the 'Unknown flag' (4,991.4 hours) and Panama (133.7 hours). Vessels fished employing different fishing gears, but the waters of the GMR and IEEZ were mostly targeted by tuna purse-seiners and drifting longlines. The spatial distribution of the fishing effort exhibits marked seasonal variability, likely influenced by seasonal migrations of target species such as tunas (e.g., Thunnus albacares, T. obesus and Katsuwonus pelamis), marlins (e.g., Makaira nigricans) and sharks (e.g., Alopias pelagicus). The collection and use of this type of spatial and seasonal information is an essential step to understand the dynamics of fishing activities in national waters and improve fisheries management, particularly in less studied areas and fisheries.

Authority of Sarak Opat in Settlement of Environmental Pollution Cases

The existence of fishing gear type padang hoe began to spread in the area of Lake Lut Tawar, Central Aceh. As a result of massive and uncontrolled fishing practices and disregard for local culture, this is very dangerous for the preservation of Lake Lut Tawar. So if it continues to be left unchecked, fish endemic to Lake Lut Tawar, such as the depik fish, are threatened with extinction. In the Gayo community in Central Aceh District, cases/disputes that occur within the community are resolved by a customary institution called sarak opat. The purpose of this study is to find out the authority of sarak opat in solving environmental pollution and to find out the obstacles of sarak opat in solving environmental pollution. This type of research is empirical normative research. The data sources used are primary data and secondary data obtained from primary legal materials, secondary legal materials and tertiary legal materials. The method of collecting data is through interviews and document studies. The way of analyzing the data that has been collected from both primary and secondary data will be analyzed qualitatively, so that it is found that facts as symptoms of primary data are associated with theories from secondary data presented descriptively. The results of the study explained that sarak opat's authority has a legal basis for resolving environmental pollution cases, as mandated in the Aceh Qanun and the Aceh Governor's Regulations concerning Implementation. Customary and Indigenous Dispute/Dispute Resolution. custom. Obstacles to the sarak opat customary institution in resolving environmental pollution cases, namely: First, the loss of the function of the Pawang Lut in Gayo society. Second, there is a lack of understanding of the apparatus of the Sarak Opat customary institution regarding the authority to settle cases of minor environmental pollution.

Ghost Gears in the Gulf of Gabès: Alarming Situation and Sustainable Solution Perspectives

This study represents a first step in investigating the prevalence, causes, and spatial distribution of Abandoned, Lost, or Discarded Fishing Gears (ALDFGs) in the Gulf of Gabès, a critical fishing area in Tunisia. Five main fishing gear types—benthic trawls, encircling nets, longlines, gillnets, and trammel nets were analysed for their loss rates and contributing factors. The study involved extensive surveys among local fishermen and the use of geographic information system (GIS) tools for spatial mapping. The findings reveal varying loss rates among different gear types, with longlines experiencing the highest losses (59%), followed by trammel nets (45%), gillnets (40%), trawls (38%), and encircling nets (36%). Causes of gear loss include entanglement on obstructions, conflicts with other fishing gears, entanglement with marine animals, adverse weather conditions, and intentional dumping at sea. The study highlights the challenges posed by the consistent increase in fishing effort in the region. Spatial distribution mapping indicates two significant concentrations of ALDFGs, correlating with specific fishing activities and depths. The study emphasizes the importance of addressing gear losses as a threat to marine biodiversity and ecosystem health. Recommendations for mitigation include improving boat equipment, raising awareness among fishermen, implementing effective waste management, and exploring economic incentives for ALDFG recovery. This research contributes essential insights for fisheries management, environmental conservation, and sustainable practices in the Gulf of Gabès. Collaborative efforts are crucial for developing and implementing strategies that minimize the impact of ALDFGs on the marine environment while supporting the socio-economic interests of fishermen.

Another One Bites the Net: Assessing the Economic Impacts of Lagocephalus sceleratus on Small-Scale Fisheries in Greece

The assessment of the economic impacts of marine invasive species is fundamental for adopting mitigation measures, yet such impacts have been underreported in the Mediterranean Sea. The silver-cheeked toadfish (Lagocephalus sceleratus) is a toxic pufferfish that since its introduction has seriously disturbed small-scale fisheries along the eastern Mediterranean coast. This species depredates on fishing gears, causing damage to nets, longlines and commercial catches. To quantify its economic impact on small-scale fisheries, we interviewed 141 fishers from Crete (Cretan and Libyan Sea) and the Ionian Sea (Greece) during May 2020–December 2022. The mean annual economic cost resulting from L. sceleratus depredation was estimated at EUR 6315 ± 2620 per vessel in Crete and EUR 258 ± 120 in the Ionian Sea. Additionally, observer surveys carried out on board small-scale fishing vessels in Crete showed that depredation probability was significantly influenced by fishing depth, sea surface temperature, gear type (nets, longlines) and region (Cretan, Libyan Sea). L. sceleratus was caught more frequently and in higher numbers in the Libyan Sea. In response to depredation, fishers in Crete have altered their fishing tactics in terms of fishing in deeper waters, reducing fishing time and changing the technical characteristics of fishing gears. Our results underscore the adverse impacts of L. sceleratus on Greek small-scale fishers, emphasizing the need for region-specific management plans where the species establishes large populations.

Fishing Crafts and Gears Operated in Junput Mangrove, Purba Medinipur for Sustaining the Livelihood of Local Fishermen

Fishing practices are an old-age activity that has been carried out since time immemorial. Different primitive, low-cost, non-mechanized and motorized crafts and gears operated in different parts of the country. In our state of West Bengal, vast ranges of crafts and gears have been used to catch fish in different water bodies. Fishermen of our state evolved various fishing devices that enhance fish production and uplift local and national economies. Though emphasizing the above view, the present study was aimed to document different customary and mechanized fishing crafts and gears used in Junput coast, Purba Medinipur. Junput is a seaside resort city in the state of West Bengal, India. It lies at the northern end of the Bay of Bengal. It is the most popular sea resort in West Bengal, renowned for its beaches. In the Junput mangrove area, few canals were well connected with the Bay of Bengal. Thus, the diversity of ichthyofauna and shellfish was abundant. For harvesting them, local fishermen use different types of crafts and gears, which have been documented during the study period. Available crafts were Bamboo raft, Plank built boat (commonly known “Nauka”), Wooden framed boat (commonly known “Nauka or Dingi”), Thermocol raft, Rubber tube boat. Available gears used for capturing fishes were Gill net (commonly known as "Bindha jal, Phansa jal, Phanda jal”), Cast net (commonly known “Phenka jal, Khei jal”), Drag net (commonly known “Maha jal”), Scoop net without handle (commonly known “Chakni jal, Chha jal”), Hook and line (commonly known “Bardsi”), Trap.

Meshing equation, tooth contact analysis, stress analysis and manufacture of a point-contact gear formed by double-arc milling cutter

The processing and design of point-contact gears have attracted the interest of many scholars. The point-contact gears are usually processed by specialized machines (face-milling and face-hobbing) or five-axes machines (forming milling). In this paper, a new type of point-contact gear formed by double-arc milling cutter on four-axes machine is proposed. Firstly, the meshing equation is proposed to obtain a pair of processing traces that satisfy the law of gearing, and the processing traces are also contact traces. Considering the important role of traces in obtaining the proposed gear, this gear is called as TG. Then, six pairs of contact traces for parallel-axes, crossing-axes, and skewing-axes TGs are solved. Furthermore, the tooth surface models are studied and the obtained models are used for tooth contact analysis and stress analysis, and then the instantaneous contact areas, the contact stresses, and transmission errors are obtained, respectively. Lastly, the TG pair with cross-axes is processed, and then, the measurement and rolling experiments are conducted. The obtained results indicate the meshing equation, tooth surface models, and milling method are feasible. The proposed milling method provides a new way for flexible and diversified manufacturing of point-contact gears.

Predicting important fishing grounds for the small-scale fishery, based on Automatic Identification System records, catches, and environmental data

Abstract Effective and sustainable management of small-scale fisheries (SSF) is challenging. We describe a novel approach to identify important fishing grounds for SSF, by implementing a habitat modelling approach, using environmental predictors and Automatic Identification System (AIS)-B data coupled with logbook and First Sales Notes data, within the SE Bay of Biscay. Fishing activity patterns and catches of longliners and netters are used to determine the main environmental characteristics of the fishing grounds, and a habitat modelling approach is implemented to predict the zones that fulfil similar environmental characteristics across a larger geographical extent. Generalized additive mixed models (GAMMs) were built for 24 fish species, and to identify other zones that fulfil similar characteristics and, thus, could be considered relevant for the species targeted by each gear type. Most of the models showed a good prediction capacity. The models included between one and four predictor variables. ‘Depth of mixing layer’ and ‘benthic rocky habitat’ were the variables included more frequently for fish species captured by netter’s fleet. For longliners, the ‘seafloor slope’ and ‘benthic rocky habitat’ were the two most important variables. The predictive maps provide relevant information to assist in management and marine spatial planning.

A Modified Approach to the Rack Generation of Beveloid Gears

The purpose of this paper is to present an easier and more efficient method for the determination of the geometry of a bevelled gear tooth. Based on a method that provides an easier way for the rack generation of involute helical gears, the mathematical model of a beveloid gear is studied. The mathematical procedure for developing two-dimensional cross-sections has been extended to three-dimensional gear models. A computer programme is developed to obtain generating and generated surfaces. The proposed algorithm is compared with the previous studies for verification and validation. The results demonstrate that the coordinates obtained from the given method are nearly the same on the start and end points of the main gear parts, such as the involute and root fillets regions. Also, between the limits, the values can be considered acceptable. A coordinate deviation of the gear profile has been observed in the mathematical model, because of the profile shift. Modifications have been developed in the equations to eliminate these cases. The main advantage of the proposed method is to obtain mathematical models without carrying out some of the calculation steps used in previous studies. Eventually, this feature will provide an easier and faster method to develop computer-aided models of the beveloid gear types.

The spatio-temporal distribution of small-scale fisheries along the northern Panay Gulf, Philippines: Implications for management

The small-scale fisheries along the northern region of the Panay Gulf face a distinctive challenge as multiple communities compete for access to the same fishing areas and resources. In response, neighboring coastal municipalities implemented conventional management measures, such as Marine Protected Areas (MPAs) and seasonal closures, aiming to enhance the abundance of fisheries resources. However, these measures only imposed economic hardships on artisanal fishermen. To address this issue, a survey involving 135 informants from coastal barangays was conducted between June to November 2021. The study used semi-structured questionnaires and GPS data loggers to collect essential information on the spatial and temporal distribution of fishing activities and specific target catches. The integration of local knowledge played a crucial role in bridging critical data gaps within the study site, facilitating the identification of more effective management reforms. The findings revealed that traditional harvest locations for various gear types exhibited zonation patterns across the gulf. Fishing activities were strategically conducted in areas with available resources, often disregarding municipal fishing boundaries. Coordinated management strategies are deemed imperative due to the varying timing of seasonal closures among municipalities. On the other hand, the temporal analysis of fishing activities revealed peak seasons of fisheries resources, providing a basis for adjusting the selection of target species and the duration of seasonal closures. Interestingly, the existing management measures failed to reduce the annual fishing activities and were ineffective, contrary to popular claims. This outcome was primarily due to constant shifts in the types of fishing gear used and target catches between seasons, highlighting the displacement of exploitation. In conclusion, this study underscores the importance of aligning fisheries policies with the dynamic nature of small-scale fisheries. Unless these policies adapt to the evolving conditions of the sector, they are likely to remain ineffective in addressing issues faced by artisanal fishermen in the region.

Stable isotopes reveal intertidal fish and crabs use bivalve farms as foraging habitat in Puget Sound, Washington

Bivalves such as oysters and clams have been farmed in intertidal zones across the Puget Sound region of the Salish Sea for thousands of years. The variety of gear types used on bivalve farms creates complex vertical structure and attachment points for aquatic epiphytes and invertebrates which increases habitat structural complexity, but may alter eelgrass cover in areas where bivalve farms and eelgrass meadows overlap. Eelgrass meadows are highly productive and ecologically foundational nearshore habitats that provide valuable ecosystem services including the provision of nursery, refuge, and foraging habitat. Aquaculture has been a key feature of the environment in the Puget Sound for millennia, however, little is known about how well aquaculture practices are integrated into the system, and what services they provide to mobile species assemblages relative to unfarmed eelgrass meadows. We used stable isotope mixing models to estimate, for several species of nearshore fish and crab in two areas of North Puget Sound, Washington, the percent diet originating from either a natural bottom habitat (eelgrass meadows), farm habitat (oyster farms), or pelagic planktonic sources. Our results indicate that several species of nearshore fish such as surf perch and staghorn sculpin derive a significant proportion of their diets from farm areas, while crabs derive most of their diets from eelgrass habitat, and stickleback derive a significant proportion of their diets from planktonic sources. The results indicate that foraging habitat uses are species specific, and that several species that spatially overlap bivalve farms obtained a large percentage of their diets from adjacent bivalve farm habitat.

A database of mapped global fishing activity 1950–2017

A new database on historical country-level fishing fleet capacity and effort is described, derived from a range of publicly available sources that were harmonized, converted to fishing effort, and mapped to 30-min spatial cells. The resulting data is comparable with widely used but more temporally-limited satellite-sourced Automatic Identification System (AIS) datasets for large vessels, while also documenting important smaller fleets and artisanal segments. It ranges from 1950 to 2017, and includes information on number of vessels, engine power, gross tonnage, and nominal effort, categorized by vessel length, gear type and targeted functional groups. The data can be aggregated to Large Marine Ecosystem, region and/or fishing country scales and provides a temporally and spatially explicit source for fishing effort and fleet capacity for studies aimed at understanding the implications of long-term changes in fishing activity in the global ocean.

VIRTUAL AND AUGMENTED REALITY TECHNOLOGIES IN THE FINE ARTS OF THE FIRST HALF OF THE XXI-ST CENTURY: HISTORIOGRAPHICAL REVIEW

The article analyzes the history of VR/AR research in the field of art and design throughout 21st century scientific publications. Use of virtual spaces for the presentation of artworks and enhancement of visitor engagement is not a new addition to cultural space and was experimented with by multiple people, including the author of this article himself. VR is also increasingly often, albeit, still being more of an experimental novelty, used as a tool for teaching and/or learning art and history, sometimes — technical disciplines like engineering or physics. Solely art-focused research, however, is quite lacking in numbers, in part because there aren’t many examples of the use of VR/AR in art and design projects, at least so far, yet there have been a number of different experiments ranging from psychology-adjacent to ones being on the line between art and IT. For the purpose of this article, questions of distinction between “true VR” (fully 3D interactive world experienced through VR gear), virtual environments that do not need VR gear and various types of artificial and mixed reality and differences of between them, especially when it comes to artistic use, will likely be left out for separate discussion. We are more interested in how the art world used, iterated upon and ultimately accepted the freedom and new forms of expression allowed by virtual, augmented and mixed reality technologies. As most notable and expressive works and more importantly scientific research of these works have appeared in the 21st century, we will limit our overview of art-specific papers to this time period. Papers reviewed in this article are divided into four different categories, each with its own general research goal that most of the articles inside the same group share between themselves: virtual museums or galleries and preservation of cultural heritage, artworks and immersive typography, education, behavioral research on the basis of viewer-artwork interactions. With first three categories being well understood, when it comes to the usefulness of research results and experiments themselves, fourth one is exceptionally useful as relatively easy and universal way to “predict” viewer behavior in different circumstances for both gallery owners and artists (gallery layouts, lighting, artwork composition, color contrast between artworks, etc).

Effects of Profile Shifting of a Cosine Gear

Cosine gears are a special type of gear drive, in which the tooth profile of the theoretical generating rack is described by the cosine function. According to recent research results, the cosine gear drive has a lower slip coefficient and the contact and bending stresses supported by the teeth during the load are smaller than those occurring in involute gears. The main advantage of the cosine drive pair lies in the apparent higher rigidity of the gear tooth: this can reduce flank wear and increase gear life, especially in heavy load and highspeed applications. In contrast to involute profile gears, cosine gears do not show undercut root fillet, even with small teeth number. This paper deals with cosine gear tooth profile design and the meshing of the cylindrical cosine gear pair conceived without, or with the application of the profile shifting. The mathematical model of the meshing was implemented in a Mathcad environment, showing that there exists a significant difference compared to the well-known involute gears. The simulation of the motion during the rolling of the gear pairs was realized with the Autolisp programming interface. Solid models were created and tested in the Autodesk Inventor environment.

Multi-Use as the Next Iteration of Ecosystem-Based Management Planning and Implementation

In the not-so-distant future, it may be entirely possible for an aquaculture farmer to harvest robust crops of seaweeds and shellfish safely within the leased area of an offshore wind farm. Likewise, a charter boat captain may tap into turbine sensors for weather and traffic data needed to navigate a boatload of recreational anglers to productive fishing grounds. Or, perhaps, commercial fishermen deploy innovative gear types on modified vessels to safely and lucratively fish within wind farms.

A review and synthesis of the benefits, drawbacks, and considerations of using traps to survey fish and decapods

Abstract Traps (or pots) are one of the oldest and most widespread scientific survey gears for fish and decapod crustaceans around the world. Here, I review and synthesize the extensive scientific literature describing the various benefits and drawbacks of using traps as a survey gear in scientific studies. The widespread use of traps in fish and decapod surveys is due to several characteristics like their low cost, flexible design, ease of use, ability to fish unattended, and being amenable to pairing with other gears. However, there are a number of significant drawbacks of using traps, including highly variable catches due to environmental fluctuations or behavioral interactions or lost traps that continue catching and killing animals, that must be considered and accounted for when initiating trap surveys. This study highlights the types of habitats and species most and least suited for monitoring by traps, and emphasizes the importance of matching the goals and objectives of a trap survey with the correct trap design, mouth entrance, bait type, soak time, and pairing of gears. Pilot studies are also recommended before surveys are initiated to quantify the selectivity patterns of traps and identify the various factors that may influence trap catch.

Static transmission error measurement of various gear-shaft systems by finite element analysis

Transmission error (TE) is a significant parameter related to gears vibration widely investigated by many authors using different approaches. However, in previous studies, spur and helical gears were mainly examined. There is a lack of studies addressed to double helical and herringbone gears and a comparison among several types of gearing with parallel axes. In this paper, spur, helical, double helical, and herringbone gears are analyzed in terms of static transmission error (STE), contact pressure and tooth root stress. Static contact analyses were conducted using the finite element method (FEM) which is often considered a tool for validating other methods and approaches. Moreover, three variants of boundary conditions of each gear type are introduced, including flexible shafts and the effect of a tip relief modification at sole gears, without shafts, was analyzed. In addition, a concept of a compact test rig intended for STE measurements at low loads was presented. The results have shown, among other things, significant influence of the shaft stiffness and boundary conditions on meshing characteristics.

Evaluation of Illegal, Unreported and Unregulated (IUU) Trawl Infringements Committed by Turkish Fishing Vessels

This study analyses a highly damaging and prevalent fishing practice of trawl infringements, which is one of the crucial components of IUU fishing in Turkish waters. The raw data gathered from the Turkish Coast Guard Command (TURCG), covered 2012 – 2014 period. Data covered a total of 1040 trawl infringements, with considerable differences in trawling violations among the seas surrounding Türkiye; the Black Sea, the Sea of Marmara, the Aegean Sea, and the Mediterranean Sea. With respect to trawling infringements, the Sea of Marmara (37%) and Istanbul Strait (15%) were the hot points. The most common infringement type was trawling in a closed area (43%) and when combined with the rate of infringements on trawling during the closed season (10%), these violations accounted for 53% of spatio-temporal infringements. Regarding illegal trawling by vessel type, trawl vessels had a 44% share and non-trawlers had a share of 56%, of which included infringements by other type of fishing vessels (46%) and non-fishing vessels (10%). It was also found that infringement by vessels smaller than 12 meters in length had a share of 46%. These vessels (known as "şebeke" in Turkish), trawl illegally using small types of nets and gears in coastal waters without giving any obvious indication of fishing activity. The results of this study will be useful to policy-makers, practitioners and scientists to successfully combat trawling infringements by providing information on distribution, intensity and methods of trawl violations.

Evidence for a male bias in Atlantic blue crab pot‐based sampling

AbstractObjectiveThe Atlantic blue crab Callinectes sapidus (hereafter, “blue crab”) is an ecologically and economically important species that supports one of the highest valued commercial fisheries in coastal South Carolina, USA. Researchers at the South Carolina Department of Natural Resources conduct multiple surveys to monitor the status of the blue crab by using a variety of gear configurations. Demographic characterizations can often be influenced by sampling gear‐related biases.MethodsWe compared blue crab sex ratios between passive, pot‐based sampling and active, trawl‐based sampling in the fall across three estuaries and for year‐round sampling in a single estuary (Ashley River, South Carolina).ResultDuring the fall, there was a difference of 20.1% between the percentage of males collected in pot‐based sampling (73.5%) and the percentage of males in trawl‐based sampling (53.4%). Furthermore, an overall male bias of 23.0% was observed for year‐round sampling in the Ashley River; however, this bias was only significant in certain months.ConclusionOur findings suggest that although particular sampling gears may have specific advantages, such as greater suitability to effectively sample certain habitats, the resulting characterizations of blue crab population demographics can differ among gear types. Recognizing gear‐related biases is important for ensuring that field surveys are representative of population demographics, particularly when sex‐specific modeling approaches are used as part of stock assessments to determine population status.