Artificial Baits Research Articles

Activity patterns of Octopus tetricus (Mollusca: Cephalopoda) and their behavioural responses to fisheries trap and bait combinations

An understanding of octopus behaviour and their capture by fishing gears is required to inform efficient, sustainable, and ethical octopus fisheries. Here, the behaviour of Octopus tetricus was assessed in response to different bait and trap combinations in an outdoor mesocosm experiment. Eight wild octopuses were collected, maintained in individual tanks with flow-through seawater and aeration, and monitored with a 24-h video surveillance system. Six different traps and four different baits were presented to each octopus in various combinations during four sequential trials. Fine-mesh crab traps were the most successful in capturing octopus, accounting for 23 of the total 30 captures across all trials. Whereas solid trigger traps produced the greatest number of other interactions (e.g., octopus sitting on trap/in the entrance), averaging 43 interactions per trial, but were rarely triggered. Bait type did not influence octopus capture, trap interaction frequency, or octopus activity; however, only artificial bait types were trialled, and fresh natural baits may elicit a stronger response and should be investigated in future research. Generally, octopus were inactive, dedicating only 9.5% of their total time to active behaviours. Octopus activity varied with time of day, with peak activity during morning daylight (0800–1200) and the lowest activity during the dark hours of the very early morning (0000–0400). Additionally, capture numbers, trap interactions, and activity varied among individuals, with bolder personalities in some octopus. This natural variation among individual octopuses may lead to fishery-induced selection associated with the elevated capture frequency of bold or more active individuals.

Mammal dung-dung beetle trophic networks: an improved method based on gut-content DNA.

Dung beetles provide many important ecosystem services, including dung decomposition, pathogen control, soil aeration, and secondary seed dispersal. Yet, the biology of most dung beetles remains unknown. Natural diets are poorly studied, partly because previous research has focused on choice or attraction experiments using few, easily accessible dung types from zoo animals, farm animals, or humans. This way, many links within natural food webs have certainly been missed. In this work, we aimed to establish a protocol to analyze the natural diets of dung beetles using DNA gut barcoding. First, the feasibility of gut-content DNA extraction and amplification of 12s rDNA from six different mammal dung types was tested in the laboratory. We then applied the method to beetles caught in pitfall traps in Ecuador and Germany by using 12s rDNA primers. For a subset of the dung beetles caught in the Ecuador sampling, we also used 16s rDNA primers to see if these would improve the number of species we could identify. We predicted the likelihood of amplifying DNA using gut fullness, DNA concentration, PCR primer, collection method, and beetle species as predictor variables in a dominance analysis. Based on the gut barcodes, we generated a dung beetle-mammal network for both field sites (Ecuador and Germany) and analyzed the levels of network specificity. We successfully amplified mammal DNA from dung beetle gut contents for 128 specimens, which included such prominent species as Panthera onca (jaguar) and Puma concolor (puma). The overall success rate of DNA amplification was 53%. The best predictors for amplification success were gut fullness and DNA concentration, suggesting the success rate can be increased by focusing on beetles with a full gut. The mammal dung-dung beetle networks differed from purely random network models and showed a moderate degree of network specialization (H2': Ecuador = 0.49; Germany = 0.41). We here present a reliable method of extracting and amplifying gut-content DNA from dung beetles. Identifying mammal dung via DNA reference libraries, we created mammal dung-dung beetle trophic networks. This has benefits over previous methods because we inventoried the natural mammal dung resources of dung beetles instead of using artificial mammal baits. Our results revealed higher levels of specialization than expected and more rodent DNA than expected in Germany, suggesting that the presented method provides more detailed insights into mammal dung-dung beetle networks. In addition, the method could have applications for mammal monitoring in many ecosystems.

Kajian tentang jenis umpan buatan pancing tonda terhadap hasil tangkapan

The aim of this research is to determine the differences between two types of artificial bait on troll line on catches and to identify the composition of catch types based on bait type. This research was carried out in Tanawangko waters and was carried out from February to March 2023 using the experimental fishing method, where two pancing tonda each using silk fiber and chicken feather bait were operated simultaneously in one boat for 5 trips which were then analyzed using the t test. The catch during the research was 24 individuals with 3 species, namely with silk fiber bait, 20 individuals were caught consisting of 3 species and using chicken feather bait, 4 individuals were caught consisting of 2 species. The analysis results show that tcount = 1.684 < t table = 2.776; so it accepts H0 and rejects H1. This explains that the use of chicken feather bait is not significantly different from silk fiber as trolling bait for catch results. The conclusion of this research is that using silk fiber bait resulted in more catches than chicken feather bait, but the results of the t test analysis showed that the two were not significantly different and the three species of fish caught were 15 skipjack tuna (Katsuonus pelamis), 7 baby tuna (Thunnus sp.), and 2 lemadang (Coryphaena hippurus).

Penerapan Metode Logika Fuzzy Mamdani Untuk Menentukan Jumlah Pendapatan Penjualan Produk Umpan Pancing

Anugerah Jaya Finishing Store 99 is one of the online stores that sells fishing bait. Fishing bait is a crucial factor in improving the efficiency of fish capture, and there are two types of fishing bait : artificial bait and natural bait. Income is the money generated from the sale of goods or services to costumers and is the most important aspect in determining the smooth operation of a business. To determine the amount of income in this study, one of the fuzzy logic methods, namely mamdani fuzzy logic, was used. Mamdani fuzzy logic was chosen because it is the method that is most similar to human logic.

Effects of behavioral strategies on catchability, bait selectivity, and hunting behavior in northern pike (Esox lucius)

This study investigated how northern pike with two behavioral strategies in the context of predation interact with natural and artificial baits in simulated angling experiments. Predator types were assessed in three behavioral trials over 15 days by measuring foraging latency under altered conditions (abruptly increased light intensity). Latency revealed fast and slow predator responses showing high individual repeatability, interpreted as proactive and reactive predator types, with reactive individuals adapting their response over time. Both types displayed similar hunting performances in predation trials with live prey under habituated conditions. In angling trials, proactive pike expressed significantly more predation than reactive pike, independent of bait type. During angling trials, predator type did not affect bait handling, while both predator types developed strong sequential bait avoidance, indicating a learning effect. Angling trials did not affect hunting for live prey. The results suggest that pike exhibit individual differences in responses to environmental changes linked to their predatory behavior. Angling selection may play a role in pike populations, with the proactive predator type more likely to be hooked than the reactive type.

Host-plant phenology mediates facultative ant mutualism in the rare butterfly, Celastrina humulus (Lepidoptera: Lycaenidae).

Host-plant phenology can directly and indirectly mediate the abundance of insect herbivores. Our objective was to determine how host-plant flowering phenology shapes a facultative ant-lycaenid mutualism. The focus of our research was the hops azure, Celastrina humulus Scott & D. Wright, a rare species whose larvae feed on the pollen-bearing inflorescences of Humulus lupulus var. neomexicanus. We used several approaches to evaluate the role of host-plant flowering phenology in this system. First, we monitored larvae over three study years (2020-2022) to parse the role of host-plant flowering phenology and other factors in shaping the likelihood of ant tending. Second, we tested larval performance at various phenological stages of the host plant. We also quantified variation in soluble proteins and secondary metabolites among inflorescences at varying phenological stages. Lastly, we treated artificial sugar-protein baits with extracts from different phenological stages of the host plant; this allowed us to assess how chemical variation among stages could impact ant recruitment. Monitoring results revealed that the likelihood of ant tending was lowest for larvae on host plants with early-stage inflorescences. These floral stages had the greatest concentrations of both soluble proteins and α-acids (humulone and cohumulone), and in the feeding trial, early-stage flowers enabled greater weight gain for larvae. However, extracts from early-stage flowers reduced ant recruitment to sugar-protein baits. Altogether, these results suggest that early-stage inflorescences enhance larval growth while also reducing the recruitment of mutualist ants. This shows an indirect mechanism whereby changing host-plant phenology can mediate herbivore populations through interactions with ants.

Investigating possibilities in attracting invasive green anoles with live and artificial baits

Traps are often used as effective tools for eradicating invasive predators. Traps with baits are more effective than those without baits, and live baits are expected to be more effective than artificial ones. However, keeping live baits fresh is often difficult and labour-intensive; thus, artificial baits are to be desired. In this study, we verified the effectiveness of live and artificial baits with or without movement in attracting the invasive green anole Anolis carolinensis. We conducted behavioural experiments in a laboratory with four treatments (live flies, artificial flies without movement, artificial flies with movement and no bait). We placed one of the four bait treatments in a transparent square tube and observed whether a green anole entered the tube (i.e., was attracted) within 30 min. Bait effectiveness was evaluated by comparing the number of attracted and unattracted individuals to that of the control. Green anoles were attracted to live flies but not to artificial flies with or without movement. Our study confirmed that live baits are useful as attractants for green anoles. Artificial baits and those with movement were not attractive, probably because of their monotony. Artificial baits with more complex movements can possibly attract green anoles, and future studies investigating this possibility are needed.

Stand-level habitat characteristics and edge habitats drive biological pest control services in the understory of oil palm plantations

The expansion of oil palm agriculture in the tropics has gone hand in hand with a sharp increase in synthetic pesticide application in the region. Due to associated negative ecological impacts, there is growing pressure on the oil palm industry to reduce chemical usage and revert to natural pest control methods. However, knowledge of the mechanisms that govern how successful natural predators are at controlling pest insect species in the understory of oil palm plantations is scarce. By using an artificial caterpillar bait method this study examines the effectiveness of three animal taxa (i.e., arthropods, birds, and mammals) as within-plantation insect predators. Caterpillars were deployed across three different aged oil palm plantation plots in Selangor, Malaysia. Data for height and coverage of understory vegetation, plot location, elevation, and canopy cover were collected. Of the three taxa studied, mammals were responsible for the highest levels of predation, followed by arthropods and then birds. Arthropod predation was higher at edge locations, in abandoned habitats and in elevated areas. Mammal predation was shown to increase with increasing understory coverage and decrease with increasing elevation. Bird predation was not shown to be associated with any of the habitat quality characteristics studied. We found that overall predation pressure was higher at the edge of plantations compared to within plantation interiors, and that overall predation positively correlated with an increase in understory vegetation coverage. Management strategies that enhance undergrowth coverage and maximise edge habitats have the potential to boost the effectiveness of natural predators in the understory of oil palm plantations.

Soap application alters mosquito-host interactions

To find nutrients, mosquitoes use volatile organic compounds (VOCs) emitted by plants and animal hosts. These resources overlap in their chemical composition, and an important layer of information resides in VOCs' relative abundance in the headspace of each resource. In addition, a large majority of the human species regularly uses personal care products such as soaps and perfumes, which add plant-related VOCs to their olfactory signature. Using headspace sampling and gas chromatography-mass spectrometry, we quantified how human odor is modified by soap application. We showed that soaps alter mosquito host selection, with some soaps increasing the attractiveness of the host and some soaps reducing it. Analytical methods revealed the main chemicals associated with these changes. These results provide proof-of-concept that data on host-soap valences can be reverse-engineered to produce chemical blends for artificial baits or mosquito repellents, and evince the impact of personal care products on host selection processes.

Characterization of bluefish baits (keeled mullet, leaping mullet, and sardine) in regard to biochemical and physical properties: bait preference of bluefish

The fishing industry needs alternative baits that are not based on resources available for human consumption. In order to develop artificial baits, first the preferred baits should be determined, and then their biochemical and physiological composition should be identified. The aim of this study was to determine bluefish bait preferences and reveal the biochemical composition and physical characteristics of the preferred baits. In this study, keeled mullet, leaping mullet, and sardine species were found to have the highest catch, respectively. The highest texture hardness and whiteness colour values were found in keeled mullet, which had the highest catch efficiency for bluefish fishing. The highest palmitoleic acid content was found in keeled mullet at 25.86% (16.93% in leaping mullet and 17.05% in sardine). However, the highest PUFA content was found in sardine (15.56%), followed by leaping mullet (13.97%), and then keeled mullet (11.32%). As for the amino acid compositions, it was determined that glutamic acid and serine content, which are known to have positive effects on feed intake, were higher in keeled mullet. In regard to volatile components, mullet species were especially rich in total alcohol, aldehyde, ketone, and amines, while sardines were rich in hydrocarbons and furans. Hexanal and heptanal compounds, known as fish aroma, were determined at high rates in keeled mullet. It can be concluded that these components may be attractive to bluefish. The data presented in this study may be useful for the production of artificial bait.

Reprodução do black-bass invasor Micropterus salmoides (Lacepède, 1802) em um reservatório neotropical, com sugestões para manejo e controle

Abstract Aim The largemouth bass Micropterus salmoides was introduced in more than 50 countries for the purpose of sport fishing. In Brazil, records date from 1922, and nowadays many populations are known to occur in the southern region. Here we investigated the reproductive biology of this species in a small reservoir in southern Brazil, to understand the role of the reproductive strategy in the invasion process and assist in its management. We conclude with suggestions for the management in local scale, as this species can bring relevant problems to the public supply through trophic cascade and other negative effects. Methods Samples were performed with different methods, between May 2011 and April 2012. All fishes were measured, and the reproductive season was determined through the relative frequency of reproductive stages and the gonadosomatic index. Sex ratio was calculated monthly and for each total length (TL) class and compared with the estimates presented in the literature. Total length at maturity (L50, length at which 50% of the individuals were mature) was estimated for females, males and the entire study population. Results A total of 565 individuals of M. salmoides were analyzed. Overall sex-ratio did not differ significantly. The monthly distribution of the gonadosomatic index for females and males showed higher values between August (late winter) and November 2011 (austral spring). ��-Binomial modelling of sex-ratio data of native (n=1) and introduced populations (n=7) showed a lower proportion of females in its native range. All individuals > 21.5 cm TL were mature (L95), and L50 was calculated at 18.7 cm TL. After the reproductive period, an increase in the abundance of young individuals (≤ 7.0 cm TL) was registered, corresponding to 50% of all individuals collected. The relative frequency of mature individuals and the variation in the gonadosomatic index indicate a prolonged spawning period during the austral spring, coinciding with the increase in temperature. Conclusions Results suggested that some changes in life history traits, such as the early sexual maturation and the long reproductive period, coupled with a remarkable adaptability, may have facilitated the establishment of M. salmoides populations in this reservoir. The illegal and intentional stocking by anglers plays a central role in the introduction and dispersal of M. salmoides in Brazil. We encourage studies on the sanitary quality of this fish for human consumption, so that massive campaigns of education the population to encourage capture and consumption are implemented by the competent authorities as a control measure in local scale, combined with targeted samplings with artificial baits during the reproductive period, identification, and removal of nests and fingerlings using electric fishing or trap nets during the recruitment period.

重复垂钓对鲫幼鱼易钓性和能量代谢及个性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 重复垂钓对鲫幼鱼易钓性和能量代谢及个性的影响 DOI: 10.5846/stxb202106201635 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(31300341);重庆市自然科学基金项目(cstc2021jcyj-msxm0498);重庆市教委科学技术研究项目(KJQN201900540, KJQN202000539) Effects of repeated angling on vulnerability to angling, energy metabolism and personality of juvenile crucian carp (Carassius auratus) Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:先捕后放是一种重要的鱼类资源保护策略和渔业管理手段。经历先捕后放的被钓鱼类个体的生理与行为会发生变化。当这些个体再次面对人工垂钓诱饵时,可能会呈现更加谨慎的摄饵或鱼钩回避行为。为考察重复垂钓对鱼类易钓性、能量代谢和个性的影响,本研究以鲤科鱼类鲫(Carassius auratus)幼鱼为实验对象,在(25.3±0.1)℃水温条件下对垂钓组和对照组进行3次的能量代谢(标准代谢率,SMR;最大代谢,MMR)和个性(勇敢性、活跃性)测定。其中,垂钓组需进行垂钓实验,而对照组不进行任何垂钓操作。研究发现:(1)重复垂钓显著降低鲫幼鱼的垂钓率,但明显增加单尾平均垂钓时间和整体死亡率。(2)重复垂钓降低鲫幼鱼的体重、肥满度、SMR、MMR、代谢空间(AS)和相对代谢空间(FAS),但整体上不影响勇敢性和活跃性。(3)在测定Ⅰ中,高易钓性个体的体长和开阔区运动时间比大于低易钓性个体,但前者的肥满度小于后者。然而,在测定Ⅱ和Ⅲ中,高易钓性个体的形态参数、能量代谢、个性(勇敢性和活跃性)与低易钓性个体并无差异。研究表明:重复垂钓明显降低鲫幼鱼的易钓性,并且种内个体易钓性的变化方向不尽相同;重复垂钓对鲫幼鱼的形态和有氧代谢能力产生负面影响,可能降低了其用于运动、生长和消化等生理功能的代谢潜能。 Abstract:Catch and release is very popular as fish conservation strategy and fisheries management. The individuals who experience catch and release will have substantial changes in their physiology and behavior. When these individuals are faced with artificial bait again, they may show more cautious bait-taking or hook avoidance behavior. In order to investigate the effects of the repeated angling on vulnerability to angling, energy metabolism and personality of the Cyprinidae, juvenile crucian carp (Carassius auratus) was used for the animal model in our study. The morphology, metabolic rate (e.g., standard metabolic rate, SMR; the maximum metabolic rate, MMR) and personality (e.g., activity and boldness) of both the angling and control group were measured three times at (25.3±0.1) ℃. The individuals of the angling group were subjected to an angling experiment at each trial while fish in the control group did not experience any angling operation. The results show that the angling rate decreased significantly and the average individual angling time increased significantly as the increased of angling times. Repeated angling resulted in a higher death rate in the angling group compared to the control group. The body mass, condition factor, SMR, MMR, aerobic scope, and factorial aerobic scope were significantly decreased by the repeated angling in the angling group compared to the control group, but there were no changes in boldness and activity after the repeated angling. During the first test, high vulnerability to angling phenotype (HVA) had larger body length and movement time in open area, lower condition factor compared to low vulnerability to angling phenotype (LVA). However, during the second and third test, no difference in morphology parameters, energy metabolism, and personality (e.g., boldness, activity) could be detected between the HVA and LVA. Our study suggests that the repeated angling reduces the vulnerability to angling in juvenile crucian carp, and the change direction in vulnerability to angling are different among groupmates with the angling group. Repeated angling decreases aerobic scope of the juvenile crucian fish, which may reduce potential metabolic scope for physiological functions such as exercise, growth and digestion, and ultimately reduce the survival fitness of the individual. 参考文献 相似文献 引证文献

Efektivitas Pemanfaatan Rumpon Sebagai Alat Bantu Penangkapan Ikan pada Nelayan Lokal di Kelurahan Hamadi Kota Jayapura

Rumpon (Fishing Aggregating Devices/FADs) are fishing aids to lure fish to gather in an area. The use of FADs by Hamadi fishermen in Jayapura City is carried out by individual local fishermen with hand line fishing gear. This study aims to: 1) Know the composition of the catch (type and number of fish) on FADs, 2) Compare the effectiveness of FADs and fishing gear. This study used Qualitative and Quantitative Methods, data collection techniques consisted of a) Observation, b) Interview and c) Documentation study, analysis and to determine the composition of the catch, the effectiveness of FADs and the effectiveness of fishing gear. The results showed that the composition of the catch on FADs consisted of 19 species with 1,037 individuals per species, the highest species composition was found in Selar boops, which was 17.65% (183 individuals) and the lowest was found in Lutjanus Buccanella, namely 1.25% (13 individuals). . The highest effectiveness of assisted FADs was on Basic FADs, namely 60.46% (627 individuals) and the lowest on surface FADs, namely 39.54% (410 individuals), while the highest effectiveness of fishing gear used artificial bait, namely 53.81% (558 individuals) and the lowest was on natural baits namely 46.19% (479 tails). The conclusion is that the dominating fish species are Selar boops, bottom FADs are more effective than surface FADs, while the more effective fishing gear is using artificial baits.

DIFFERENT BAIT AND HOOK SIZE EFFECT ON MACKEREL CATCHES WITH HANDLINE IN CILACAP WATERS, CENTRAL JAVA PROVINCE, JAVA ISLAND

Hand line is a fishing gear commonly used by fishermen in Cilacap Regency to catch schools of mackerel fish. Hand line is a passive fishing gear. Mackerel is a fishery commodity that has high economic value. The construction of handline fishing gear is a plastic reel, fishing line, branch line, swivel and hook. The fishing line area is in the IB fishing line. Handlines are operated in areas with a depth of 10-15 meters. Cilacap fishermen generally operate handlines not to the bottom of the waters. The purpose of this study was to determine the difference in the catch of mackerel based on the difference in bait and hook size of handline fishing gear. The experimental method in this study used 2 variables, namely differences in bait and hook size with 6 repetitions. The bait used in this study was natural (live) bait and artificial (dummy) bait in the form of squid, as well as the size of the hook, namely fishing line size 4/0 with 6/0. The overall catch on the handline fishing gear operated was 17 mackerel fish. Based on the tests that have been carried out on the catch composition using the Two Way Anova SPSS 24 test, the results show that there is no significant difference (p>0.005) on the type of bait used on catching mackerel fish. Howeever there is a significant difference (p<0.05) on the hook size used on catching mackerel fish. These results indicates that hook size acts as an important role that may affect the catching quantity of mackerel fish. The research also indicates that there is no correlation between the 2 factors (type of bait and hook size) on the overall catch of mackerel fish in Cilacap Waters.

Farklı Yemlerin (Teke Karidesi (Palaemon serratus Pennant, 1777), Morio Kurdu (Zophobas morio Fabricius, 1776) ve Afrika Göçmen Çekirgesi (Locusta migratoria L. 1758)) Olta Balıkçılığında Av Verimliliğine Etkilerinin Karşılaştırılması

Olta balıkçılığında hedef balık türlerine ve habitatlara göre canlı, cansız ve yapay yemler kullanılmaktadır. Bu çalışmada, Hexapoda türlerinden Morio Kurdu (Zophobas morio Fabricius, 1776) ve Afrika Göçmen Çekirgesi (Locusta migratoria L. 1758)’nin denizde olta balıkçılığında kullanılabilirliği ve av verimlilikleri Teke Karidesi (Palaemon serratus Pennant, 1777) ile karşılaştırmalı olarak test edilmiştir. Çalışma, Yelkoma Dalyanı’nda (Adana-Türkiye), toplam 420 olta operasyonu gerçekleştirilmiş ve 80 adet balık (72 adet çipura, 8 adet levrek) yakalanmıştır. Çipuraların % 45’i Teke Karidesi ile %33’ü Afrika Göçmen Çekirgesi ile ve %22’si Morio Kurdu ile, Levrek balığının da %75’i Afrika Göçmen Çekirgesi ile %25’i de Morio Kurdu ile yakalanmıştır. Oltaların ortalama CPUE değeri 0,003 (iğne/balık/saat) ve YPUE değeri de 0,327 (iğne/g/saat) olarak belirlenmiştir. Balıkların toplam ağırlıkları üzerinden yapılan Birim Maliyet Hesabına göre, en düşük maliyete sahip olan yemin Afrika Göçmen Çekirgesi olduğu belirlenmiştir.

Investigation on the coacervation of fish scale gelatin hydrogel with seafood waste hydrolysates for the development of artificial fish bait: Physico-chemical, thermodynamic, and morpho-structural properties

The study dealt with the development of biopolymer based hydrogel artificial fish bait with hydrolysates derived from fish processing wastes. Fish scale gelatin (FSG) was used for the development of a hydrogel to which bioattractants extracted from seafood processing wastes of fish, squid and shrimp were added to prepare composite gels such as FSG-FH, FSG-SH and FSG-SPH, respectively. To understand the homogenesity and cross linking complexation of composite gels, the study aimed at investigating physico-chemical, thermodynamic, molecular and structural properties were analysed. The gel strength, melting point and thermal stability of the composite hydrogels were found to decrease marginally compared to the control gel, FSG. It could be understood that the crystalline structure at 2θ = 23° of the FSG-SH, and FSG-FH were not much altered compared to FSG gel. However, alteration in the crystalline structure in FSG-SPH was evident at 2θ = 27.3°. The TGA and DSC analysis revealed the reduction in the thermal stability of FSG on the addition of protein hydrolysates in the process of coacervation to get hydrogel based fish bait. Further, FESEM and AFM analysis indicated FSG-SH as the composite hydrogel with most compact and smooth surface was evident by Ra and Rq values. Among the composite gels, FSG-SH was found to have higher hydrophobicity due to enhanced gel structure. FTIR spectra of FSG and composite gels exhibitted similarity corresponding to amide-A, B, I, II and III bands. However, NMR analysis revealed the existence of notable difference with respect to chemical shift in the range of 7.0–7.75 ppm expressing the presence of aromatic protons of the amino acid phe and N–H protons of amide in all the composite gels. Further, NMR analysis confirmed the role of imino acids (δ CH2 & β CH2 protons) and hydrophobic amino acids (α-CH2 protons) in decrease the physical and thermal properties of the composite gels. The addition of protein hydrolysates with FSG was found to decrease the physical, thermal and structural properties, however improve the aromatic compounds of the composite gels.

The Effect of Differences Color of Artificial Bait on Sepioteuthis lessosiana catches using Hand Line

Hand Line is a traditional fishing gear that commonly used by a fisherman in the Panggang Island, Kepulauan Seribu to catch bigfin reef squid (Sepioteuthis lessosiana). The purpose of this research is to analize the effect of color differences on artificial bait to catchment product of squid and to determine the bait’s colors that produce the most catches of squid. This research was conducted through an experimental method using a randomized block design (RAK) for 14 repetitions. Total of catches that earned amounted to 268 individuals (32,1 kg) consisted of 79 individuals (9,1 kg) caught with artificial baits orange color combination of white, 57 (7,7 kg) caught with artificial baits green color combination of white and 132 individuals (15,3 kg) caught with artificial bait color combination of red and white

The Effect of Bait Types on the Catch of Bottom Long Line in Bantan Sari Village Bantan District Bengkalis Regency

The main factor for the success of bottom longline fishing depends on the type of bait, both natural bait and artificial bait. The bait serves as an attractant for the target fish so that it is attracted to prey on it. In this study, the bait used was a machete, puput, and layur fish. The purpose of this study was to determine the amount, weight, and type of catch based on the appropriate type of bait so that it can be a reference for fishermen for optimal use of bait in the operation of longline fishing gear. This research was conducted in February 2022, located in the waters of Bantan Sari Village, Bantan District, Bengkalis Regency. The method used is the experimental fishing method, by operating the fishing gear directly and analyzing using the analysis of variance and the Least Significant Difference test. Based on the research, the catches obtained were debuk fish, gelama , stingrays, and puffer, with the highest catches in terms of weight, namely stingrays as much as 61800 g.

Characterizing Sea Turtle Bycatch in the Recreational Hook and Line Fishery in Southeastern Virginia, USA

Although commercial hook and line fisheries pose a well-documented and significant threat to worldwide sea turtle populations, recreational hook and line fisheries remain understudied. This article describes information from sea turtle bycatch reported from interactions in the recreational hook and line fishery, as well as survey results from recreational anglers in Virginia from 2014 through 2018. Reports of interactions increased annually during the study with Kemp's ridley sea turtles (Lepidochelys kempii) reported most frequently (n = 162), followed by 45 loggerheads (Caretta caretta), 6 green turtles (Chelonia mydas), and 39 unidentified sea turtles. Commonly encountered bait types were similar between surveyed anglers and bait used during turtle interactions, with significantly more squid bait noted during turtle interactions (51%) than used by surveyed anglers (29%) (χ2 = 41.32, p < 0.0001). Additionally, bloodworms and artificial bait were encountered comparatively less frequently during turtle interactions. Overall, interactions with the hook and line recreational fishery in Virginia appear opportunistic and involve otherwise healthy animals, presenting limited means for mitigating sea turtle bycatch. In the absence of regulatory oversight of bycaught sea turtles in the recreational fishery, mitigating injury from these interactions through targeted outreach provides a short-term solution to reducing the severity of these inevitable interactions.

Perspectives on Odor-Based Control of Tsetse Flies in Africa.

Tsetse-transmitted trypanosomiases are among the most neglected tropical diseases in sub-Sahara Africa. Although all tsetse species are susceptible to trypanosome infections, their differential attraction/feeding preferences for different wildlife, domestic animals, and/or humans constitute critical determinants of trypanosomes species they predominantly transmit. Artificial bait technologies, based on long-range tsetse olfactory responses to natural cues emitted by preferred hosts and blends of synthetic versions that mimic these cues, have successfully been applied in attractant-odor-based (“pull” tactic) reduction of field populations of some tsetse species. Olfactory attribute associated with active avoidance of tsetse-refractory non-hosts has similarly been exploited in design of repellent-odor-based (“push” tactic) protection of livestock. These tactics have opened possibility of spatially strategic deployment of the two sets of odor baits in “push-pull” tactics. Possibility of developing blends with enhanced attraction and repellence compared with those associated with savannah tsetse fly hosts and non-hosts, respectively, have been explored, where structure activity and blends of different components generated two novel blends. The studies evaluated structure activity and blends of different components. One based on attractive constituents associated with buffalo (Syncerus caffer) comprised of ε-nonalactone, nonanoic acid, 2-nonanone (in 1:3:2 proportion) delivered together with acetone, which showed significantly better attractancy on savannah tsetse fly than the standard blend comprised of 3-propylphenol, octenol, p-cresol, and acetone (POCA). The other blend comprised of δ-nonalactone, heptanoic acid, 4-methylguaiacol and geranylacetone (in 6:4:2:1 proportion) was significantly more repellent than previously characterized blend based on tsetse fly refractory waterbuck (Kobus defassa) constituents (δ-octalactone, pentanoic acid, guaiacol and geranylacetone). So far, no effective attractants or repellents of riverine tsetse fly species have been characterized. Optimized attractant and repellent blends for savannah tsetse flies lay down useful groundwork for future development of the “push-pull” deployment tactic for area-wide control of tsetse flies. Better understanding of the physiological, cellular, and molecular basis of response in the tsetse fly to odors can potentially augment the current tsetse fly-control interventions.