Gonad Size Research Articles

Evaluating the gonads of left-handed children using ultrasonography and comparing the findings with those of right-handed ones.

Lateralization affected gonad size in girls. In boys, gonads were not affected by lateralization. Cerebral lateralization may affect the hypothalamic-pituitary-gonadal axis in girls. • Hand use varies according to which cerebral hemisphere is dominant. Males tend to be more left-handed than females. Brain asymmetry can affect the neuroendocrine axis. • Ultrasonographic gonadal dimensions were examined in left-handed and right-handed children. Cerebral lateralization may affect the hypothalamic-pituitary-gonadal axis in girls.

Effects of Vitamin C on the Gonad Growth, Texture Traits, Collagen Content and Synthesis Related Gene Expression of Sea Urchin (Mesocentrotus nudus).

The market value of sea urchin gonads is determined by the specific characteristics associated with gonad size and texture. Formulated feeds can effectively promote the gonad growth of sea urchins but cannot assure essential gonad texture traits. The objective of this study was to investigate the impact of vitamin C (VC) on the gonad growth, texture, collagen content, and the expression of genes involved in the collagen synthesis of sea urchins (Mesocentrotus nudus). Graded amounts of VC (0, 3000 and 6000 mg/kg) were supplemented to make three formulated feeds. Fresh kelp (Saccharina japonica) was used as the control diet. Each diet was randomly distributed to three tanks of M. nudus. The results indicated that the gonadosomatic index (GSI) and texture traits of M. nudus fed C3000 were significantly greater than those fed C0 and C6000. Collagen type I (Col I) in the gonads of M. nudus fed C3000 showed significantly greater areas than those fed C0 and C6000. Consistently, the expression levels of collagen alpha-1 (colp1α) of M. nudus fed C3000 were significantly higher than those fed C0 and C6000. As for the transforming growth factor beta (tgf-β)/Smads pathway, the expression levels of collagen synthesis genes (tgf-β receptor 1 and 2, smad nuclear-interacting protein 1 (snip1) and prolyl 4-hydroxylase subunit beta (p4hβ)) in the C3000 group were significantly greater than those in the C0, C6000 and kelp groups. On the contrary, the expression levels of collagen degradation genes (lysyl oxidase-like 2 (loxl2) and matrix metalloproteinase 14 (mmp14)) in the C3000 group were significantly lower than those in the C0, C6000 and kelp groups. In conclusion, VC at an addition level of 3000 mg/kg significantly increased the gonad texture and collagen contents of M. nudus, which could be accomplished by increasing collagen synthesis and inhibiting collagen degradation through the tgf-β/Smads pathway. These results could contribute to better understanding the beneficial effects of VC addition on the gonad texture quality of M. nudus.

Effect of parasite infection and invasion history on feeding, growth, and energy allocation of cane toads

Abstract The energy allocation decisions that organisms make can differ between sexes and populations and can be influenced by factors such as age and parasite infection. We conducted experimental parasite infections on common-garden reared cane toads originating from sites across the species’ invasive range in Australia to assess how sex, parasite infection, and invasion history affected the toad’s food intake, growth rate, and organ weights. Female toads had larger fat stores, larger livers, and larger gonads than did males, reflecting increased investment into gametes. Growth rate did not differ between the sexes. Lungworm infection increased feeding by male but not female toads and increased fat storage in all toads. Fat body, liver, gonad sizes, and feeding rates all differed among toads from different locations within the toad’s invasion transect across Australia, even though our measurements were made under standardized conditions on captive animals. Toads from populations close to the invasion front ate more, had heavier fat bodies, and had larger livers than did toads from long-colonized areas, but they had smaller gonads. This pattern reflects the evolution of a more dispersive phenotype among invasive populations, whereby the rate of dispersal is enhanced by increased energy intake and storage, and delayed reproduction.

Effect of basket height and stocking density on production of the sea urchin Tripneustes gratilla: insights and recommendations

Basket height and stocking density are crucial and related factors for successful commercial sea urchin aquaculture, but these factors have not been definitively determined for production of Tripneustes gratilla. This study investigated the effects of varying basket heights (deep 30 cm vs. shallow 15 cm) and stocking densities (4, 6 and 8 kg.m−2 or 13, 19 and 24% coverage of available basket surface area) on aquacultural production of T. gratilla. Contrary to previous suggestions, reduced consumption was identified as the cause of decreased production in deeper baskets. Consumption was significantly higher in shallow baskets than deep baskets for both the fresh seaweed, Ulva lacinulata, (W = 38, p = 0.026) and formulated feed (W = 76.5, p = 0.007). Consequently, baskets of approximately 15 cm deep are recommended to enhance production of T. gratilla and possibly other urchin species. Two subsequent trials assessed production of T. gratilla at different stocking densities. Trial 1 aimed to maximize urchin size over a three-month grow-out period using fresh U. lacinulata, while trial 2 focused on enhancing gonad production over two months using formulated feed. Although greater stocking density significantly reduced the specific growth rates of individual urchin mass in both trials (p < 0.044), there was no significant impact on mortality, net production or gonad size and quality. The variations in growth rates were attributed to spine loss resulting from negative behavioural interactions (F2, 9 = 9.551; p = 0.005). Based on the objectives of both grow-out and gonad-enhancement phases, we recommend a stocking density of approximately 20% coverage.

Post-mortem examinations of New Zealand birds. 3. Shining cuckoos (Chrysococcyx lucidus Aves: Cuculinae)

ABSTRACT I examined 107 shining cuckoos that died accidentally in the northern North Island, New Zealand, during 39 years. Birds arriving on migration in spring were all in adult plumage. Juveniles occurred mainly from January to March. The sex-ratio of adults was 1:1. In several measurements, females were slightly larger than males on average, and adults slightly larger than juveniles. Gonad size suggested readiness for breeding from September to January (inclusive). Ninety-one gizzards held a total of 3754 arthropod food items. Insects (10 orders) made up around 94% of items and just two orders accounted for 79% of food items: caterpillars (larval Lepidoptera, 55%) and beetles (Coleoptera, 24%). ‘Spiny’ caterpillars made up roughly 8% of total caterpillars. Ladybirds (Coccinellidae) made up 21% of beetles. Shining cuckoos ate small prey, mostly 1–10 mm long (44%) and 11–20 mm long (43%). By eating hairy caterpillars and ladybirds, shining cuckoos exert predatory control on insects that other birds avoid. By gorging (up to 258 insects per stomach) the cuckoo might dampen the impact of herbivorous insects (e.g. caterpillar infestations) on plants.

Photoperiodic response of a subtropical Passerine, the red-vented bulbul, Pycnonotus cafer stanfordi Deignan

: In the present study, photoperiodic response of red-vented bulbuls, Pycnonotus cafer stanfordi Deignan was studied at Lumami (26oN), Zunheboti district, Nagaland. In birds kept under natural lighting, testicular and follicular developments began in February (daylength 11.5 hr/day); gonads developed progressively through March-May period (12-13 hrs/day), peaked in June (13hr, 34min/day) and thereafter declined to reach smaller in size during September. Seasonal changes in the size and activity of gonads were abolished in birds transferred to fixed duration of 10L/14D during December (quiescent phase). Under constant 16L/8D and 20L/4D photoperiods, gonads developed almost at similar pace, peaked in 3 months of exposure and thereafter, regressed fully during next 3 months owing probably to the development of photorefractoriness. Absolute development of gonads was not significantly different in groups kept under natural lighting (13hr, 34min/day), 16L/ 8D and 20L/4D daylengths. Body mass cycles of birds kept under NDL, 16L/8D and 20L/4D were temporally similar to gonadal cycles. No significant change occurred in the body mass of birds exposed to constant 10L/14D. It may be suggested that some common mechanisms engender photoinduced changes in gonad and body mass of red-vented bulbuls and daylengths higher than what birds experience naturally are superfluous in impacting the neuroendocrine and metabolic mechanisms.

POPULATION DYNAMICS OF THE THREE-SPOT SWIMMING CRAB (PORTUNUS SANGUINOLENTUS) IN PATI WATERS, CENTRAL JAVA

Currently, Portunus sanguinolentus is one of the fishery commodities that has experienced a decline in population due to exploitation pressures and habitat or environmental damage. This has an impact on changes in the population structure and reproductive strategy of P. sanguinolentus, with parameters that can change, among others, the size of the first gonad becoming smaller, changes in spawning areas and seasons, and changes in the balance of the sex ratio. This study aims to determine the population dynamics of P. sanguinolentus in Pati Regency, Central Java, and whether it is useful for the processing industry to make a new product. Data and information were obtained through observation, interviews, and enumeration, which were carried out at each fish landing site. Collecting data from catches in fishing areas below 12 miles with a maximum depth of 15 m for 5 months. The FISAT II software was used to analyze the growth parameters, mortality rate, and exploitation rate. Obtained weight data of 7.72 kg with a total sample of 107 ind. Detailed data were obtained for 46 females with an average width of 106.24 mm and 61 males with a width of 103.95 mm, and the average weight of the entire sample was 74.26 g.

Design, Synthesis and Gene Modulation Insights into Pigments Derived from Tryptophan-Betaxanthin, Which Act against Tumor Development in Caenorhabditis elegans.

The use of betalains, which are nitrogenous plant pigments, by the food industry is widespread and reflects their safety after intake. The recent research showed outstanding results for L-tryptophan-betaxanthin, a phytochemical present in traditional Chinese medicine, as an antitumoral agent when the activity was evaluated in the animal model Caenorhabditis elegans. Thus, L-tryptophan-betaxanthin is now presented as a lead compound, from which eleven novel structurally related betaxanthins have been designed, biotechnologically produced, purified, and characterized. The antitumoral effect of the derived compounds was evaluated on the JK1466 tumoral strain of C. elegans. All the tested molecules significantly reduced the tumoral gonad sizes in a range between 31.4% and 43.0%. Among the novel compounds synthesized, tryptophan methyl ester-betaxanthin and tryptophan benzyl ester-betaxanthin, which are the first betalains to contain an ester group in their structures, caused tumor size reductions of 43.0% and 42.6%, respectively, after administration to the model animal. Since these were the two most effective molecules, their mechanism of action was investigated by microarray analysis. Differential gene expression analysis showed that tryptophan methyl ester-betaxanthin and tryptophan benzyl ester-betaxanthin were able to down-regulate the key genes of the mTOR pathway, such as daf-15 and rict-1.

Timing of puberty in F1-generation hatchery-produced greater amberjack (Seriola dumerili)

We evaluated the onset of puberty of first-generation (F1) hatchery-produced greater amberjack (Seriola dumerili) reared in sea cages for 5 years. Fish were sampled every year in June, at the expected peak of the spawning period in the Mediterranean Sea. No sexual dimorphism in body weight was observed in the study. The ovaries of 1 and 2-year-old (yo) females consisted of primary oocytes only, while at the age of 3-yo early vitellogenic (Vg) oocytes were also identified, but with extensive follicular atresia. At the age of 4-yo, late Vg oocytes were observed, but again extensive follicular atresia characterized the ovaries of 50 % of females. At the age of 5-yo, follicular atresia of Vg oocytes was very limited. In males, gametogenesis was evident already in 1- and 2-yo fish, and 100 % of sampled 3-yo males produced collectable viable sperm. Plasma testosterone (T), 17β-estradiol (E2), and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-P) remained similar in 3 – 5-yo females, with T and E2 levels being highest in females in advanced vitellogenesis or with significant follicular atresia, compared to immature females. In males, plasma T declined over the years, while 11-ketotestosterone (11-KT) and 17,20β-P were highest in 4 and 5-yo males, with spermatozoa motility characteristics being improved from the 4th year onwards. The administration of GnRHa implants to 5-yo fish induced only two spawns, albeit no fertilized eggs were obtained. The results indicate that hatchery-produced greater amberjack males mature well and within the same age observed in the wild, however with smaller gonad size. On the contrary, females mature later than in the wild, also with a smaller gonad size. Spawning in response to GnRHa treatment was not effective, suggesting that Mediterranean hatchery-produced broodstocks may be dysfunctional, and further research is needed to document any improvement as the fish get older, or to determine if the results may be related to the specific stock of fish.

Germline mitotic quiescence and cell death are induced in Caenorhabditis elegans by exposure to pathogenic Pseudomonas aeruginosa.

The impact of exposure to microbial pathogens on animal reproductive capacity and germline physiology is not well understood. The nematode Caenorhabditis elegans is a bacterivore that encounters pathogenic microbes in its natural environment. How pathogenic bacteria affect host reproductive capacity of C. elegans is not well understood. Here, we show that exposure of C. elegans hermaphrodites to the Gram-negative pathogen Pseudomonas aeruginosa causes a marked reduction in brood size with concomitant reduction in the number of nuclei in the germline and gonad size. We define 2 processes that are induced that contribute to the decrease in the number of germ cell nuclei. First, we observe that infection with P. aeruginosa leads to the induction of germ cell apoptosis. Second, we observe that this exposure induces mitotic quiescence in the proliferative zone of the C. elegans gonad. Importantly, these processes appear to be reversible; when animals are removed from the presence of P. aeruginosa, germ cell apoptosis is abated, germ cell nuclei numbers increase, and brood sizes recover. The reversible germline dynamics during exposure to P. aeruginosa may represent an adaptive response to improve survival of progeny and may serve to facilitate resource allocation that promotes survival during pathogen infection.

Growth patterns and reproductive aspect of Naleh (Barbonymus sp.) in Krueng Lanca, Nagan Raya Regency, Aceh Province

Naleh (Barbonymus sp.) is one species of native fish found in Aceh Waters. This study examines the growth patterns and reproductive aspects of the fish in Krueng Lanca of Nagan Raya, Aceh Province. The study lasted five months (January - May 2022). Sampling was carried out purposively, once a month, on five different stations using gill nets (mesh size: 0.5 inches, 1.0 inches, and 1.5 inches and cast nets (D: 6 meters, mesh size: 0.5 inches). A total of 171 Naleh was caught in these waters. The calculation results obtained a length-weight relationship W = 0,0003*L2.2234 (r2 = 0.8823) for males, which shows the nature of allometric and W = 6E-06*L3.0684 (r2 = 0.8566) for females which shows the isometric. The sex ratio of Naleh in these waters was 1.1: 1. The size of the first mature gonads was 60-69 mm (males) and 90-99 mm (females) with a Gonadosomatic Index of 1.92-3.04 % (Males) and 8.73-11.61 % (females). The peak of the Naleh spawning season in Krueng Lanca waters was thought to occur from March to April, with the number of eggs ranging from 1,853-3,813 and a diameter of 1.18-1.43 mm. Based on the oocyte distribution, the peak of spawning of the fish was categorized as multiple spawners.

Orange mud crab (Scylla olivacea) exploitation at Sorong waters

Mangrove forests along the vast coast of West Papua serve as the habitat for mud crabs, which are high-value economic resources marketed to various regions in Indonesia. However, intensive utilization impacts the sustainability of mangrove crab populations, especially orange mud crabs (Scylla olivacea). Exploitation studies need to be conducted for further use to manage crab resources. This study was conducted for six months, from April to September 2021, with a sample of 2,971 orange mud crabs. Data analysis was carried out using crab carapace width (CW) data to predict resource exploitation and sustainability. The caught orange mud crab size was 80-190 mm, with natural mortality (M) lower than fishing mortality (F). The exploitation of this crab has attained E = 0.72, which proves that overfishing. We can do the management of orange mud crabs by observing the size of mature gonads and spawning areas to provide an opportunity to increase the population in the waters.

Thermal Effects on Ecological Traits of Salmonids

Here, I review thermal influences on metabolic rates and aerobic scope; growth; adult body size; and reproductive and behavioural traits, such as tendency and timing of the migration of salmonid fishes. A thermal window bounded by the upper and lower incipient lethal temperatures (UILT and LILT) determines where salmonids can survive. For most salmonids, LILT is close to 0 and UILT is between 20 and 30 °C. UILT and LILT are influenced by the acclimation temperature. Thermal tolerance is affected by fish size and ambient oxygen content, which decreases with increasing temperature. Standard metabolic rate (SMR), the energy required to maintain essential functions, increases with temperature, whereas maximum metabolic rate (MMR) increases with temperature until reaching a peak (pejus). Then, it decreases gradually to zero, i.e., the upper critical limit (TCrit). Aerobic scope (AS = MMR-SMR) reaches its maximum at the pejus temperature. Metabolic rates and aerobic scope can be modified by temperatures that the fish experiences during embryogenesis and possibly also as larvae and young fry. At maximum feeding, maximum growth increases to a point at or below the pejus temperature. The optimum temperature for growth decreases with reduced food intake and increased body size. As for metabolic rate, the growth rate is influenced by the temperature during embryonic development. In a warmer climate, adult body size is expected to decrease chiefly because of a younger age at maturity. Parental fish retained at a higher temperature during maturation produce larger eggs, and this change in egg size may also be transferred to next-generation offspring. Furthermore, embryogenesis in warmer water leads to larger gonad and egg sizes at maturity. Water temperature influences locomotion, foraging and migratory activity. In a warmer climate, juveniles migrate to the sea earlier in spring. In addition, higher embryo temperature leads to delayed return of adult salmon from the ocean. Thus, temperature affects life history traits of salmonid fishes, partly as a direct effect on metabolic rates and food consumption and partly induced as a phenotypically plastic effect. The phenotypically plastic response may preadapt offspring to perform better in the expected future thermal environment.

Reproductive Biology of Pterocaesio tile (Cuvier, 1830) in Supporting Responsible Fisheries Encircling Gillnet

Pterocaesio tile are generally caught by encircling gill nets using the schooling behavior of these species. The purpose of this study was analyze the biological reproduction of P. tile which induced sex ratio, gonadal maturity level, gonadal maturity index and size at first maturity. Data collection was carried out from October to December 2022. The data collection method was conducted using experimental fishing methods by operating unit gill net with mesh size of 1,75 and 2,0 inch. Fish samples of each actual fishing were measured total length and weight, dissected to determine sex, measured gonad weight and determined the level of gonadal maturity. The results showed that the sex ratio of male fish was higher than female fish. The GML phase is in phases I-V where the immature gonads are more dominant than the mature gonads, the GSI increases as GML increases. The size at first maturity for males is 20.6 cm and 18.6 cm for females.

Maturation, scale of gonad maturation stages and reproductive cycle of Pacific saffron cod Eleginus gracilis, Tilesius (Gadiformes, Gadidae)

Gonad size and weight dynamics and gonad-somatic index in the course of maturation have been analyzed, size structure and condition of oocytes of Pacific saffron cod at different stages of ovary matura- tion has been clarified. Reproductive cycle has been demonstrated, and scale of gonad maturation stages has provided.

Reproductive biology of mangrove clams Geloina expansa (Mousson, 1849) from mangrove at Kendari Bay, Southeast Sulawesi, Indonesia

ABSTRACT Mangrove clams are found in the soft substrates of the mangrove forest, where they reproductively adjust to the conditions in the aquatic environment. This study aimed to determine the reproductive biology pattern, such as sex ratio, gonad maturity level, gonadosomatic index, fecundity and size of the first maturity of mangrove clams. The samples included 80 ind./month collected manually from the mangrove ecosystem for one year. The reproductive biology patterns were calculated using standard formulas, each analysed using the χ2 test, semi-quantitative descriptive evaluation and non-linear regression. The results showed that more males than females were collected, accounting for 80.0–96.5% and 3.4–20.0%, respectively. Furthermore, both sexes’ gonad maturity developments coincided. The mangrove clam’s mature gonads are discoverable all year by observing the gonadosomatic index IV and spawning monthly occurrence. Their maturity peaked (levels III and IV) in February–April, indicated by a high index value ranging from 3.9–18.2 and 4.3–21.9 for the male and female mangrove shells, respectively. The male clams also had smaller sizes at maturity than females at 3.0 and 5.2 cm lengths, respectively. The food (organic sediment) availability was an essential environmental parameter in developing gonadal maturity.

In sea trout, the physiological response to salmon louse is stronger in female than in males.

The aims of this study were to compare male and female sea trout (Salmo trutta) with respect to their hypo-osmoregulatory ability over a simulated migration to seawater and their clinical and physiological response to salmon louse (Lepeophtheirus salmonis) infection in seawater and over a simulated pre-mature return to freshwater. For this purpose, 2-year-old hatchery-reared male and female brown trout (F1 offspring of wild caught anadromous fish) were infected with salmon lice and measured for changes in plasma ions, glucose, lactate and osmolality and relative heart, liver and gonad sizes during a simulated seawater migration and thereafter a premature return to freshwater after 4weeks in seawater (pre-adult louse). Un-infected trout served as control. Male trout used longer time to develop full hypo-osmoregulatory ability in seawater and showed a stronger response in plasma glucose and lactate following simulated premature return to freshwater, compared to female trout. Response to salmon louse was stronger in female trout, shown by stronger osmotic stress by chalimus (plasma Cl-) and pre-adult louse (plasma osmolality) and elevated relative liver size (hepatosomatic index) by pre-adult louse in female compared to male trout. Moreover, high plasma cortisol in infected female and low plasma cortisol in infected male trout produced a significant treatment-sex interaction on plasma cortisol. Lice infection intensity was initially higher in male (0.18 lice g-1) compared to female trout (0.11 lice g-1) at the chalimus stage, but equal between sexes at the pre-adult stage (male 0.15 and female 0.17 lice g-1). This study showed that female trout were better adapted for changes in water salinity, while male trout were more robust against salmon louse infection. These results suggests that the elevated salmon louse infection pressure generated by salmon farming have strong and unexplored negative effects on wild sea trout populations. Further research on this topic is vital for the conservation of wild sea trout populations.

Reproductive biology of Indian mackerel, Rastrelliger kanagurta (Cuvier, 1816) in the southern waters of West Java (FMA 573)

Indian mackerel is a small pelagic fish with important economic value in Java Island. This study aims to analyze the reproductive characteristics and determine management recommendations for the Indian mackerel in the southern waters of West Java. Fish monthly sampling collection was conducted at three fish landing ports: PPI Ciwaru, PPN Palabuhanratu, and PPI Binuangeun from July to December 2022. A total of 1,038 fish samples, comprised of 582 males and 456 females, were examined. The sex ratio was unbalanced, with a value of 1:0.79. Gonadosomatic indexes ranged from 0.19-0.95 and 0.45-3.41 for males and females, respectively. The fish fecundity ranged from 27,027 to 87,837 eggs. The Indian mackerel is predicted to spawn every month, with a peak season in August, and performs a total spawner pattern. The Indian mackerel reached the size of the first maturity gonad at 198.5 mm and 197 mm for males and females, respectively. Management strategies for Indian mackerel in the southern waters of West Java include setting the catch size above the first mature gonad size (197 mm), the mesh size of gillnets above 1.5 inches, and limiting fishing activities during the spawning season (July, August, and September).

Nonlethal Tools to Identify Mass Ovarian Follicular Atresia in Burbot

AbstractSkipped spawning, or variation in spawning periodicity, occurs in many annual spawning fish species and is an important consideration for population management. We assessed plasma sex steroid concentrations and measured gonad size and ovarian follicle diameter as metrics to nonlethally identify mass ovarian follicular atresia, which may contribute to skipped spawning in Burbot Lota lota. We maintained wild fish in captivity and exposed them to increasing water temperatures during a 3-wk period before the spawning season to induce mass ovarian follicular atresia. We collected ovarian follicles, blood plasma, and gonadal sonograms from fish weekly between January 28, 2018, and March 25, 2018. We histologically analyzed ovarian follicles to confirm stage of maturity. We measured concentrations of plasma sex steroids testosterone (T) and estradiol-17β (E2) by radioimmunoassay. We measured gonad diameter and circumference by ultrasonography and ovarian follicle diameter by image analysis. Mean plasma T concentration decreased from 8.94 ng/mL during late vitellogenesis to 1.83 ng/mL during atresia, suggesting that plasma T concentrations may be used to identify mass ovarian follicular atresia. We do not recommend using plasma E2 concentrations to identify mass ovarian follicular atresia because E2 concentrations rapidly decreased during the completion of vitellogenesis and the initiation of atresia in Burbot; therefore, plasma E2 may not accurately identify mass ovarian follicular atresia. Mean gonad diameter measured by ultrasonography decreased from 4.05 cm during late vitellogenesis to 3.65 cm during atresia. Mean diameter of ovarian follicles decreased during the final week of the study, suggesting that ovarian follicle diameter may be used to identify advanced mass ovarian follicular atresia. The nonlethal tools assessed—plasma sex steroid concentrations, ultrasonography, and ovarian follicle diameter—enable fisheries biologists to determine the occurrence and frequency of mass ovarian follicular atresia among Burbot in Lake Roosevelt and may be applied to other Burbot populations.

Environmental Friendliness Analysis of Purse Seine Operated by Km Sumber Baru, Belawan, North Sumatera

Purse Seine fishing gear is a fishing gear operated by several fishermen in the WPP NRI 571. Purse seine is a type of fishing gear that classified as surrounding nets, which is an active fishing gear to catch pelagic fish which who generally live in groups in large flocks. The main catch is Mackerel scad (Decapterus spp). The purpose of this study was to determine the level of environmental friendliness of the Purse seine fishing gear in PPS Belawan. The method used in this study is by using a score based on the Code of Conduct for Responsible Fisheries (CCRF) criteria, fish physiology analysis, and also analyze the suitability of fishing gear with the regulation of Permen KP.71 of 2016. Based on the results of the study, it can be concluded that physiologically fish include into fish fit for catching with a total length ranging from 19-24 cm, the average size of the first caught (Lc) at a length of 15 cmFL, the size of the first sentence gonads (Lm) 19.6 cmFL, Km. Sumber Baru does not meet the Regulations of the size of the vessel, and the Purse Seine fishing gear is very environmentally friendly with a score of 32 points.This Lc value is smaller than the Lm value. From this result, it is known that most of the scads caught have not passed the first gonadal maturity size (Lc&lt;Lm), but in terms of the specifications of the fishing gear, they have adjusted to the applicable regulations