Page 133 - 《水产学报》2025年第7期

郭浩宇，等 水产学报, 2025, 49(7): 079610

Effects of physical enrichment and predator stress on growth, behavior and
respiratory metabolism of juvenile marbled rockfish
(Sebastiscus marmoratus)

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GUO Haoyu , XUE Xianglong , HUA Yujie , LIU Haoyu , LÜ Chenhang ,
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QI Yulu , CHAI Xuejun , ZHANG Xiumei 1*
1. Fisheries College, Zhejiang Ocean University, Zhoushan 316022, China;
2. Faculty of Environmental Science and Engineering,
Kunming University of Science and Technology, Kunming 650500, China;
3. Key Laboratory of Mariculture and Enhancement of Zhejiang Province,
Zhejiang Marine Fisheries Research Institute, Zhoushan 316021, China
Abstract: Stock enhancement based on hatchery-reared fish has become one of the most common forms of management prac-
tices in marine fisheries resource restoration. However, a lack of environmental stimulation contributes to the poor survival
adaptability of hatchery-reared fish in the wild, with negative consequences for post-release performance in natural environ-
ments. To investigate whether incorporating physical enrichment and predator stress into aquaculture environments can enhance
the survival adaptability of hatchery-reared fish, this study conducted a two-factor interaction experiment to examine the effects
of predator stress and physical enrichment on the growth, behavior, and respiratory metabolism of juvenile marbled rockfish
(Sebastiscus marmoratus).The findings are as follows: ① Physical enrichment significantly improved the final body weight of
the juveniles (P<0.05), demonstrating its positive effect on growth in controlled environments. On the other hand, prolonged
predator stress inhibited fish growth, leading to decreased final body weight, weight gain rate, and specific growth rate, high-
lighting the potential trade-offs of predator stress on growth. ② Predator stress did not have a significant impact on the activity
or boldness of juvenile marbled rockfish but did significantly reduce their exploratory behavior, suggesting a specific behavi-
oral adjustment under stressful conditions. ③ In the presence of predators, physical enrichment could increase activity of juven-
ile fish, indicating its role in promoting active behaviors even in predator-present environments. ④ Physical enrichment did not
significantly impact predator avoidance behavior responses, but long-term coexistence with predators significantly reduced the
cumulative duration spent in risky areas by the juvenile fish. This indicates the potential of predator stress to shape risk-avoid-
ance strategies over time. ⑤ Physical enrichment markedly reduced the oxygen consumption rate of juvenile fish (P<0.01),
suggesting a reduction in metabolic stress or enhanced energy efficiency. In contrast, predator stress significantly increased
oxygen consumption (P<0.05), reflecting heightened metabolic demands associated with stress responses. ⑥ Both physical
enrichment and predator stress had significant interaction effects on the exploratory behavior, activity levels, and respiratory
metabolism of the juveniles. These interactions provide critical insights into the mechanisms through which environmental
enrichment influences fish growth and behavioral adaptability. Based on these findings, this study recommends incorporating
physical enrichment and controlled predator stress exposure as part of the pre-release acclimation process for hatchery-reared
marbled rockfish. Such practices could effectively improve the environmental adaptability of hatchery-reared marbled rockfish,
thereby potentially enhancing their survival performance after releasing into the wild.
Key words: Sebastiscus marmoratus; environmental enrichment; predator stress; behavioral adaptability; respiratory metabolism
Corresponding author: ZHANG Xiumei. E-mail: xiumei1227@163.com
Funding projects: National Natural Science Foundation of China (32102755); Provincial Basic Public Welfare Research Pro-
gram of Zhejiang Province (LGN22C190015); Fundamental Research Funds for Zhejiang Provincial Universities and Research
Institutes (2024J001-2)

中国水产学会主办 sponsored by China Society of Fisheries https://www.china-fishery.cn
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