The lanternfishes are mesopelagic fish that are highly productive as common bycatch of deep-sea shrimp trawlers,but they are often neglected or discarded.Despite being one of the dominant lanternfish species in the Ar...The lanternfishes are mesopelagic fish that are highly productive as common bycatch of deep-sea shrimp trawlers,but they are often neglected or discarded.Despite being one of the dominant lanternfish species in the Arabian Sea,little is known about the life history of Diaphus thiollierei and its role in marine ecosystems.In this study,103 D.thiollierei were collected in the Arabian Sea during October-November 2020 to study population growth based on sagittal otolith daily ages;and 10 fish collected during April–May 2021 were subjected to otolith microchemistry analysis to reconstruct the vertical migration in their life history using LA-ICP-MS technique.The standard length–dry weight(SL-DW)relationships for D.thiollierei revealed both negative allometric growth and a significant difference between the sexes.Using daily growth annuli counts on the sagittal section of otoliths,the von Bertalanffy growth equation for D.thiollierei was determined.The pattern of four elemental ratios(Sr to Ca,Mg to Ca,Li to Ca,and Ba to Ca)in sagittal otolith suggested that,in general,D.thiollierei descended continually after hatching until the post-larval(PL)stage when they reached a depth of approximately 200 m.Subsequently,from the PL stage to the post-metamorphosisⅡ(PMⅡ)stage,D.thiollierei likely further sank from 200 m to a depth of approximately 300 m,and then in the daytime they were at a depth of approximately 300–800 m to take refuge from predators.This pilot study explored to unravel the vertical migration during life history in D.thiollierei from sagittal otoliths,whereas further investigation on otolith is needed to better delineate the population ecology in detail,and thus to provide basic information for the exploitation of the lanternfish resource and the understanding of their ecological roles.展开更多
The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the S...The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs (P≥0.05), the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmed by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age (P<0.05). The age readings can be verified by plotting the sagittal OW versus the standard length for age groups, and the individuals with similar standard length but in different ages can be separated by sagittal OW frequency analysis. Mostly, the predicted ages using the regression between sagittal OW and ages are closed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore, the technique is applied for Pennahia macrocephalus with discussion in this paper.展开更多
Age and growth characteristics of crimson sea bream Paragyrops edita Tanaka in Beibu Gulf were studied through bottom trawling and gillnet fleets fishing from July 2006 to December 2007. A total number of 1155 individ...Age and growth characteristics of crimson sea bream Paragyrops edita Tanaka in Beibu Gulf were studied through bottom trawling and gillnet fleets fishing from July 2006 to December 2007. A total number of 1155 individuals, ranging from 49 to 249mm in standard length was examined. The age of the fish was determined from sagittal otoliths. One year growth was made up of one translucent and one opaque zone. A maximum likelihood estimation procedure was used to fit the Von Bertalanffy, Logistic and Gompertz growth functions to the length-at-age data. ARSS indicated that there were no significant differences in growth between sexes in the three growth models （P〉0.05）, and the Von Bertalanffy growth function Lr=292.8{1 cxp[-0.167（t＋1.l16）]} was selected as the most appropriate growth model according to Akaike＇s information criterion （AIC）.展开更多
The age,growth rates and length to weight relationships for the south-eastern Australian population of largehead hairtail(Trichiurus lepturus)were investigated for the first time.Age was estimated by counting annuli i...The age,growth rates and length to weight relationships for the south-eastern Australian population of largehead hairtail(Trichiurus lepturus)were investigated for the first time.Age was estimated by counting annuli in sectioned sagittal otoliths,with a maximum age of 8 years estimated for males and females.We found no sig-nificant differences in the growth rates of males and females over the size(12–78 cm pre-anal length(PL))and age(0–8 years)ranges sampled.However,females in our collection were larger on average than males,and all fish sampled>60 cm PL were female,suggesting that females may grow to larger sizes than males and that sampling of greater numbers of larger and older fish may be required in future.T.lepturus growth was described by the von Bertalanffy growth function parameters L_(∝)=74.89 cm PL,K=0.13yr^(-1)and t0=0.80 yr,with the L_(∝)being amongst the largest reported for the species.Growth was variable,with the sizes at any given age spanning up to 50 cm PL.Female T.lepturus increased in body weight relative to length faster than males,as has been reported in other populations.The length/weight relationship for the south-eastern Australian population was significantly different,with almost no overlap,from that reported for T.lepturus in the Arabian Sea.The substantial differences in growth rates,maximum sizes and body morphometrics of T.lepturus from south-eastern Australia in comparison to other populations globally are consistent with the hypotheses that it represents a distinct population,although investigations using additional population markers are required to verify this.展开更多
基金The fund from the Laoshan Laboratory under contract No.LSK202203802the National Programme on Global Change and Air-Sea Interaction under contract No.GASI-02-SCS-YD sum/spr/aut。
文摘The lanternfishes are mesopelagic fish that are highly productive as common bycatch of deep-sea shrimp trawlers,but they are often neglected or discarded.Despite being one of the dominant lanternfish species in the Arabian Sea,little is known about the life history of Diaphus thiollierei and its role in marine ecosystems.In this study,103 D.thiollierei were collected in the Arabian Sea during October-November 2020 to study population growth based on sagittal otolith daily ages;and 10 fish collected during April–May 2021 were subjected to otolith microchemistry analysis to reconstruct the vertical migration in their life history using LA-ICP-MS technique.The standard length–dry weight(SL-DW)relationships for D.thiollierei revealed both negative allometric growth and a significant difference between the sexes.Using daily growth annuli counts on the sagittal section of otoliths,the von Bertalanffy growth equation for D.thiollierei was determined.The pattern of four elemental ratios(Sr to Ca,Mg to Ca,Li to Ca,and Ba to Ca)in sagittal otolith suggested that,in general,D.thiollierei descended continually after hatching until the post-larval(PL)stage when they reached a depth of approximately 200 m.Subsequently,from the PL stage to the post-metamorphosisⅡ(PMⅡ)stage,D.thiollierei likely further sank from 200 m to a depth of approximately 300 m,and then in the daytime they were at a depth of approximately 300–800 m to take refuge from predators.This pilot study explored to unravel the vertical migration during life history in D.thiollierei from sagittal otoliths,whereas further investigation on otolith is needed to better delineate the population ecology in detail,and thus to provide basic information for the exploitation of the lanternfish resource and the understanding of their ecological roles.
基金Supported by the National Natural Science Foundation of China (No. 30771653)Bureau of Fisheries, Ministry of Agriculture
文摘The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs (P≥0.05), the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmed by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age (P<0.05). The age readings can be verified by plotting the sagittal OW versus the standard length for age groups, and the individuals with similar standard length but in different ages can be separated by sagittal OW frequency analysis. Mostly, the predicted ages using the regression between sagittal OW and ages are closed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore, the technique is applied for Pennahia macrocephalus with discussion in this paper.
基金the National Natural Science Foundation of China (30771653)the program Fish Stock Investigation and Assessment of Beibu Gulf,Ministry of Agriculture,P R China (0509109)
文摘Age and growth characteristics of crimson sea bream Paragyrops edita Tanaka in Beibu Gulf were studied through bottom trawling and gillnet fleets fishing from July 2006 to December 2007. A total number of 1155 individuals, ranging from 49 to 249mm in standard length was examined. The age of the fish was determined from sagittal otoliths. One year growth was made up of one translucent and one opaque zone. A maximum likelihood estimation procedure was used to fit the Von Bertalanffy, Logistic and Gompertz growth functions to the length-at-age data. ARSS indicated that there were no significant differences in growth between sexes in the three growth models （P〉0.05）, and the Von Bertalanffy growth function Lr=292.8{1 cxp[-0.167（t＋1.l16）]} was selected as the most appropriate growth model according to Akaike＇s information criterion （AIC）.
基金supported by funding from the NSW Saltwater Recreational Fishing Trust(grant number SS022),Western Sydney University,and the NSW Department of Primary Industries.
文摘The age,growth rates and length to weight relationships for the south-eastern Australian population of largehead hairtail(Trichiurus lepturus)were investigated for the first time.Age was estimated by counting annuli in sectioned sagittal otoliths,with a maximum age of 8 years estimated for males and females.We found no sig-nificant differences in the growth rates of males and females over the size(12–78 cm pre-anal length(PL))and age(0–8 years)ranges sampled.However,females in our collection were larger on average than males,and all fish sampled>60 cm PL were female,suggesting that females may grow to larger sizes than males and that sampling of greater numbers of larger and older fish may be required in future.T.lepturus growth was described by the von Bertalanffy growth function parameters L_(∝)=74.89 cm PL,K=0.13yr^(-1)and t0=0.80 yr,with the L_(∝)being amongst the largest reported for the species.Growth was variable,with the sizes at any given age spanning up to 50 cm PL.Female T.lepturus increased in body weight relative to length faster than males,as has been reported in other populations.The length/weight relationship for the south-eastern Australian population was significantly different,with almost no overlap,from that reported for T.lepturus in the Arabian Sea.The substantial differences in growth rates,maximum sizes and body morphometrics of T.lepturus from south-eastern Australia in comparison to other populations globally are consistent with the hypotheses that it represents a distinct population,although investigations using additional population markers are required to verify this.
