Noise has the potential to induce physiological stress in marine fishes, which may lead to all sorts of ecological consequences. In the current study, we used the RNA-sequencing (RNA-seq) method to sequence the whole transcriptome of the brain in small yellow croaker (Larimichthys polyactis). The animals were exposed to a mix of noises produced by different types of boat played back in a tank, then the brain tissues were collected after the fish had been exposed to a 120 dB noise for 0.5 h. In total, 762 differently expressed genes (DEGs) between the two groups were identified, including 157 up regulated and 605 down regulated genes in the noise exposure group compared with the control group. Gene ontology (GO) enrichment analysis indicated that the most up regulated gene categories included synaptic membranes, receptor-mediated endocytosis and the neurotransmitter secretion process. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways found that endocytosis, cell adhesion molecules and the extracellular matrix (ECM) receptor interaction pathway were over-represented. Specifically, ECM-related genes, including lamin2, lamin3, lamin4, coll1a2, coll5a1 and col4a5 were down regulated in the noise exposure group, implying the impaired composition of the ECM. In addition, the behavioral experiment revealed that L. polyactis exhibited avoidance behaviors to run away from the noise source at the beginning of the noise exposure period. At the end of the noise exposure period, L. polyactis kept motionless on the surface of the water and lost the ability to keep their balance. Taken together, our results indicate that exposure to noise stress contributes to neurological dysfunction in the brain and impaired locomotor ability in L. polyactis.

Environmental assessments of underwater noise on marine species must be based on species‐specific hearing abilities. This study was to assess the potential impact of underwater noise from the East China Sea Bridge wind farm on the acoustic communication of the marbled rockfish. Here, the 1/3 octave frequency band of underwater noise was 125 Hz with the level range of 78–96 dB re 1 μPa, recorded at distances between 15‐20m from the foundation at wind speed of 3–5 m/s. Auditory evoked potential (AEP) and passive acoustic techniques were used to determine the hearing abilities and sound production of the fish. The resultes showed the lowest auditory threshold of Sebastiscus marmoratus was 70 dB at 150 Hz matching the disturbance sound ranging 140–180 Hz, which indicating the acoustic communication used in this species. However, the frequency and level of turbine underwater noise overlapped the auditory sensitivity and vocalization of Sebastiscus marmoratus. The wind turbine noise could be detected by fish and may have a masking effect on their acoustic communication. This result can be applied for further to the assessent of fish species released into offshore wind farm marine ranch.

The decline of Japanese eel (Anguilla japonica) populations in the Yangtze River estuary represents a critical conservation concern. Eleven-years of daily catch data during recruitment periods (i.e., January–April, 2012–2022) indicate that annual catch averaged from 153 to 1108 eels, and show a bimodal pattern in glass eel arrivals. Utilizing seasonal-trend decomposition and generalized additive models, we demonstrated a strong correlation between catch abundance, optimal water temperatures, and lunar cycles. An auto-regressive integrated moving average (ARIMA) model predicts an increase in glass eel numbers for 2023–2024 but also points to a concerning trend of delayed recruitment timing since 2016, attributable to the 0.48 °C per decade rise in sea surface temperatures. This delay correlates with a significant decrease in the average body weight of glass eels, suggesting potential energy deficits that may hinder successful upstream migration. This study not only furthers our understanding of glass eel recruitment dynamics but also underscores the urgent need for targeted conservation measures. Additionally, it highlights the importance of sustained, detailed monitoring to mitigate the detrimental effects of climate change on these eels, vital for preserving the Yangtze River’s ecological integrity.

This study assessed the impact of an acoustic stimulus on the behavioral responses and physiological states of the large yellow croaker (Larimichthys crocea). The test fish, with an average body weight of approximately 352.81 ± 70.99 g, were exposed to one hour of acoustic stimulation at seven different frequencies: 100 Hz, 125 Hz, 160 Hz, 200 Hz, 500 Hz, 630 Hz, and 800 Hz. The aim was to delineate the specific effects of acoustic stimulation on the behavior and physiological indices. The results show that acoustic stimulation significantly altered the behavioral patterns of the large yellow croaker, predominantly manifested as avoidance behavior towards the sound source. At a stimulus frequency of 630 Hz, the test fish exhibited continuous irregular motion and erratic swimming. Physiologically, one hour of exposure to acoustic stimulation notably affected the endocrine system. The levels of Epinephrine and thyroxine were significantly elevated at 200 Hz, while the cortisol levels did not show significant differences. Additionally, the lactic acid content significantly increased at 800 Hz, and the blood glucose content peaked at 630 Hz. This study discovered that sound frequencies of 200 Hz, 630 Hz, and 800 Hz led to a significant increase in the levels of Epinephrine, glucose, thyroid hormones, and lactate in large yellow croaker, consequently affecting their behavior. The changes in these physiological indicators reflect the stress response of the large yellow croaker in specific sonic environments, providing crucial insights into the physiological and behavioral responses of fish to acoustic stimuli.