Fish Attraction Research Articles

Swimming performance of adults and copepodites of Caligus rogercresseyi against different water flow speeds in presence or absence of light and host fish attractants

Swimming performance of adults and copepodites of Caligus rogercresseyi against different water flow speeds in presence or absence of light and host fish attractants

Attraction and avoidance of wild demersal fish and crustaceans to open-net aquaculture pens resolved by baited and towed underwater camera surveys

Attraction and avoidance of wild demersal fish and crustaceans to open-net aquaculture pens resolved by baited and towed underwater camera surveys

PENGARUH FASE BULAN TERHADAP HASIL TANGKAPAN IKAN DI PELABUHAN MUNCAR KABUPATEN BANYUWANGI

The influence of the moon's phases in the sky is a factor that is closely related to the behavior of fish, one of which is the fish's attraction to light. The purpose of this research was to examine the differences in fish catches based on the phases of the moon at Muncar Port, Banyuwangi Regency. This type of research is descriptive quantitative research with ex post facto survey method. This research uses ex post facto research with a Causal Comparative Research design. The results showed that there was no difference in fish catch based on the phase of the moon in one year. The results of the analysis that has been carried out show that the average fish catch in each phase of the moon in one year is almost the same. Based on the research data, it can be concluded that in the bright moon, the fish catches are less. However, during the dark moon the fish catch becomes abundant.

A Eulerian-Lagrangian model for simulating fish pathline distributions in vertical slot fishways

Recovery of the river connectivity relies on the application of structural and non-structural solutions. Within the structural solutions, vertical slot fishways (VSF) are most popular, but achieving the desired efficiency remains a challenge. To this end, evaluation of both biological and hydraulic efficiency is imperative. A Eulerian Lagrangian Agent Based Model (ELAM) of fish upstream migration through VSFs is presented in this work that considers one passive and three active behaviors affecting fish swimming pathlines of bighead carps (Hypophthalmichthys nobilis) and silver carps (Hypophthalmichthys molitrix). The passive behavior consists in a 2-D random walk where no external stimuli are detected. The first active behavior represents fish attraction to a nearby flow region as a Gaussian distribution function of turbulent kinetic energy, velocity magnitude and velocity strain rate. The second active behavior represents wall collision avoidance, whereas the third considers the tendency of the fish to escape from high velocity zones. Stochasticity is considered in the model to represent the dispersion in the experimental pathlines. The ELAM is tested for two different VSF configurations and is found to well reproduce the experimental pathlines, particularly when the escaping response to high velocity zones is considered. Results show that the ELAM model can be used as an appropriate tool for modelers and designers to evaluate fish passage efficiency.

Identification of key habitats and conservation threats of the Ganges River dolphin (Platanista gangetica) of Bangladesh

Ganges River Dolphins (Platanista gangetica) are known to inhabit all major river systems in Bangladesh. However, comprehensive spatial records for this globally endangered aquatic mammal are notably scarce nationwide. Furthermore, their habitats are increasingly threatened due to excessive utilization of aquatic resources and their habitats by the growing human population. To allocate limited resources in safeguarding high-priority dolphin habitats, we conducted field surveys and arranged stakeholder consultations to identify key dolphin habitats and the conservation threats they face across Bangladesh. Through this process, we have identified 14 river segments as high-priority winter habitats for Ganges River Dolphins. These dolphins encounter both direct and indirect threats within their habitats. Direct threats include entanglement and occasional intentional killing for traditional medicinal purposes and as fish attractants. Indirect threats leading to habitat degradation comprise the construction of dams and barrages for upstream water extraction, increasing industrial pollution in river waters, overfishing, and alterations to river morphology caused by siltation and sedimentation. The heavy reliance of local communities on dolphin habitats, coupled with a lack of widespread awareness and insufficient conservation efforts, pose significant challenges to the future survival of Ganges River Dolphins in Bangladesh. Bangladesh J. Zool. 51(3): 253-266, 2023

Unmanned surface vehicle (USV) with a fish attraction lamp to assist the purse seine operations

Unmanned surface vehicle (USV) with a fish attraction lamp to assist the purse seine operations

Flow hydrodynamics drive effective fish attraction behaviour into slotted fishway entrances

Flow hydrodynamics drive effective fish attraction behaviour into slotted fishway entrances

Restoration of a fish-attracting flow field downstream of a dam based on the swimming ability of endemic fishes: A case study in the upper Yangtze River basin

The construction of fish passage facilities can mitigate the negative effects of dams and other water engineering construction on river connectivity and have a significant positive effect on the conservation of local fish diversity. To attract target fishes into fish passage facilities effectively, the optimal flow velocity range to attract fish must be determined. Three local endemic species of the Mishi Reservoir were considered as the protection targets. However, their swimming abilities remain unclear. Therefore, the induced swimming speed (Uind), critical swimming speed (Ucrit) and burst swimming speed (Uburst) of three fish species were tested. Based on these results, we identified the optimal flow velocity to attract fish, which falls within the range of 0.15–0.51 m/s. A validated three-dimensional hydrodynamic model was used to simulate different schemes. By comparing the flow field simulation results of different schemes, we obtained the optimal measure to restore the flow field, namely, a multiple engineering measure combining increased the fish attraction flow in the fish collection pond and the construction of a spur dike. This study offers a solution for the specific case and enhances the database of swimming characteristics of endemic fish in the upstream reaches of the Yangtze River. It also provides a valuable reference for designing fish-attracting flows and potential measures for restoring flow fields in similar future projects.

Olfactory cueing responses in the early stages of a marine estuarine-dependent fish species in South Africa

Many marine fish species depend on estuaries as nurseries for their vulnerable life stages. Consequently, successful recruitment into estuaries by the larvae and juveniles of marine estuarine-dependant fish such as Rhabdosargus holubi (Sparidae) is vital to completing their lifecycles and thus maintaining populations. This species is known to be attracted to the water of riverine and estuarine origin, potentially via olfaction of chemical cues. However, the specific cues and cueing mechanisms involved in these recruitment responses have yet to be fully elucidated for many species utilising estuaries as nursery areas. In this study, choice chamber flume experiments were used to test the chemical attraction of fish to water from different sources to understand further the mechanisms and cues involved. Rhabdosargus holubi juveniles were attracted to the water of riverine and estuarine origin, as the larvae were previously shown to do. These fish were also attracted to exudates from seagrass that occur naturally in their preferred estuarine habitats. The results of the study highlight both the importance of conserving vegetated habitats and managing adequate freshwater flow into estuaries, as well as the need for more research on fish cueing into nursery areas.

Baseline Assessment of Ecological Quality Index (EQI) of the Marine Coastal Habitats of Tonga Archipelago: Application for Management of Remote Regions in the Pacific

The loss of coral habitats and associated biodiversity have direct effects both on the physical dynamics of the coast and on natural resources, threatening the survival of local populations. Conservative actions, such as the creation of new Marine Protected Areas, are urgent measures needed to face climate change. Managers need fast and simple methods to evaluate marine habitats for planning conservation areas. Here, we present the application of an Ecological Quality Index (EQI), developed for regional-scale habitat maps of the Atlas of the Marine Coastal Habitats of the Kingdom of Tonga, by processing Copernicus Sentinel-2 imagery. Both the habitat mapping classification and the EQI application were focused on the importance of coral reef, seagrass and mangrove habitats, both as natural defense and sustenance for the local populations. Twelve main Pacific reef habitats were evaluated through a three-level EQI score assigned to six parameters: nursery ground, connectivity, species reservoir, fish attraction, biodiversity and primary production. The EQI was integrated into a developed georeferenced database associated to the QGIS software providing the ability to identify on the maps the area of interest and the associated habitats, and to quantify their ecological relevance. The EQI is proposed as a tool that can offer to stakeholders and environmental managers a simple and direct indicator of the value of the marine coastal environment. The index may be handled for management purposes of vast areas with remote and uninhabited islands.

Acoustic telemetry system as a novel approach for evaluating the effective attraction of fish to artificial reefs

Due to there being a lack of suitable approaches for evaluating the effectiveness of artificial reefs, two experiments were designed to examine the feasibility of acoustic telemetry, a rapidly developing method for tracking aquatic animals. The first experiment was conducted to understand the deployment procedures of an acoustic telemetry system and determine the appropriate deployment of receivers’ spacing, while the second experiment was conducted to quantify the site fidelity and habitat use of 11 reef fish in the Fangchenggang artificial reef area in the northern South China Sea, China. The results indicated that the logistic regression model was an effective way to balance the detection probability at different distances between the range test transmitter and receiver, with above 50% detection probability within 240 m and 80% detection probability within 110 m. The residency index, as a quantification of site fidelity, was 0.85 ± 0.24. The 100% minimum convex polygon, 95% kernel utilization distribution, and 50% kernel utilization distribution, which are the indicators of habitat use, were 34,522.94 ± 35,548.95, 1,467.52 ± 1,619.05, and 236.01 ± 294.59 m2, respectively. High site fidelity and the small spatial scale of habitat use for reef fish demonstrated that artificial reefs were an effective man-made structure to attract fish. Overall, this study supports the feasibility of the acoustic telemetry system, indicating that it provides a good approach for quantifying the associations between artificial reefs and fish.

The effect of artificial reef design on the attraction of herbivorous fish and on coral recruitment, survival and growth

Fish assemblages of different types of artificial reefs can differ greatly in abundance, biomass and composition, with some reef types harboring over five times more herbivores than others. It is assumed that higher herbivorous fish abundance results in a higher grazing intensity, affecting the benthic community by means of enhanced coral recruitment, survival and growth. Territorial fish species might affect this process by chasing away other fish, especially herbivores. In this study we compared the fish assemblage, territorial behavior and grazing intensity by fish on two artificial reef types: reef balls and layered cakes, differing greatly in their fish assemblage during early colonization. In addition, the effect of artificial reef type on benthic development and coral recruitment, survival and growth, was investigated. Although layered cakes initially harbored higher herbivorous fish biomass, this effect was lost during consecutive monitoring events. This seems to be the result of the higher territorial fish abundance around the layered cakes where almost four times more chasing behavior was recorded compared to the reef balls. This resulted in a more than five times lower fish grazing intensity compared to the reef-ball plots. Although macroalgae were effectively controlled at both reefs, the grazing intensity did not differ enough to cause large enough structural changes in benthic cover for higher coral recruitment, survival or growth. The high turf algae cover, combined with increasing crustose coralline algae and sponge cover likely explained reduced coral development. We recommend further research on how to achieve higher grazing rates for improved coral development on artificial reefs, for example by facilitating invertebrate herbivores.

ОБ ОЦЕНКЕ КАЧЕСТВА УСЛОВИЙ ДЛЯ ПРИВЛЕЧЕНИЯ РЫБ В ПРИГИДРОУЗЛОВЫЕ РЫБОХОДНЫЕ И РЫБОХОДНО-НЕРЕСТОВЫЕ КАНАЛЫ

Purpose: to develop a methodology for predicting the quality of design solutions for waterworks fish passages and fish passages and spawning channels for the formation of conditions for attracting fish migrating for spawning into their channels. Materials and methods. The development was based on the results of experimental studies carried out on a hydraulic model of the spillway using small (“model”) fish. When setting up the experiment, the proven methods were used, and when processing experimental data, methods of mathematical statistics were used. Results and discussion. The data of experimental studies of the model fish approach to the entrance sections of fish passages under various hydrometric conditions in the zones of their movement and the size of the spillway have been obtained. The hydrometric factors that influence the attraction of fish from the waterworks downstream to the operation zone of the flow that attracts them and to the entrance to the fish pass are determined: flow rates and average flow velocity in the river and channel, width of the channel and river, attracting and cruising swimming speeds of fish, remoteness of the entrance (for fish) range of the channel from the upper boundary of the fish search area and its length. The qualitative characteristics of the influence of these factors on fish entry and the quantitative values of the degree of their influence on the attraction of fish to the entrances to fish passages have been established. Dependences were obtained. The dependences were tested in the calculation of the fish protection complex of the Bagaevsky waterworks, the efficiency of which (at a spillway discharge of 250 m³/s) is predicted at the level of 92.6 % of the number of fish approaching it. Conclusion. A mathematical model is proposed to determine the value of the quality index of hydrometric conditions in the downstream of the hydroelectric complex to attract fish to the entrance to the fish passage channel, which is a criterion for the quality of its design solution.

Strategic management of local potential-based entrepreneurship through community empowerment on fish attractions Bendhung Lepen in Mrican Village Yogyakarta

This research was aimed (1) to know the internal environmental factors that affect the management of entrepreneurship strategies for fish tourism attraction Bendhung Lepen; (2) to know external environmental factors that affect the management of entrepreneurship strategies for fish tourism attraction Bendhung Lepen; and (3) to know the appropriate marketing system for the location of Bendhung Lepen fish attractions. The method used in this study was qualitative descriptive where data were obtained by means of interviews, observations, and documentation. The interview was conducted at random on visitors to fish attraction Bendhung Lepen, the community around the Gajah Wong river irrigation site, and the Bendhung Lepen Community. Field results were used for SWOT analysis consisting of IFAS tables, EFAS tables, IE matrices, and SWOT matrices. The results of the analysis on IFAS can be known that the score for internal factors of 3.43 which understands the internal condition of management of fish attraction management in Bendhung Lepen falls into the moderate category (average). This is because factors that have a high score were at high operational cost points. The results of the EFAS analysis showed a score of 3.28 which means the external condition of Bendhung Lepen fish attractions were in good condition, where the most dominant factor is the number of competitors was still small, balanced crop sales, and the density of the number of tourist attraction visitors.

Identifying Hydraulic Characteristics Related to Fishery Activities Using Numerical Analysis and an Automatic Identification System of a Fishing Vessel

Many countries worldwide promote artificial reef projects to increase and preserve fishery resources; however, how artificial reefs form fisheries is unclear. Nevertheless, specific hydraulic features of artificial reefs may attract fish. We selected an underwater reef as a research site to clarify this hypothesis. In this study, environmental conditions around the underwater reef were modeled and quantitatively assessed using numerical analysis. We identified two hydraulic features related to fish attraction: the wake region and the local upwelling region. Their spatial distributions were superimposed on the path of a fishing vessel that was monitored using an automatic identification system (AIS). We showed that various hydraulic characteristics (such as wake region, local upwelling region, and flow velocity) identified in the path of the fishing vessel can be quantitatively evaluated. Increasing amounts of information from the AIS can be used to identify the hydraulic features that attract the most fish and therefore improve the productivities of artificial reefs.

Influence of fish attractant on hooking location of Lutjanus carponotatus and Epinephelus quoyanus caught with soft plastic and hard‐bodied lures

AbstractRecreational fishing gear continues to evolve, and factors such as anatomical hooking location may change over time due to technology creep. We revisited studies conducted in 1996 by re‐examining hooking location in experiments where hard‐bodied and soft plastic lures were presented to stripey (Lutjanus carponotatus) and wire netting cod (Epinephelus quoyanus) either with or without application of a synthetic fish attractant. These data were compared to those of fish hooked on organic bait using circle or J‐style hooks. Lure type and application of attractant both significantly affected hooking location. Addition of attractant to hard‐bodied lures reduced foul hooking of both species. For L. carponotatus, soft plastic lures both with and without attractant tended to be taken deeper than hard‐bodied lures. For E. quoyanus captured on soft plastic lures coated with attractant, hooking locations were similar to those using organic baits on circle hooks. However, deepest hooking of both species occurred using organic bait on J‐style hooks. The use of soft plastic lures with an effective fish attractant may result in deeper hooking, which could potentially influence post‐release survival and increase fishing power.

In situ observations of fish attraction to light-emitting diodes on an undersea observation deck

Many fisheries employ fishing lights to manipulate the behaviors of target fish and to attract them toward the light; however, relatively few long-time observations of fish attraction have been performed in the field. Here, an underwater observation deck was used to examine the differences in the fish-attracting effect of light-emitting diode (LED) lights on the number of attracted fish and on their behavior in the field, using white-edged rockfish as the target species. A total of 604 ± 324, 307 ± 203 and 171 ± 106 white-edged rockfish individuals were attracted to the observation window when it was illuminated with blue, green, and red light, respectively. Under the blue light, fish remained for 133.6 ± 129.8 s around the window, while under the for green and red light, they stayed for 72.5 ± 76.7 s and 45.7 ± 52.2 s, respectively. The longer time spent under the blue light may have result in an increase in the number of fish counted, and this would be related both to the transparency of this wavelength underwater and to the visual sensitivity of white-edged rockfish. Other light environments produced by the blue LED may have been suitable for this species, both in terms of preferred light intensity and optimal feeding environment. The results presented in this study contribute to a better understanding of the ecology of white-edged rockfish and suggest a selective and efficient use of this species in fisheries.

Attraction, Entrance, and Passage Efficiency of Arctic Grayling, Trout, and Suckers at Denil Fishways in the Big Hole River Basin, Montana

AbstractThe Big Hole River basin in southwestern Montana supports the only indigenous, self‐sustaining fluvial population of Arctic Grayling Thymallus arcticus in the conterminous United States, but the basin is fragmented by numerous low‐head irrigation diversion dams. Denil fishways at 63 diversion dams provide Arctic Grayling and other fishes opportunities for year‐round access to critical habitats; however, their efficiency has not been evaluated. We quantified attraction, entrance, and passage for hatchery‐reared Arctic Grayling, wild trout (Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta), and wild suckers (White Sucker Catostomus commersonii and Longnose Sucker C. catostomus) during 14 field trials conducted at six Denil fishways over a representative range of fishway slopes and hydraulic conditions using passive integrated transponder telemetry. Attraction (60.4–84.3%) and entrance (44.3–78.6%) efficiencies were variable across test conditions and reduced overall fishway efficiencies (19.1–55.8%). In contrast, upon entry, passage efficiencies were high (96.2–97.0%) for all taxa across all test conditions. Attraction of hatchery‐reared Arctic Grayling increased with upstream depth (a surrogate for fishway discharge) and attraction flow, but attraction of wild fish was less affected by these conditions. Entrance of Arctic Grayling, Brook Trout, and Brown Trout decreased with upstream depth and fishway slope, especially when plunging entrance conditions associated with shallow downstream depths were present. However, entrance of Arctic Grayling and both trout species increased with downstream depth, and submerged fishway entrances demonstrated promise for increasing entrance efficiency at fishways with high discharges and steep slopes. We demonstrate that comprehensive evaluations of fishway efficiency components can identify specific solutions that improve fishway efficiency; application of these engineering solutions at individual fishways (as needed) could improve their efficiency and further enhance aquatic connectivity for fishes in the Big Hole River basin and elsewhere.

Laboratory Studies on the Rheotaxis of Fish under Different Attraction Flow Conditions.

The damming of the river changes the structure of the original river ecosystem, and although fish passage plays an important role in maintaining the connectivity of the river ecosystem, the fish have difficulty finding the fish passage entrance during the upstream process. This paper studied the rheotaxis of fish under three different water flow conditions experimentally through recirculating water tanks. To better understand the response of Crucian carp (Carassius auratus) to water flow stimulation, the representative swimming trajectory, sensing success rate, attraction success rate, reaction time, and attraction time of the fish were analyzed by using a video monitoring system. The experimental results showed that fish responded differently to single-peak and lateral bimodal outflow conditions: (1) the single-peak outflow condition had a much better attraction effect than the lateral bimodal outflow condition, both in terms of sensing success rate and attraction success rate; (2) the fish swam mainly in the middle area of the lateral bimodal outflow condition, while the fish swam more evenly in the single-peak outflow condition. Therefore, setting the attraction current at the right time and near the entrance of the fish passage may help to improve the effect of fish attraction.

Koi Fish Pattern As A Source Of Inspiration In Painting

The general purpose of this research and creation is to revive the author's love for fauna, especially koi fish. The variety of life in God's creation is very interesting to be used as an idea for creating art, one of which is the koi fish. The attraction of koi fish lies in the variety of patterns, colors, and movements that are captivating. Judging from its existence, koi fish have long been a part of human life, from the imperial era in China and Japan several centuries ago to the present. The beauty of koi fish is an attraction for humans to own, maintain, even as part of a lifestyle that can improve economic status and social status. For the writer's life, koi fish is one part of a hobby that since childhood, can bring fun and entertainment, calm the soul, as well as a source of inspiration in creating painting. These works of art can add to the richness of the repertoire of visual arts in Indonesia, in terms of the concepts, media, and techniques that are revealed. The method used in this research is the first observation or direct observation of the object under study, data collection through interviews, the internet, books, and data analysis. While the method of creation used is exploration, experimentation and creation of works. From these methods, six works were realized, including: 1. Tanco and the Japanese Flag, 2. Samurai Shiro, 3. Gosanke Worldwide, 4. Peace and Calm, 5. Victory, 6. The King of Ornamental Fish. In realizing a work, it is viewed from two aspects, namely ideoplastic aspects and physioplastic aspects. The benefit of this creation is that the public can appreciate this painting, both in terms of aesthetics and ethics.