许氏平鲉幼鱼对人工鱼礁模型不同阴影情况的行为响应OACSTPCD

The shadow effect is one of the main factors influencing the organism assemblage of artificial reefs.In order to explore the behavioral response of Sebastes schlegelii for reefs under different shadow situations,three experiments were designed,which included group A exploring the effect of the artificial reef model with different shadow areas,group B exploring the effect of the plate with different shadow areas without reef model present,and group C exploring the effect of the artificial reef model with same shadow areas but different number of opening hole.The experimental tank without the artificial reef model and the plate was used as the control group.A light source was fixed at the top of the experimental tank.The juveniles of S.schlegelii(body length,(5.06±0.09)cm;body mass,(3.22±0.16)g)were selected as the experimental animal.We observed and recorded the behavior and distribution characteristics of the juveniles in the experimental tank.The results showed that the occurrence rates of individuals around the reef model in the three experimental groups were all significantly higher than that in the control group and other areas.The occurrence rate increased with the increase of reef shadow area around the reef model in group A.Group B showed no significant difference in the occurrence rate around the reef model between the different experimental levels.Group C indicated the occurrence rate around the reef model was similar with 1 and 9 circle holes but higher than 4 and 6 openings.In addition to indicating a larger shadow area of the reef model caused more effective assemblage performance of the reef,our study also showed that a higher number of openings could provide better shelter and ensure the effect of organism assemblage when fixing the same shadow area.