Mapping and Assessing Commercial Fisheries Services in the Lithuanian Part of the Curonian Lagoon

The spatial distribution of biomass of main commercial fish species was mapped to estimate the supply of a provisioning fishery service in the Curonian lagoon. Catch per unit effort (CPUE) was used as a proxy to estimate the efficiency of commercial fishing and, subsequently, the potential biomass of fishes. The relationship between distinctive characteristics of the fishing areas and corresponding commercial catches and CPUE was analyzed using multivariate analysis. The total catch values and CPUE used in the analyses were derived from the official commercial fishery records. RDE analysis was used to assess the variation of both catch and CPUE of commercial fish species, while the percentages of bottom sediment type coverage, average depth, annual salinity, and water residence time in each of the fishing squares were used as explanatory variables. This distance e-based redundancy analysis allowed for the use of non-Euclidean dissimilarity indices. Fisheries data spatial distribution map indicated the lack of coherence between the spatial patterns of commercial catches and CPUE distribution in the northern part of the lagoon. Highest CPUE values were estimated in the central-eastern part of the lagoon as compared to the western part of the lagoon where CPUE values were substantially lower. Both total catch and CPUE appeared not to be related to the type of bottom habitats statistically while being spatially correlated in-between. However, the impact of salinity and water residence time calculated using the 3D hydraulic circulation model on the distribution of both CPUE and commercial catches was statistically significant.

The analysis of alder pollen season in selected cities of Poland in 2021

The study aims to monitor the alder pollen season in selected Polish cities: Bialystok, Cracow, Lublin, Olsztyn, Opole, Piotrkow Trybunalski, Sosnowiec, Szczecin, Warsaw, Wroclaw and Zielona Gora in 2021. Pollen concentrations were recorded by volumetric method using a Burkard-type sampler operating in a continuous volumetric mode. Alder pollen season, defined as the period with 98% of the annual total catch, started in 3rd decade of February in all monitoring sites. There was a marked variation in duration of the season between the sites. It lasted from 31 in Cracow to 54 days in Bialystok (38 days on average). The highest peak daily alder pollen concentrations were observed in Wroclaw (1879 grains/m3) on February 26th). The longest exposure to high concentrations of alder pollen, lasting 22–24 days, was detected in Zielona Gora, Piotrkow Trybunalski and Olsztyn. The alder pollen season in 2021, compared to the previous year, was longer, with higher average sum of daily concentrations over the season, higher maximum daily concentrations and longer exposure to high pollen concentrations at most monitoring sites.

Analysis of Crayfish Catches Using Bubu Wau in Laut Tawar Lake, Central Aceh, Aceh

Laut Tawar Lake is located in the town of Takengon, Central Aceh district. Currently, Laut Tawar Lake has been utilized by the surrounding community as a fishing spot. One of the fishing gears used by fishermen is Bubu wau. One of the catches obtained by fishermen is crayfish. The crayfish has a high economic value, so the lack of control over the intensity of the catch also causes the average size of the crayfish caught, because catching crayfish is a transition from catching Rasbora tawarensis. One of the problems that frequently occur and research on crayfish has never been done before. Therefore, this research needs to be done. The purpose of this study was to determine fishing catch compositions of Bubu wau and the size distribution of crayfish carapace length of Bubu Wau fishermen in the Teluk One-one, Laut Tawar Lake. The research was carried out in about March 2021. The description of the fishing catch composition was analyzed by using the describded method. The size distribution of crayfish carapace length was analyzed by the Sturgess rule. From the results of the study, it can be concluded that the catch compositions of Bubu wau in Teluk One-one are crayfish, suckermouth catfish, channeled apple snail and tilapia. The type of crayfish caught by fishermen’s Bubu wau was Cherax quadricarinatus amount of 4232 individuals (89% of the total catch), where the total length of the dominant crayfish carapace was 4.4-4.9 cm with a total number of 1403 and the least with a size of 8.6-9.1 cm was 1 crayfish from the total catch

Catch Composition of Set Net Fisheries during Normal Season in Sungai Sembilang Waters, Selangor, Malaysia

Highlight ResearchThe Set Net was identified and recorded.Length and weight of the catch of set net was analyzed. AbstractSet net fisheries are made according to traditional fishing gears method in the coastal waters of Sungai Sembilang, Selangor, Peninsular Malaysia. These fisheries system are the passive structure of gear used to catch fish that swim in shallow water with muddy substrate. This study focused on determining the species variety and the possible future of set net fisheries in Sungai Sembilang. Catch composition of set net was investigated based on the catch data during July to December 2020 and continued from January to February 2021. The catch data was recorded by a research assistant on site during fishing season. The data consist of species, length and weight of all catches recorded. Total catch of 60 fish species belonging to 23 families were captured during this study period. Ariidae (31.73%), Clupeidae (11.56%), and Scatophagidae (7.96%) were determined as dominant families caught this set net. The total dominant catch amount of species Plicofollis argyropleuron (18.71%), Nemapteryx caelata (9.96%), and Anodontostoma chacunda (8.92%) compromised 37.6% of the total catch. This type of fishing gear can be used by local fisherman to catch fishes and can prevent trawl net from come closer to the shore. This study would provide some general useful information about the status of set net fisheries as well as the species abundance caught from the set net.

The Effectiveness of Melaleuca bracteata Oil Formula on Trapping of Fruit Fly Pests (Bactrocera spp.)

<p> </p><p>Fruit flies (<em>Bact</em><em>r</em><em>ocera</em> spp) can cause yield losses of 30-40% of the horticultural product and even crop failure. One way to control is to use an attractant with the active ingredient methyl eugenol<span style="text-decoration: line-through;">.</span> The objective of the research was to identify the catching ability and the durability of the formula on trapping fruit flies. It was conducted from October 2020 to March 2021 in orchards in the Bogor area, designed in a randomized block with 8 treatments and 3 replications. The treatments consisted of oils: (1) nutmeg, (2) cloves, (3) citronella, (4) palm, (5) melaleuca + nutmeg, (6) melaleuca + cloves, (7) melaleuca + citronella, (8 ) melaleuca + palm (1:1 ratio). As much as 1 ml of oil is dropped on a cotton swab in a trap bottle and hung on a fruit tree. Observations were made every 5 days by counting the number, type of flies, and sex of the flies trapped. It showed that nutmeg and clove oil were able to trap 5 and 7 fruit flies in the first 5 days, but subsequently no flies were trapped, while citronella and palm oil were unable to trap fruit flies. A mixture of melaleuca oil containing 84.86% methyl eugenol with nutmeg, citronella, and palm oil was able to trap fruit flies for about 3 months with a total catch of 2.479; 2.434; and 2.487, respectively, while the mixture of melaleuca+cloves was able to trap fruit flies for 4 months and was able to trap 2 female flies<span style="text-decoration: line-through;">.</span></p><p><strong>Keywords</strong>: Attractant, <em>Bactrocera</em> spp., <em>Melaleuca bracteata</em>, methyl eugenol</p><p> </p><p><strong>Abstrak</strong></p><p><strong>Efektivitas Formula Minyak <em>Melaleuca bracteata</em> Terhadap Daya Tangkap Hama Lalat Buah (<em>Bactrocera</em> spp.)</strong></p><p>Lalat buah (<em>Bact</em><em>rocera</em> spp) dapat menimbulkan kehilangan hasil sebesar 30–40% pada produk hortikultura, bahkan gagal panen. Salah satu cara pengendaliannya adalah dengan menggunakan atraktan (pemikat) berbahan aktif metil eugenol (C₁₁H₁₄O₂)<em>. </em>Penelitian ini bertujuan untuk mengetahui daya tangkap dan daya tahan formula dalam memerangkap hama lalat buah. Penelitian dilakukan pada bulan Oktober 2020 sampai Maret 2021 di kebun buah-buahan (rambutan, jambu biji, dan jambu air) di Bogor, dengan rancangan acak kelompok 8 perlakuan dan 3 ulangan. Perlakuan terdiri dari minyak : (1) pala, (2) cengkeh, (3) serai wangi, (4) sawit, (5) melaleuca + pala, (6) melaleuca + cengkeh, (7) melaleuca + serai wangi, (8) melaleuca + sawit (dengan perbandingan 1 :1). Sebanyak 1 ml minyak diteteskan pada kapas di dalam botol perangkap dan digantungkan pada pohon. Pengamatan dilakukan setiap 5 hari terhadap jumlah, jenis dan jenis kelamin lalat yang terperangkap. Hasil menunjukkan bahwa minyak pala dan cengkeh mampu memerangkap lalat buah sebanyak 5 dan 7 ekor berturut-turut pada 5 hari pertama, namun selanjutnya tidak ada lalat yang terperangkap, sedangkan minyak serai wangi dan sawit tidak mampu memerangkap lalat buah. Campuran minyak melaleuca yang mengandung metil eugenol 84,86% dengan minyak pala, serai wangi dan sawit mampu memerangkap lalat buah selama sekitar 3 bulan dengan total tangkapan sebesar 2,479; 2,434; dan 2,487 ekor per perangkap berturut-turut, sedangkan campuran Melaleuca dengan cengkeh mampu memerangkap lalat buah selama 4 bulan dan mampu memerangkap 2 ekor lalat betina, walaupun dengan jumlah tangkapan yang lebih rendah (2,078 ekor) daripada perlakuan lain.</p><p><strong>Kata kunci</strong> : Atraktan, <em>Bactrocera</em> spp., <em>Melaleuca bracteata, </em>metil eugenol</p>

Assemblage Structure of the Ichthyoplankton and Its Relationship With Environmental Factors in Spring and Autumn off the Pearl River Estuary

Ichthyoplankton assemblages and their relationship with environmental variables are investigated in waters off the Pearl River Estuary in spring and autumn of 2019. Of 80 ichthyoplankton taxa identified using DNA barcode and morphological methods, 61 are identified to species. The most abundance families (Carangidae, Trichiuridae, Mullidae, and Scombridae) account for 61.34% of the horizontal total catch in spring, while Menidae and Carangidae are the most abundant families identified in autumn, accounting for 89.72% of the horizontal total catch. Cluster analysis identifies three species assemblages in spring, and four in autumn based on horizontal trawls. Relationships between assemblage structure and environmental variables (in situ and remote sensed) are determined by canonical correspondence analysis. Ichthyoplankton assemblage structure appears to be strongly influenced by sea level anomalies, salinity, water depth, temperature at 10 m depth, and distance from shore. We demonstrate the efficacy of using DNA barcode to identify ichthyoplankton, and suggest how these data can be used to protect fish spawning grounds in waters off the Pearl River Estuary.

The effect of insecticide application by dropleg sprayers on pollen beetle parasitism in oilseed rape

Dropleg sprayers apply pesticides below the flower horizon of oilseed rape plants and thus reduce unwanted side effects on pollinating insects. Whether this technique benefits parasitoids of seed and pollen feeding insect pests has not been studied earlier. To answer this question, we first assessed the vertical distribution of pests and parasitoids using a portable aspirator. In addition, parasitism rates of pollen beetle, Brassicogethes aeneus Fabricius (Coleoptera: Nitidulidae), by the larval parasitoid Tersilochus heterocerus Thomson (Hymenoptera: Ichneumonidae) were compared in conventional and dropleg sprayed fields over four years (2016–2019), using the neonicotinoids thiacloprid and acetamiprid. Our results show that seed and pollen feeders were mainly found in the flowering canopy, while the predominant location of parasitoids was species-specific. Among pollen beetle parasitoids, Phradis interstitialis Thomson (Hymenoptera: Ichneumonidae) was more abundant below flowering canopy (63% of total catch), whereas T. heterocerus was mainly caught in the flowering canopy (84% of total catch). In the spraying experiments, average parasitism rates of pollen beetles by T. heterocerus ranged between 55 and 82% in the untreated controls. In the dropleg spray treatments, parasitism rates did not differ significantly from control levels, with the exception of thiacloprid application in 2019. In contrast, conventional spray applications resulted in a reduction of parasitism rates by up to 37% compared to the control for at least one of the insecticides in three out of four years. The impact of conventional application differed between years, which may be explained by the temporal coincidence between spray application and the immigration of parasitoids into the crop. We conclude that dropleg spraying exerts lower non-target effects on the main biological control agent of pollen beetle.

Utilization of FAD Distribution in South Buton Waters as a Fishing App by Purse Sein Fishermen in Kadatua District, Selatan Buton Regency

Fish Aggregating Devices (FAD's) have long been used by fishermen in South Buton Regency. This study aims to determine the utilization of FAD distribution as a fishing aid by purse sein vessels in the waters of Kadatua District, South Buton Regency. This study aims to determine the utilization of FAD distribution as a fishing tool by purse sein vessels in Kadatua District, South Buton Regency. Data collection methods include FAD point data taken from GPS (Global Position System) fishermen and dominant catch data from purse sein fishermen. The results of the study obtained data on the distribution of FADs in Kadatua District spread between a distance of 0-12 miles, during the study the coordinates of FADs were obtained as many as 79 coordinate points owned by fishermen in Kadatua District. FADs used by purse sein fishermen to carry out fishing operations have 24 FAD points, which are spread over a distance of 0 – 12 miles. In April the distribution of FADs used as fishing aids by purse sein vessels was at a distance of ± 0 – 12 miles, while in May and June FADs used as fishing aids were at a distance of ± 2 – 12 miles. The dominant fish catch data for purse sein fishermen is 690 kg in April, 525 kg in May and 735 kg in June. The dominant catch during the study was dominated by scad fish (Decapterus spp). The level of effectiveness of the dominant catch of purse sein fishermen is highest at a distance of 4-12 miles with a total catch of 1,070 kg of the total catch of 1,950 kg.

Seasonal Larval Abundance of the Blackfly, Simulium damnosum Complex and the Physico-chemical Properties of their Breeding Sites in Oji River System, Enugu State, Nigeria

Seasonal larval abundance of the blackfly, Simulium damnosum complex, and the physico-chemical properties of their breeding sites in Oji river system was carried out, with the aim of finding out the season that promotes the breeding of S. damnosum complex and the effect of the physico-chemical properties of the breeding sites of S. damnosum complex on larval abundance. Larvae of S. damnosum complex were collected monthly from forty-eight (48) breeding sites in four sampling units for three years, in dry and wet seasons. The physico-chemical properties of the breeding sites of S. damnosum complex studied were copper, dissolved oxygen, magnesium, nitrate, pH, phosphate, potassium, temperature, and water velocity. A total of six hundred and ninety one (691) larvae of S. damnosum complex were collected in the Oji river system in both seasons. Wet season catch was more and comprised 82% of the total catch, while dry season catch comprised 18% of the total catch. Dry and wet seasons catches in the sampling units were found to differ statistically. All the physico-chemical properties of the breeding sites of S. damnosum complex determined showed positive correlations with total larval abundance in both seasons, except copper which showed no correlation with total larval abundance in the dry season. Wet season promotes larval abundance of S. damnosum complex, and the physico-chemical properties of the breeding sites of S. damnosum complex play some roles (in varying degrees) in larval development.

PEMANFAATAN ALAT BANTU RUMPON ELEKTRONIK TERHADAP PENINGKATAN HASIL TANGKAPAN PADA ALAT TANGKAP GILL NET DI WILAYAH PESISIR KAB. BULUKUMBA

The purpose of this study was to determine the yield and type of catch, the comparison of the number of catches and the efforts to manage electronic FADs on Gill Net fishing gear. This research was conducted in Bulukumba waters from February to March 2017. Data collection was carried out by direct observation of fishermen in Bulukumba waters. The samples used in this study were FADs installed by fishermen in the waters of Bulukumba as many as 20 locations. Based on the research results, fish catches with electronic FADs ranged from 98 to 131 fish per fishing trip with a total catch of 2,324 fish. Meanwhile, the usual FAD catches ranged from 51 to 84 fish per fishing trip with a total catch of 1,313 fish and the highest type of fish was selar, followed by male mackerel, Selar bentong, white Kuwe, Layang, Barracuda, selangat and Mata goyang. The ratio between the catch and the use of electronic FADs was 64%, while the regular FADs were 36%. Considering that FADs are an effective tool in collecting fish, a sustainable management strategy is needed, including by (1) community based management, (2) limiting fishing efforts, (3) stopping the addition of shallow marine FADs. , (4) use of fishing gear with large mesh sizes and (5) prioritize the use of deep sea FADs.