Environmental Drivers of Recruitment Variability in Narrow‐Barred Spanish Mackerel Scomberomorus commerson Lacépède, 1800

The growth of narrow-barred Spanish mackerel (Scomberomorus commerson) was examined over a broad spatial scale encompassing the east coast of Queensland, Australia. Our aim was to use back-calculation to identify potential biases in growth estimation, and to provide a more recent estimate of growth for Spanish mackerel on the east coast of Queensland. Growth trends were determined using the body proportional hypothesis (BPH) back-calculation model and compared between back-calculated and observed length-at-age data. The back-calculated von Bertalanffy growth function parameters estimated for males and females, respectively, were L8 = 1047 mm, K = 0.75, t0 = –0.18 and L8 = 1248 mm, K = 0.51 and t0 = –0.39. Significant differences in growth of Spanish mackerel sampled among different regions along the east coast were observed. A comparison of back-calculated and observed length-at-age data revealed significant biases in the observed length-at-age data for younger aged fish. Our findings contrast with previous estimates of growth for Spanish mackerel from the east coast of Queensland and highlight the use of back-calculation for the first few annuli as a means of avoiding biases in growth estimation arising from gear selectivity associated with fishery-dependent samples of fast-growing fish.

The role of uncertainty in fish stock assessment and management: A case study of the Spanish mackerel, Scomberomorus maculatus, in the US Gulf of Mexico

The lighter side of reference points

Narrow-barred Spanish mackerel (Scomberomorus commerson) is one of the high-value commercial fish species exported from the Riau Archipelago. To meet export standards, this species must fulfill specific quality criteria to be considered suitable for export. This study aims to analyze the fishing season pattern and size structure of catchable Spanish mackerel (Scomberomorus commerson) in the waters of the Riau Archipelago. Data were collected through field surveys, direct observation of catches, and analysis of gillnet vessel logbook records from 2018 to 2022. Fishing productivity was calculated using catch per unit effort (CPUE), and the seasonal pattern was identified using the Simple Moving Average (SMA) method and monthly fishing season index (Mt,b). The results showed that the fishing season for Spanish mackerel occurs from January to May, with the peak season in February. The size structure analysis revealed that 87.6% of the sampled fish were larger than 61 cm, indicating that they had reached first maturity (catchable size). Nevertheless, a portion of smaller fish was still caught, highlighting the need for improved management of fishing gear and fishing grounds to support resource sustainability. These findings, once implemented, are expected to significantly improve the sustainability of Spanish mackerel populations, offering hope for the future of this species. These findings are expected to contribute to the implementation of precision fisheries management in Fisheries Management Area (FMA) 711. Key words: catchable size, catch per uni effort, fishing season pattern, precision fisheries, Spanish mackerel

Pati regency is a coastal area that contributes significantly to Indonesia’s fisheries sector. One if its major fishing ports, PPP Bajomulyo, serves as a hub for fishing activities, with catches ranging from small to large pelagic fish, including Spanish mackerel (Scomberomorus commerson). This study aims to examine to relationship between oceanographic parameters and Spanish mackerel catch volumes at PPP Bajomulyo over the 2021-2023 period. A survey-based approach incorporating satellite image overlay was employed. The analysis of non-linier relationships between variables was conducted using Generalized Additive Model (GAM), implemented in RStudio. Satellite image processing was performed using SeaDAS, while spatial analysis was carried out in ArcGIS. The findings reveal that the interaction between sea surface temperature (SST) and chlorophyll-a concentrations accounted for 11,44% oof catch variability. Elevated SST above 29,5 °C were associated with increased catch rates, whereas extreme temperature (>35 °C or <28 °C) corresponded with significant declines. Chlorophyll-a exerted a relativity weak influence on catch, suggesting that although it serves as a proxy for primary productivity, Spanish mackerel distribution is more strongly governed by thermal conditions and prey availability. The study further identified that optimal fishing grounds were predominantly located in northern Central Java waters, particularly during seasons characterized by favorable oceanographic conditions.

The Scombridae fish group belongs to the type of pelagic fish that is most frequently caught in Indo-Pacific waters, including the Indonesian archipelago, and has a relatively high economic value. In Singkawang City, the catch of Scombridae species such as mackerel tuna, narrow-barred Spanish mackerel, and short mackerel has shown considerable fluctuations in both price and catch volume. Therefore, the purpose of this study is to analyze the fluctuations in catch volume and prices of Scombridae fish, namely large Spanish mackerel, narrow-barred Spanish mackerel, frigate tuna, eastern little tuna, and short mackerel. The data used in this study are secondary data obtained from https://portaldata.kkp.go.id/portals/data-statistik/layer1. From this website, the data collected include fish catch volumes and prices for the period of 2019–2023. The results show that the fish with the highest price was the narrow-barred Spanish mackerel, which reached IDR 60,000 per kg in 2021, and even its lowest price was still higher than other Scombridae species, at IDR 45,000 per kg. Meanwhile, the lowest price among the five observed Scombridae species was recorded for short mackerel at IDR 15,000 per kg. Regarding catch volume, narrow-barred Spanish mackerel, eastern little tuna, and short mackerel were recorded throughout the 2019–2023 period.

The choice of fishing gear and catching strategy should be taken into consideration in the management of fish stocks. Here, paired fishing trials in a pelagic recreational fishery compared the catch composition, catch rate and size selectivity between handline and trolling fishing methods in Iranian coastal waters of the Gulf of Oman. Total catch rate was 1.06 fish hr–1 vs 0.88 fish hr–1 for handline and trolling, respectively, a 17% difference which was significant (p < 0.05). Generally, the handline method captured more fish than trolling for most species, but size selectivity tended to be species-specific per gear type. The handline fishing method captured larger talang queenfish (Scomberoides commersonnianus), while trolling captured larger narrow-barred Spanish mackerel (Scomberomorus commerson), pickhandle barracuda (Sphyraena jello) and Indian threadfish (Alectis indicus). Technical measures, such as gear restrictions, could be applied to recreational pelagic fisheries management in the Gulf of Oman. Such measures could improve species-specific exploitation patterns.

The human influence on marine ecosystems is being recognized as a basis for extending the horizons of management. Historical anthropogenic influence has involved a wide variety of factors, including the effects of fishing on the dynamics of individual resource species. More inclusive complexity includes the interactions among species, and their interactions with other aspects of their biotic and physical environment. In this chapter, we review these elements of complexity for the central Baltic Sea. This ecosystem has a long history of human influence and its own special characteristics, due to its geographic location, geomorphic traits, and socio-political context. More and more of the complexity of this ecosystem is being recognized as scientists add to the wealth of documentation regarding the influence of surrounding terrestrial activities, monitor the dynamics of component populations, establish the effects of weather and climate, and illuminate the relationships among the various elements of the ecosystem. There is a great deal of historical information to characterize the changes that have occurred, not only among the various species making up the ecosystem, but also at the ecosystem level. Some of these have involved regime shifts, in part owing to climatic factors. Such significant changes involve more than one of the ecosystem's trophic levels as well as physical features such as salinity, temperature, and oxygen concentration. We begin to understand some of the complexity of ecosystems when we recognize that such factors are not alone, however, and realize that trophic cascade dynamics and feedback loops are also involved.

Fish species and processing methods could affect the volatile flavour composition and amino acid profile of fishery commodity. The objectives of this study were to identify volatile components and amino acid profile of two considered predominant fish species in Indonesia which are freshwater Patin catfish (Pangasius hypophthalmus) and marine water fish, Spanish mackerel (Scomberomorus commerson). The methods used in this study were to detect volatile compounds using Gas Chromatography/Mass Spectrometry (GC/MS) on fresh and steamed of both species samples (100°C for 30 minutes) and amino acid profile were also analyzed using High Performance Liquid Chromatography (HPLC). The volatile components analysis successfully detects as much as 29 and 59 volatiles compounds in fresh and steamed Patin catfish respectively, while 37 and 102 compounds were detected in fresh and steamed Spanish mackerel samples. Most of detected components derives from hydrocarbons, aldehydes, alcohols and ketone groups which could affected by their chemical composition and resulted from various thermal involved reaction. The amino acids profile identification results showed that glutamic acid was found higher compared to other amino acids standards in both samples. Glutamic acid is non-essential amino acid which is important in umami taste substances.

Irradiation and Postirradiation Storage at 2 ± 2°C of Tilapia (Tilapia nilotica × T. aurea) and Spanish Mackerel (Scomberomorus commerson): Sensory and Microbial Assessment

Estimates of genetic effective population size (Ne) using molecular markers are a potentially useful tool for the management of endangered through to commercial species. However, pitfalls are predicted when the effective size is large because estimates require large numbers of samples from wild populations for statistical validity. Our simulations showed that linkage disequilibrium estimates of Ne up to 10,000 with finite confidence limits can be achieved with sample sizes of approximately 5000. This number was deduced from empirical allele frequencies of seven polymorphic microsatellite loci in a commercially harvested fisheries species, the narrow-barred Spanish mackerel (Scomberomorus commerson). As expected, the smallest SD of Ne estimates occurred when low-frequency alleles were excluded. Additional simulations indicated that the linkage disequilibrium method was sensitive to small numbers of genotypes from cryptic species or conspecific immigrants. A correspondence analysis algorithm was developed to detect and remove outlier genotypes that could possibly be inadvertently sampled from cryptic species or nonbreeding immigrants from genetically separate populations. Simulations demonstrated the value of this approach in Spanish mackerel data. When putative immigrants were removed from the empirical data, 95% of the Ne estimates from jacknife resampling were greater than 24,000.

Commercial or recreational fishing may be associated with a wide range of potentially lethal events. We report the case of a 56-year-old man who died of blunt force chest and abdominal trauma after impact with a large Spanish mackerel (Scomberomorus commerson) that had jumped into his recreational fishing boat. Injuries at autopsy included soft tissue bruising with fractured ribs, a ruptured diaphragm, intestinal and mesenteric contusions, contusion and disruption of the pancreas, and hilar splenic lacerations with a left-sided hemothorax and a hematoperitoneum. The clear temporal association of pain and progressive deterioration leading to cardiac arrest after the impact indicated that lethal injuries had been sustained. A variety of fish and cetacean species are known to jump out of the water sometimes to escape predators. It was reported that a large number of jumping fish being pursued by sharks were observed in the harbor on the day of the reported incident. This case demonstrates that lethal blunt abdominothoracic trauma may be caused by impact with Spanish mackerel, increasing the range of potentially dangerous situations that may be encountered while fishing.

Qualitative and quantitative assessment of the presence of ciguatoxin, P-CTX-1B, in Spanish Mackerel (Scomberomorus commerson) from waters in New South Wales (Australia)

Consumption of marine fishes with high histamine levels due to improper storing leads to cause scombroid or histamine fish poisoning. In spoiled fishes, bacteria begin to break down the histidine into histamine by decarboxylation activity. Previous studies reported that black muscle fishes usually produce large amounts of histamine-producing bacteria (HPB). In this study, two white muscle fishes such as Scomberomorus commerson (Narrow-barred Spanish mackerel) and Nemipterus japonicus (Japanese threadfin bream) were chosen to detect the presence of histamine-producing bacteria (HPB). The fish samples were purchased from Ukkadam fish market in Coimbatore and examined for the occurrence of HPB on Niven agar. The isolated HPB on media were analyzed for identification based on their morphological characteristics, primary test, and biochemical test. Finally, 8 colonies were confirmed as the cause for histamine production of both fishes and among them, 5 belong to the family Enterobacteriaceae and others belong to the family Aeromonadaceae, Morganellaceae, and Enterococcaceae. Our study showed that the histamine-producing bacteria highly reported in dark-muscle fishes were also isolated from the chosen white-muscle fishes. Hence the presence of HPB indicates the improper maintenance of fish in retail fish markets. This considerable incidence of histamine-producing bacteria which on proliferation under suitable conditions may contribute to toxic histamine accumulation in the flesh of fishes.

A review on fishing gear in China: Selectivity and application