Black Rockfish Research Articles

Dissecting the dynamic cellular transcriptional atlas of adult teleost testis development throughout the annual reproductive cycle.

Teleost testis development during the annual cycle involves dramatic changes in cellular compositions and molecular events. In this study, the testicular cells derived from adult black rockfish at distinct stages - regressed, regenerating and differentiating - were meticulously dissected via single-cell transcriptome sequencing. A continuous developmental trajectory of spermatogenic cells, from spermatogonia to spermatids, was delineated, elucidating the molecular events involved in spermatogenesis. Subsequently, the dynamic regulation of gene expression associated with spermatogonia proliferation and differentiation was observed across spermatogonia subgroups and developmental stages. A bioenergetic transition from glycolysis to mitochondrial respiration of spermatogonia during the annual developmental cycle was demonstrated, and a deeper level of heterogeneity and molecular characteristics was revealed by re-clustering analysis. Additionally, the developmental trajectory of Sertoli cells was delineated, alongside the divergence of Leydig cells and macrophages. Moreover, the interaction network between testicular micro-environment somatic cells and spermatogenic cells was established. Overall, our study provides detailed information on both germ and somatic cells within teleost testes during the annual reproductive cycle, which lays the foundation for spermatogenesis regulation and germplasm preservation of endangered species.

Transcriptomic analysis of the response mechanisms of black rockfish (Sebastes schlegelii) under noise stress from offshore wind farms

During the operational phase of offshore wind farms, the generation of low-frequency underwater noise has received widespread attention due to its potential adverse impact on fish health. This study conducted a field survey of underwater noise at offshore wind farms located in Shandong province, China. Subsequently, a small-scale experiment was conducted to study the stress on black rockfish (Sebastes schlegelii). The fish were exposed to noise with dominant frequency of 80 Hz, 125 Hz and 250 Hz. These frequencies are same with the frequencies from wind power noise (wpn) at the actual site. After a 40-day experimental period, transcriptome sequencing was conducted on brain, liver, and kidney tissues of black rockfish to elucidate the underlying molecular mechanisms involved in the response to noise stress originating from offshore wind farms. The results revealed that the 125 Hz group exhibited the highest number of differentially expressed genes (DEGs) between the noise-exposed and control check group (CK group), with a total of 797 in the brain, 1076 in the liver, and 2468 in the kidney. Gene Ontology (GO) analysis showed that DEGs were significantly enriched in entries related to cellular processes, membrane components, binding, and metabolism. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs were enriched mainly in metabolism, immunity, apoptosis, signal transduction, and diseases. The findings indicate that prolonged exposure to underwater noise from offshore wind farms may induce metabolic imbalance, immune dysfunction, and an increased risk of myocardial diseases in black rockfish.

Hemopexin regulates acute-phase inflammatory response against pathogenetic infections in black rockfish (Sebastes schlegelii)

Hemopexin as an acute-phase protein binds heme with a high affinity and participates in a variety of processes of physiology and pathology. Hemopexin plays an important role in regulating inflammatory response by regulating pro-/anti-inflammatory cytokines. In this study, the hemopexin gene was identified from black rockfish. The open reading frame of the black rockfish hemopexin (SsHPX) gene was predicted and amplified. The different expression patterns of SsHPX in microbial-challenged tissues and peripheral blood leukocytes (PBLs) were analyzed by RT-qPCR. The results indicated that SsHPX showed high evolutionary conservations in sequence and structure. The expression of SsHPX was significantly induced in a time-dependent manner in black rockfish intestine after Edwardsiella piscicida infection, while the evidently down-regulations were observed in the PBLs following the stimulations of two microbial ligands. The recombinant SsHPX protein (rSsHPX) exhibited microbial binding ability. In addition, rSsHPX could reduce bacterial proliferation with effect, thereby alleviating the inflammatory responses induced by bacteria. Moreover, almost all the expressions of pro-inflammatory cytokines (tnfα, il-1β, il-8 and il-17c) and anti-inflammatory cytokine (IL-10) were inhibited in black rockfish intestine cells stimulated by the mixing solution of LPS + rSsHPX comparing with the group with LPS stimulation. Overall, this study provides a theoretical basis for investigating the key roles of an acute-phase protein hemopexin in bacteriostatic ability and inflammatory regulations in black rockfish during bacterial infection. These findings also contribute to a better understanding of the relatively stable and conserved biological function of hemopexin during species evolution.

Relative Importance of Macroalgae and Phytoplankton to Nearshore Consumers and Growth Across Climatic Conditions in the Northern Gulf of Alaska

Macroalgae and phytoplankton support the base of highly productive nearshore ecosystems in cold-temperate regions. To better understand their relative importance to nearshore food webs, this study considered four regions in the northern Gulf of Alaska where three indicator consumers were collected, filter-feeding mussels (Mytilus trossulus), pelagic-feeding Black Rockfish (Sebastes melanops), and benthic-feeding Kelp Greenling (Hexagrammos decagrammus). The study objectives were to (1) estimate the proportional contributions of macroalgal and phytoplankton organic matter using carbon and nitrogen stable isotopes, (2) determine if macroalgal use affected consumer growth using annual growth rings in shells or otoliths, and (3) describe changes in organic matter use and growth during the Pacific Marine Heatwave (PMH; 2014–2016) in one consumer, mussels. Macroalgae were the major organic matter source (> 60%) to the diet for all three consumers. The relationships between macroalgal contribution and growth were neutral for both fish species and significantly positive for mussels. During the PMH, mussels had a drop (> 10%) in macroalgal contributions and grew 45% less than in other time periods. Simultaneously, the relationship between macroalgal contribution and mussel growth was strongest during the PMH, explaining 48% variation compared to 3–12% before or after the PMH. Collectively, the results suggest that macroalgae is likely more important to cold-temperate nearshore food webs than phytoplankton. Management actions aimed at conserving and expanding macroalgae are likely to benefit nearshore food webs under all climate scenarios and especially during marine heatwaves.

Effect of cytochrome c release on the mitochondrial-dependent apoptosis and quality deterioration of black rockfish (Sebastes schlegelii) postmortem storage

Apoptosis was associated with decreased sensory quality attributes of fish during postmortem storage. Based on cytochrome c (cyt-c) release plays a crucial role in apoptosis, the study aims to investigate the factors regulating cyt-c release and whether cyt-c acts as an endogenous pro-oxidant to trigger lipid oxidation. Within 12 h postmortem, dramatic changes in the intramuscular environment (glycogen from 1.57 mg/g to 0.65 mg/g; ATP reduced by 92.91%; pH value reaching the lowest (pH = 7.14)) and the mitochondrial environment (accumulation of mitochondrial ROS and Ca2+ levels) are induced mitochondrial swelling and opening of the MPTP (increased 34.35% and 31.91%), leading to the release of cyt-c from the mitochondria into the cytoplasm and the activation of caspase-3. This leads to lipid oxidation and degradation of myofibrillar proteins, accelerating quality deterioration in color and texture. The results suggest that cyt-c is involved in lipid oxidation during postmortem through the apoptotic mitochondrial pathway.

Effect of Dissolved Oxygen Concentration in High Water Temperatures Period on Survival Rate and Physiological Changes of Black Rockfish, Sebastes Schlegelii Reared Indoors

Effect of Dissolved Oxygen Concentration in High Water Temperatures Period on Survival Rate and Physiological Changes of Black Rockfish, Sebastes Schlegelii Reared Indoors

Effects of Yacon (Smallanthus sonchifolius) Juice Byproduct Administered Using Different Feeding Methods on the Growth Performance, Digestive Enzyme Activity, Antioxidant Status, and Disease Resistance against Streptococcus iniae of Juvenile Black Rockfish (Sebastes schlegelii)

This study was designed to evaluate the effects of yacon (Smallanthus sonchifolius) juice byproduct (YJB) on the growth performance, digestive and antioxidant enzyme activities, and disease resistance against Streptococcus iniae of juvenile black rockfish (Sebastes schlegelii) based on different feeding schedules. Four different YJB feeding strategies were evaluated: feeding the fish a basal diet continuously (control, T0), feeding them YJB (2.5 g/kg) continuously (T1), feeding them YJB for 1 day and the basal diet the next day (T2), and feeding them YJB for 1 day and the basal diet for the following 2 days (T3). No difference in survival among the treatments was found after the 8-week feeding trial (p > 0.05). However, the T1 and T2 groups exhibited significant enhancements in final body weight, weight gain, and specific growth rate compared with the T0 and T3 groups. Furthermore, the T1 and T2 groups showed a significant improvement in feed consumption, feed efficiency, and protein efficiency ratio compared with the T0 and T3 groups. No significant differences in the condition factor or viscerosomatic and hepatosomatic indices were observed among all the groups. Intestinal amylase, trypsin, and lipase activity was significantly (p < 0.05) higher in the T1 and T2 groups than in the T0 and T3 groups. Lysozyme, superoxide dismutase, and catalase activity along with glutathione peroxidase content were significantly (p < 0.05) higher under all YJB feeding regimens than those under the control treatment. The survival rates in all the YJB treatment groups after the S. iniae challenge were significantly (p < 0.05) enhanced. In conclusion, we recommend offering YJB at day-to-day intervals to improve growth performance, digestive enzyme activity, antioxidant status, and disease resistance against S. iniae.

Genome-wide identification, characterization, molecular evolution and expression profiling analysis of scavenger receptors in black rockfish (Sebastes schlegelii)

The scavenger receptors (SRs) gene family is considered as the membrane-associated pattern recognition receptors that plays important roles in the immune responses of organisms. However, there is currently limited research on the systematic identification of the SRs gene family in teleost and their role in the innate immunity of S. schegelii. In this study, we identified and annotated 15 SRs genes in S. schegelii. Through phylogenetic analysis, analysis of conserved domains, gene structure, and motif composition, we found that SRs gene family within different classes were relatively conserved. Additionally, we used qRT-PCR to analyze the expression patterns of SRs genes in immune-related tissues from healthy and Acinetobacter johnsonii-infected S. schegelii. The results showed that SRs genes exhibited different tissue expression patterns and the expression of SRs genes significantly changed after A. johnsonii infection. These results provided a valuable basis for further understanding of the functions of SRs in the innate immune response of S. schegelii.

Regulation of sperm motility by exosomes of ovarian fluid during female sperm storage in black rockfish (Sebastes schlegelii)

Sperm storage within the female reproductive tract is a widespread phenomenon among vertebrate species, including various viviparous teleosts. The black rockfish (Sebastes schlegelii) serves as a typical example, wherein sperm remains stored inside the ovary for extended periods, spanning over four months from entry until fertilization. While previous investigations have explored the occurrence of female sperm storage and its adaptive advantages, the precise mechanisms governing sperm storage in the ovary and the maintenance of sperm activity remain incompletely understood. Recently, extracellular vesicles or exosomes have been identified as important components of the oviductal or uterine fluid, but their interactions with sperm are not fully understood. Our study represented the isolation and identification of ovarian fluid exosomes (Ov-exos) from the black rockfish, while also affirming their role in sustaining sperm activity. Based on the transcriptome and proteome of the ovaries, it was found that the levels of gene transcription and protein translation, which related to exosomes, were upregulated compared to pre-mating levels, such as CD81, CD63, CD9, ANXA1, VPS25, and RAB8A. Furthermore, our study corroborated these findings through qRT-PCR analysis. Immunohistochemical localization of CD81 suggested that exosomes were secreted at the sperm storage site within the ovary. The ultrastructure of ovaries, particularly with exosomes, was examined by transmission electron microscopy (TEM). It was further found that epithelial cells and follicular layer cells secreted exosomes, which bound to the mid-piece of sperm stored in the ovaries. To validate our findings, experiments involving the co-incubation of sperm with Ov-exos were conducted. This analysis demonstrated that exosomes could bind with sperm and transfer their cargo, significantly enhancing sperm viability and motility. Notably, this study helps to reveal the complexity of sperm storage mechanisms and their adaptive implications in teleost reproduction.

Extracellular traps in skin lesions infected with lymphocystis disease virus in black rockfish (Sebastes schlegelii)

The lymphocystis disease (LCD), caused by Lymphocystis disease virus (LCDV), is a benign and self-limiting disease described in a many freshwater and marine fish species. Hypertrophic fibroblasts and extensive aggregation of inflammatory cells are characteristics of LCD. In the present study, small animal imaging and ultrastructural investigations were carried out on the lymphocystis nodules of black rockfish (Sebastes schlegelii) naturally infected with lymphocystis iridovirus, to assess pathology, and the exudate with particular attention to the formation of extracellular traps (ETs) in vivo. Ex vivo were examined by nodules sections and primary cells stimulation. By histopathological analysis, the nodules contained infiltrated inflammatory cells and extensive basophilic fibrillar filaments at the periphery of the hypertrophied fibroblasts. ETs were assessed in nodules samples using indirect immunofluorescence to detect DNA and myeloperoxidase. Moreover, LCDV was able to infect peritoneal cells of black rockfish in vitro and induce the formation of ETs within 4 h. In summary, this study proved that ETs are involved in the response to LCDV infection and may be involved in formation of lymphoid nodules. Taken together, the findings provide a new perspective to determine the impact factors on the growth of nodules.

C-type lectin 12B/4E of black rockfish (Sebastes schlegelii) macrophages as pattern recognition receptors in the antibacterial mechanism of exploration

As lower vertebrates, fish have both innate and adaptive immune systems, but the role of the adaptive immune system is limited, and the innate immune system plays an important role in the resistance to pathogen infection. C-type lectins (CLRs) are one of the major pattern recognition receptors (PRRs) of the innate immune system. CLRs can combine with pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs) to trigger NF-κB signaling pathway and exert immune efficacy. In this study, Ssclec12b and Ssclec4e of the C-type lectins, were found to be significantly up-regulated in the transcripts of Sebastes schlegelii macrophages stimulated by bacteria. The identification, expression and function of these lectins were studied. In addition, the recombinant proteins of the above two CLRs were obtained by prokaryotic expression. We found that rSsCLEC12B and rSsCLEC4E could bind to a variety of bacteria in a Ca2+-dependent manner, and promoted the agglutination of bacteria and blood cells. rSsCLEC12B and rSsCLEC4E assisted macrophages to recognize PAMPs and activate the NF-κB signaling pathway, thereby promoting the expression of inflammatory factors (TNF-α, IL-1β, IL-6, IL-8) and regulating the early immune inflammation of macrophages. These results suggested that SsCLEC12B and SsCLEC4E could serve as PRRs in S. schlegelii macrophages to recognize pathogens and participate in the host antimicrobial immune process, and provided a valuable reference for the study of CLRs involved in fish innate immunity.

Molecular and Physiological Effects of 17α-methyltestosterone on Sex Differentiation of Black Rockfish, Sebastes schlegelii.

It is widely known that all-female fish production holds economic value for aquaculture. Sebastes schlegelii, a preeminent economic species, exhibits a sex dimorphism, with females surpassing males in growth. In this regard, achieving all-female black rockfish production could significantly enhance breeding profitability. In this study, we utilized the widely used male sex-regulating hormone, 17α-methyltestosterone (MT) at three different concentrations (20, 40, and 60 ppm), to produce pseudomales of S. schlegelii for subsequent all-female offspring breeding. Long-term MT administration severely inhibits the growth of S. schlegelii, while short term had no significant impact. Histological analysis confirmed sex reversal at all MT concentrations; however, both medium and higher MT concentrations impaired testis development. MT also influenced sex steroid hormone levels in pseudomales, suppressing E2 while increasing T and 11-KT levels. In addition, a transcriptome analysis revealed that MT down-regulated ovarian-related genes (cyp19a1a and foxl2) while up-regulating male-related genes (amh) in pseudomales. Furthermore, MT modulated the TGF-β signaling and steroid hormone biosynthesis pathways, indicating its crucial role in S. schlegelii sex differentiation. Therefore, the current study provides a method for achieving sexual reversal using MT in S. schlegelii and offers an initial insight into the underlying mechanism of sexual reversal in this species.

Effects of Bacillus cereusYB1 on growth, intestinal digestive enzyme activity, liver antioxidant enzyme activity, and intestinal structure of black rockfish, Sebastes schlegelii

AbstractWe aimed to investigate the effects of Bacillus cereus YB1 on the growth, intestinal digestive enzyme activity, liver antioxidant enzyme activity, and intestinal tissue structure of juvenile black rockfish (Sebastes schlegelii). A 50‐day feeding experiment was conducted. Feeding was conducted in four diet groups: control group with no YB1 supplement in diet and three treatment groups E‐L, E‐M, and E‐H containing 105, 106, and 107 CFU/g YB1, respectively. The results revealed that the weight gain and specific growth rate of juvenile fish significantly increased, while the feed coefficient was reduced in all three diet treatment groups. This indicated that the growth of black rockfish was significantly and positively affected by YB1 feeding. Enzyme activity in the intestinal tract was not significantly affected by YB1. However, the activity of protease, amylase, and lipase increased because of YB1 treatment, except for the proteases in the E‐M diet group. Meanwhile, no significant differences were recorded in the activities of the antioxidant enzymes in liver, but the level of catalase, superoxide dismutase, and malondialdehyde activities in treatments shows a better performance compared with the control in overall perspective. Furthermore, the structural features of the intestine (i.e., number of intestinal villi, length of gut villi, and thickness of muscularis) was significantly elevated with the inclusion of B. cereus YB1 in the diet. These results reveal that dietary supplementation of B. cereus YB1 is beneficial to the boosting of enzymatic activities and structure of intestinal tissue as well as the antioxidative ability of liver tissue. Such findings suggest that fish growth would be improved under YB1 feeding conditions.

Regulatory roles of miRNA-530 in the post-transcriptional regulation of NF-κB signaling pathway through targeted modulation of IκBα in Sebastesschlegelii

MicroRNAs (miRNAs) are a crucial type of non-coding RNAs involved in post-transcriptional regulation. The playing essential regulatory roles in the NF-κB signaling pathway and modulate the host immune response to diverse pathogens by targeting IκBα. However, the regulatory mechanism of miRNAs in relation with IκBα in Sebastes schlegelii remains unclear. In our study, we identified two copies of IkBα gene in black rockfish (Sebastes schlegelii), namely IkBα1 and IkBα2. Moreover, we have discovered that miRNA-530 can activate the NF-κB signaling pathway by inhibiting the expression of IκBα, thereby inducing the inflammatory response. This project comprehensively investigated the interactive regulatory roles of miRNA-530 in the NF-κB signaling pathway at both cellular and in vivo levels, while also elucidating the regulatory relationships between miRNA-530 and IκBα. In conclusion, our research confirmed that miRNA-530 can target the 3′UTR region of IκBα, resulting in a decrease in the expression of IκBα at the post-transcriptional level and inhibiting its translation. The findings contribute to the understanding of the regulatory network of non-coding RNA in teleosts and its subsequent regulation of the NF-κB signaling pathway by miRNAs.

Deciphering dynamic interactions between spermatozoa and the ovarian microenvironment through integrated multi-omics approaches in viviparous Sebastes schlegelii.

The ovarian microenvironment plays a crucial role in ensuring the reproductive success of viviparous teleosts. However, the molecular mechanism underlying the interaction between spermatozoa and the ovarian microenvironment has remained elusive. This study aimed to contribute to a better understanding of this process in black rockfish (Sebastes schlegelii) using integrated multi-omics approaches. The results demonstrated significant upregulation of ovarian complement-related proteins and pattern recognition receptors, along with remodeling of glycans on the surface of spermatozoa at the early spermatozoa-storage stage (1 month after mating). As spermatozoa were stored over time, ovarian complement proteins were progressively repressed by tryptophan and hippurate, indicating a remarkable adaptation of spermatozoa to the ovarian microenvironment. Before fertilization, a notable upregulation of cellular junction proteins was observed. The study revealed that spermatozoa bind to ZPB2a protein through GSTM3 and that ZPB2a promotes spermatozoa survival and movement in a GSTM3-dependent manner. These findings shed light on a key mechanism that influences the dynamics of spermatozoa in the female reproductive tract, providing valuable insights into the molecular networks regulating spermatozoa adaptation and survival in species with internal fertilization.

Specific expression of CC chemokine CCL17 regulates ovarian development and cell cycle in response to female reproductive hormones on in female black rockfish, Sebastes schlegelii

CC chemokine ligand 17 (CCL17) is a CC chemokine present in various species, including fish and mammals. CCL17 plays an important role in various organs, including innate immune defense in mammals, but its role and histological expression in fish have not been elucidated yet. Black rockfish (Sebastes schlegelii) is an economically important aquatic organism in East Asia that has recently been damaged by diverse biological and environmental factors, resulting in enormous financial losses. Although the functions of various immunomodulatory genes in black rockfish have been studied, the histological expression and function of CCL17 from S. schlegelii (SsCCL17) have not been investigated. We conducted homology analysis of the SsCCL17 amino acid sequence in black rockfish by comparing it with those of mammalian, avian, and fish species. Additionally, we proved that SsCCL17 was considerably activated in the ovary and brain of black rockfish using histological analyses via staining with hematoxylin and eosin and in situ hybridization. Moreover, in primary cells collected from the ovarian tissues of black rockfish, cell cycle progression and the expressions of ovarian development-related genes in response to female reproductive hormones were confirmed by quantitative PCR. Finally, the modulatory role of SsCCL17 in ovarian development was assessed using siRNA transfection in primary cells isolated from ovarian tissues of black rockfish, Collectively, we determined the tissue-specific localization of SsCCL17 and its function in the ovary of S. schlegelii, for the first time.

Black rockfish（Sebastes schlegelii）nuclear progesterone receptor: Cloning, tissue distribution and potential role in ovoviviparity teleost pregnancy and parturition

Nuclear progesterone receptor (nPR) is a member of the nuclear receptor family known to play a critical role in gonad development, gametogenesis, and ovulation in vertebrates, and also important in pregnancy maintenance and parturition in mammals. However, its biological functions in ovoviviparity teleosts are less clear. This study aimed to determine the possible role of nPR in fish oogenesis, pregnancy and parturition using black rockfish as a model. The npr, which consists of 2076 bp and codes for a 691 amino acids protein, was cloned. Phylogenetic analysis revealed that the nPR of black rockfish is more conserved in teleosts. Quantitative real-time PCR analyses in various tissues showed that npr was mainly detected in the pituitary followed by the ovary, testis and brain, while it was very low or undetectable in the spleen, head kidney, intestine and gill. During the gonadal development process, the npr level showed no variation in the ovary. In testis, the mRNA level of npr showed varied expression in different developmental stages with the highest level in the maturation stage. Detection of npr expression during fertilization and the perinatal period further showed that nPR may play important roles in the regulation of pregnancy and the parturition. In situ hybridization further revealed that npr mRNA was observed in the follicular cell layer during the perinatal period. The results from in vitro experiments showed that npr level was significantly downregulated when the primary cultured follicular cells during vitellogenesis (stage Ⅳ) were exposed to hCG. Studies using primary culture of black rockfish ovarian cells during the perinatal period, treated in vitro revealed that genes related to PGs synthesis (pla2g4a, cox2) and matrix metalloproteinases (mmp2, mmp9) were upregulated in response to 17,20β-P. However, treatment with 17,20β-P downregulated npr expression. In conclusion, these data suggest that nPR plays an essential role in fertilization, pregnancy maintenance and parturition in black rockfish.

Genome-Wide Characterization of the Hyaluronidase Gene Family and Their Potential Roles in Viviparous Black Rockfish (Sebastes schlegeli)

Genome-Wide Characterization of the Hyaluronidase Gene Family and Their Potential Roles in Viviparous Black Rockfish (Sebastes schlegeli)

Adaptive responses of feeding and swimming behaviors in black rockfish, Sebastes schlegelii, under starvation at juvenile and young stages

Starvation is a ubiquitous stress that many fish species have to cope with. To investigate the behavioral responses under this pressure in the fry stage, black rockfish (Sebastes schlegelii) at juvenile (29 days of age, 15.2 ± 1.0 mm in total length) and young (51 days of age, 40.3 ± 1.2 mm in total length) stages were starved for 12 and 21 days, respectively. During these two periods of starvation, the starved and routinely fed individuals (serving as the control group) were sampled to be analyzed the variations in growth, survival, feeding activity, swimming ability (cruise and burst), and diet transition process. The results indicated that juveniles were more sensitive to hunger, and the point of no return (PNR) was approximately 5.5 days (19 ℃ in water temperature). In contrast, the young fish had a significantly higher tolerance to starvation because the survival rate after 21 days of starvation was still higher than 99% (20 ℃). The total length and body weight of juveniles and young fish showed different degrees of negative growth. After the starvation for 1 day, the juveniles’ feeding activity on shrimps increased significantly (p < 0.05), while their cruising speed and time changed insignificantly. Similar results were observed in young fish been starved for 1–3 days. With the prolongation of starvation, however, both the feeding and cruising activities of black rockfish became significantly lower than those of the control groups (p < 0.05). The burst swimming ability did not seem to be affected by starvation time. Although the short-term starvation would not increase the young fish’s predation on shrimp, it might be serviceable for improving their feeding vitality. These behavioral results would help us understand the adaptive processes and response mechanisms of fish under starvation.

Evaluation of the Residency of Black Rockfish (Sebastes schlegelii) in Artificial Reef Areas Based on Stable Carbon Isotopes

Evaluation of the Residency of Black Rockfish (Sebastes schlegelii) in Artificial Reef Areas Based on Stable Carbon Isotopes