Background Restocking by introducing hatchery-reared fish into wild habitats aids in the restoration of fishery aquatic ecosystems and reefs to increase the abundance of fish resources,restore the ecological balance o...Background Restocking by introducing hatchery-reared fish into wild habitats aids in the restoration of fishery aquatic ecosystems and reefs to increase the abundance of fish resources,restore the ecological balance of water bodies,and enhance ecosystem functioning.Accurately,rapidly,and effectively evaluating the success of restocking using chemical markers(e.g.,strontium[Sr])remains challenging for fisheries management.Consequently,for nonlethal fish sampling,hard tissues,such as fin rays,have received increasing attention as a target for marking method.However,data on the differences in marking different types of fin rays remain limited.Therefore,we exposed juvenile blunt snout bream individuals(Megalobrama amblycephala)to 0(control group)or 800 mg/L of SrCl_(2)·6H_(2)O(marked group)for 5 days and transferred them into normal aerated water for post-immersion culture.We sampled their pectoral,dorsal,ventral,anal,and caudal fin rays.The Sr marks among the fin types were sampled at 0 and 20 days post-immersion and evaluated using an electron probe micro-analyzer(EPMA)for the five-day Sr/Ca ratios,along with line transect and Sr mapping analyses.Results Sr marking signatures were observed in all fin types in the marked group,with a success rate of up to 100%.Although marking efficiency varied among the different fin ray types,the highest Sr/Ca ratios were most often detected in the dorsal fin.Cross-sectional Sr concentration maps of all fin rays sampled showed high-Sr domains in the marked group;in contrast,the entire cross-sections of the control group displayed low Sr contents,indicating successful marking efficiency.Conclusions Fin ray Sr marking is a successful method for juvenile M.amblycephala,with the advantages of nonlethality and negligible sampling injuries,facilitating the rapid and effective evaluation of Sr marking in restocking M.amblycephala.展开更多
Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation i...Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).展开更多
Black rockfish Sebastes schlegelii juveniles （30-40 mm total length） were immersed in a range of calcein （CAL） solutions at concentrations ranging from 50 to 250 mg/L and alizarin red S （ARS） solutions at concen...Black rockfish Sebastes schlegelii juveniles （30-40 mm total length） were immersed in a range of calcein （CAL） solutions at concentrations ranging from 50 to 250 mg/L and alizarin red S （ARS） solutions at concentrations ranging from 100 to 500 mg/L in filtered seawater （salinity 30） for 24 h. Fluorescent marks were detected in otoliths （sagittae, asteriscus）, scales, fin rays （dorsal, pectoral, ventral, anal, and caudal fin rays）, and fin spines （dorsal, ventral, and anal fin spines） after a 60-d growth experiment. With the exception of 50-100 rng/L CAL, acceptable marks were produced in the otoliths and fin spines by all concentrations of CAL and ARS. In particular, marks were clearly visible under normal light in the sagittae, asteriscus, and fin spines offish immersed in 200 500 mg/L, 300-500 rag/L, and 200-500 mg/LARS, respectively. Scales and fin rays had acceptable marks at much higher concentrations （≥50 mg/L CAL, ≥300 mg/L ARS for scales and ≥50 mg/L CAL,≥200 mg/L ARS for fin rays）. The mark quality was highest （i.e., acceptable marks were observed in all sampled structures after immersion marking） in fish immersed in 150-250 mg/L CAL or 300-500 mg/LARS. In addition, there was no significant difference in survival and growth of marked fish compared with controls 60 d post-marking （P〉0.05）.展开更多
Using a unique adhesive locomotion system,the rock-climbing fish(Beaufortia kweichowensis)adheres to submerged surfaces and crawls both forwards and backwards in torrential streams.To emulate this mechanism,we present...Using a unique adhesive locomotion system,the rock-climbing fish(Beaufortia kweichowensis)adheres to submerged surfaces and crawls both forwards and backwards in torrential streams.To emulate this mechanism,we present a biomimetic robot inspired by the locomotion model of the rock-climbing fish.The prototype contains two anisotropic adhesive components with linkages connected to a linear actuator.Each anisotropic adhesive component consists of one commercial sucker and two retractable bioinspired fin components.The fin components mimic the abduction and adduction of pectoral and pelvic fins through the retractable part to move up and down.The robot prototype was tested on vertical and inverted surfaces,and worked successfully.These results demonstrate that this novel system represents a new locomotion solution for surface movement without detachment from the substrate.展开更多
Background:Reproducing populations of invasive carps(Hypophthalmichthys spp.)could alter aquatic food webs and negatively afect native fshes in the Mississippi National River and Recreation Area(MISS)and the St.Croix ...Background:Reproducing populations of invasive carps(Hypophthalmichthys spp.)could alter aquatic food webs and negatively afect native fshes in the Mississippi National River and Recreation Area(MISS)and the St.Croix National Scenic Riverway(SACN).However,proposed invasive carp barriers may also threaten populations of native migratory fshes by preventing movements of fsh between rivers that are necessary for life history requirements.In this study,nonlethal chemical techniques were used to provide baseline data related to the condition,trophic position,and migratory histories of lake sturgeon(Acipenser fulvescens)captured in the Mississippi and St.Croix Rivers.Results:Fish length and weight measurements and age estimates determined from pectoral fn rays demonstrated that lake sturgeon from the Mississippi River had greater lengths-at-age compared to sturgeon from the St.Croix River.However,length–weight relations were similar for sturgeon from the Mississippi and St.Croix Rivers.Lake sturgeon captured from diferent locations had distinguishable fatty acid signatures,and stable isotope analyses demonstrated that lake sturgeon from the Mississippi River generally feed at a higher trophic level than those in the St.Croix River.Strontium-to-calcium ratios(Sr:Ca)from fn ray cross sections indicated that sturgeon captured from the Mississippi River had higher Sr:Ca values than sturgeon captured from the St.Croix River,and natal origins and capture locations were not signifcantly diferent among sturgeon captured within individual rivers.Most sturgeon were captured in water with a similar Sr:Ca signature as their natal waters,indicating that there is some separation between populations of lake sturgeon in the St.Croix and Mississippi Rivers.However,Sr:Ca data indicated substantial variation in movement patterns among individual lake sturgeon,indicating that populations interact through migrations of individual fsh between rivers.Conclusions:Study results provide baseline condition and food web structure index data for assessing changes in lake sturgeon populations should invasive carps become established in these areas of the Mississippi and St.Croix Rivers.Controlled-exposure and telemetry studies would help verify and enhance the relations between Sr:Ca signatures in water and lake sturgeon pectoral fn rays to further assess mixing of sturgeons between rivers。展开更多
基金financed by project grant 2022YFF0608203 of the National Key Research and Development Programproject grant KYCX22_0706 of the Postgraduate Research&Practice Innovation Program of Jiangsu Province
文摘Background Restocking by introducing hatchery-reared fish into wild habitats aids in the restoration of fishery aquatic ecosystems and reefs to increase the abundance of fish resources,restore the ecological balance of water bodies,and enhance ecosystem functioning.Accurately,rapidly,and effectively evaluating the success of restocking using chemical markers(e.g.,strontium[Sr])remains challenging for fisheries management.Consequently,for nonlethal fish sampling,hard tissues,such as fin rays,have received increasing attention as a target for marking method.However,data on the differences in marking different types of fin rays remain limited.Therefore,we exposed juvenile blunt snout bream individuals(Megalobrama amblycephala)to 0(control group)or 800 mg/L of SrCl_(2)·6H_(2)O(marked group)for 5 days and transferred them into normal aerated water for post-immersion culture.We sampled their pectoral,dorsal,ventral,anal,and caudal fin rays.The Sr marks among the fin types were sampled at 0 and 20 days post-immersion and evaluated using an electron probe micro-analyzer(EPMA)for the five-day Sr/Ca ratios,along with line transect and Sr mapping analyses.Results Sr marking signatures were observed in all fin types in the marked group,with a success rate of up to 100%.Although marking efficiency varied among the different fin ray types,the highest Sr/Ca ratios were most often detected in the dorsal fin.Cross-sectional Sr concentration maps of all fin rays sampled showed high-Sr domains in the marked group;in contrast,the entire cross-sections of the control group displayed low Sr contents,indicating successful marking efficiency.Conclusions Fin ray Sr marking is a successful method for juvenile M.amblycephala,with the advantages of nonlethality and negligible sampling injuries,facilitating the rapid and effective evaluation of Sr marking in restocking M.amblycephala.
基金supported by the National Key Research and Development Program(Grant no.2022YFC2805200,2020YFB1313200)the National Natural Science Foundation of China(Grant no.52001260,52201381,52371338)Ningbo Natural Science Foundation(Grant no.2022J062).
文摘Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201003068)the National Natural Science Foundation of China(Nos.31172447,41176117)
文摘Black rockfish Sebastes schlegelii juveniles （30-40 mm total length） were immersed in a range of calcein （CAL） solutions at concentrations ranging from 50 to 250 mg/L and alizarin red S （ARS） solutions at concentrations ranging from 100 to 500 mg/L in filtered seawater （salinity 30） for 24 h. Fluorescent marks were detected in otoliths （sagittae, asteriscus）, scales, fin rays （dorsal, pectoral, ventral, anal, and caudal fin rays）, and fin spines （dorsal, ventral, and anal fin spines） after a 60-d growth experiment. With the exception of 50-100 rng/L CAL, acceptable marks were produced in the otoliths and fin spines by all concentrations of CAL and ARS. In particular, marks were clearly visible under normal light in the sagittae, asteriscus, and fin spines offish immersed in 200 500 mg/L, 300-500 rag/L, and 200-500 mg/LARS, respectively. Scales and fin rays had acceptable marks at much higher concentrations （≥50 mg/L CAL, ≥300 mg/L ARS for scales and ≥50 mg/L CAL,≥200 mg/L ARS for fin rays）. The mark quality was highest （i.e., acceptable marks were observed in all sampled structures after immersion marking） in fish immersed in 150-250 mg/L CAL or 300-500 mg/LARS. In addition, there was no significant difference in survival and growth of marked fish compared with controls 60 d post-marking （P〉0.05）.
基金This work is supported by the China Postdoctoral Science Foundation(No.2020M681843)the National Natural Science Foundation of China(Nos.51875507,51821093,and 51890885)+1 种基金the Zhejiang Provincial Natural Science Foundation for Distinguished Young Scholars(No.LR15E050001)the Zhejiang Provincial Natural Science Foundation of China(No.LY18E050003).
文摘Using a unique adhesive locomotion system,the rock-climbing fish(Beaufortia kweichowensis)adheres to submerged surfaces and crawls both forwards and backwards in torrential streams.To emulate this mechanism,we present a biomimetic robot inspired by the locomotion model of the rock-climbing fish.The prototype contains two anisotropic adhesive components with linkages connected to a linear actuator.Each anisotropic adhesive component consists of one commercial sucker and two retractable bioinspired fin components.The fin components mimic the abduction and adduction of pectoral and pelvic fins through the retractable part to move up and down.The robot prototype was tested on vertical and inverted surfaces,and worked successfully.These results demonstrate that this novel system represents a new locomotion solution for surface movement without detachment from the substrate.
基金funded by the National Resource Preservation Program,a nation-wide collaborative program,supported by the USGS Ecosystems Mission Area,through which USGS and National Park Service staf address priority research needs identifed by the National Park ServiceNational Park Service staf from the two National Park Service units represented in this study were involved in the development of the study proposalThe study proposal was reviewed and approved for funding by a panel of U.S.Geological Survey and National Park Service scientists.
文摘Background:Reproducing populations of invasive carps(Hypophthalmichthys spp.)could alter aquatic food webs and negatively afect native fshes in the Mississippi National River and Recreation Area(MISS)and the St.Croix National Scenic Riverway(SACN).However,proposed invasive carp barriers may also threaten populations of native migratory fshes by preventing movements of fsh between rivers that are necessary for life history requirements.In this study,nonlethal chemical techniques were used to provide baseline data related to the condition,trophic position,and migratory histories of lake sturgeon(Acipenser fulvescens)captured in the Mississippi and St.Croix Rivers.Results:Fish length and weight measurements and age estimates determined from pectoral fn rays demonstrated that lake sturgeon from the Mississippi River had greater lengths-at-age compared to sturgeon from the St.Croix River.However,length–weight relations were similar for sturgeon from the Mississippi and St.Croix Rivers.Lake sturgeon captured from diferent locations had distinguishable fatty acid signatures,and stable isotope analyses demonstrated that lake sturgeon from the Mississippi River generally feed at a higher trophic level than those in the St.Croix River.Strontium-to-calcium ratios(Sr:Ca)from fn ray cross sections indicated that sturgeon captured from the Mississippi River had higher Sr:Ca values than sturgeon captured from the St.Croix River,and natal origins and capture locations were not signifcantly diferent among sturgeon captured within individual rivers.Most sturgeon were captured in water with a similar Sr:Ca signature as their natal waters,indicating that there is some separation between populations of lake sturgeon in the St.Croix and Mississippi Rivers.However,Sr:Ca data indicated substantial variation in movement patterns among individual lake sturgeon,indicating that populations interact through migrations of individual fsh between rivers.Conclusions:Study results provide baseline condition and food web structure index data for assessing changes in lake sturgeon populations should invasive carps become established in these areas of the Mississippi and St.Croix Rivers.Controlled-exposure and telemetry studies would help verify and enhance the relations between Sr:Ca signatures in water and lake sturgeon pectoral fn rays to further assess mixing of sturgeons between rivers。
