The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation

Shanghai, China

The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation

Shanghai, China

Time filter

Source Type

Chen X.,Shanghai Ocean University | Chen X.,The Key laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Tian S.,Shanghai Ocean University | Tian S.,The Key laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | And 4 more authors.
Chinese Journal of Oceanology and Limnology | Year: 2011

The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and identify their optimal habitat, we have developed a habitat suitability index (HSI) model using two potential important environmental variables - sea surface temperature (SST) and sea surface height anomaly (SSHA) - and fishery data from the main fishing ground (165°-180°E) during June and July of 1999-2003. A geometric mean model (GMM), minimum model (MM) and arithmetic weighted model (AWM) with different weights were compared and the best HSI model was selected using Akaike's information criterion (AIC). The performance of the developed HSI model was evaluated using fishery data for 2004. This study suggests that the highest catch per unit effort (CPUE) and fishing effort are closely related to SST and SSHA. The best SST- and SSHA-based suitability index (SI) regression models were SI SST-based = 0.7SI effort-SST + 0.3 SI CPUE-SST, and SI SSHA-based = 0.5SI effort-SSHA + 0.5SI CPUE-SSHA, respectively, showing that fishing effort is more important than CPUE in the estimation of SI. The best HSI model was the AWM, defined as HSI=0.3SI SST-based+ 0.7SI SSHA-based, indicating that SSHA is more important than SST in estimating the HSI of squid. In 2004, monthly HSI values greater than 0.6 coincided with the distribution of productive fishing ground and high CPUE in June and July, suggesting that the models perform well. The proposed model provides an important tool in our efforts to develop forecasting capacity of squid spatial dynamics. © 2011 Chinese Society for Oceanology and Limnology, Science Press and Springer-Verlag Berlin Heidelberg.


Cao J.,Shanghai Ocean University | Chen X.,Shanghai Ocean University | Chen X.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Chen X.,The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources | And 7 more authors.
Scientia Marina | Year: 2011

Generalized linear Bayesian (GLBM) non-hierarchical and hierarchical models were developed for standardization of catch per unit effort (CPUE). The GLBM containing the covariates of month, latitude, sea surface temperature (SST), sea surface salinity (SSS) and sea level height (SLH) had the best fit for the Chinese squid-jigging fishery of Ommastrephes bartramii in the northwest Pacific Ocean based on deviance information criteria. This best-fitting model tends to be more ecologically sound than other CPUE standardization models, such as generalized linear models and generalized additive models. GLBM was also used to deal with the problems of estimating stock abundance index (i.e. standardized CPUE) resulting from increased spatial heterogeneity of spatial dynamics of fishing efforts in the squid fishery by predicting the standardized CPUE for unfished areas. The standardized CPUE based on data including predicted CPUE of unfished areas was lower than the derived CPUE based on data with observed CPUE alone, in particular during the fishing peak of August to October. This study indicates that it is more appropriate to use the standardized CPUE derived from data including both predicted CPUE of unfished areas and observed CPUE of fished area as a stock abundance index. We suggest that the proposed method be used in CPUE standardization to account for impacts of large spatial heterogeneity of fishing efforts in fisheries.


Fang Z.,Shanghai Ocean University | Fang Z.,Collaborative Innovation Center for Distant Water Fisheries | Xu L.,Shanghai Ocean University | Xu L.,Collaborative Innovation Center for Distant Water Fisheries | And 14 more authors.
Fisheries Science | Year: 2015

Cephalopod beaks maintain a stable morphology, implying that they can be used to explore ecological influences on squid life history. Understanding the beak growth pattern can help us to improve knowledge of the trophic characteristics of squids and to estimate squid biomass. Sthenoteuthis oualaniensis is widely distributed in eastern tropical Pacific equatorial waters and has been caught commercially by Chinese squid jigging fleets since 2011. In this study, we randomly took 220 samples of S. oualaniensis with mantle lengths (ML) of between 119 and 351 mm and body weights (BW) of between 45 and 1975 g and measured six beak morphological variables for each sampled squid. The relationships between ML and all of the beak variables were power functions, except for upper lateral wall length (ULWL), upper crest length, and lower lateral wall length, which showed linear relationships with ML. The relationships between BW and the six beak variables were best fitted with power functions, and these functions can be used to estimate squid biomass from beak variable values. All of the beak morphological variables varied according to the maturity stage of the squid. Results of a post hoc comparison suggested that the values of beak morphological variables for immature squids (maturity stages I and II) showed significant differences from the corresponding values for mature squids (maturity stages III–V). These differences may result from changes in diet that occur during maturation, which affect the relevant mandibular muscle strength. The most common pigmentation stages (PS) encountered were II–V. The relationships of PS to ULWL and lower wing length were best described by exponential functions. Beak morphology and pigmentation of S. oualaniensis tended to change markedly with ontogenetic stage. It is easy to separate mature and immature squids based on their PS. This study provides important biological information on S. oualaniensis. © 2015, Japanese Society of Fisheries Science.


Lin D.,Shanghai Ocean University | Lin D.,Collaborative Innovation Center for National Distant water Fisheries | Chen X.,Shanghai Ocean University | Chen X.,Collaborative Innovation Center for National Distant water Fisheries | And 6 more authors.
Invertebrate Biology | Year: 2015

Energy investment in reproduction and somatic growth was investigated for summer spawners of the Argentinean shortfin squid Illex argentinus in the southwest Atlantic Ocean. Sampled squids were examined for morphometry and intensity of feeding behavior associated with reproductive maturation. Residuals generated from length-weight relationships were analyzed to determine patterns of energy allocation between somatic and reproductive growth. Both females and males showed similar rates of increase for eviscerated body mass and digestive gland mass relative to mantle length, but the rate of increase for total reproductive organ weight relative to mantle length in females was three times that of males. For females, condition of somatic tissues deteriorated until the mature stage, but somatic condition improved after the onset of maturity. In males, there was no correlation between somatic condition and phases of reproductive maturity. Reproductive investment decreased as sexual maturation progressed for both females and males, with the lowest investment occurring at the functionally mature stage. Residual analysis indicated that female reproductive development was at the expense of body muscle growth during the immature and maturing stages, but energy invested in reproduction after onset of maturity was probably met by food intake. However, in males both reproductive maturation and somatic growth proceeded concurrently so that energy allocated to reproduction was related to food intake throughout the process of maturation. For both males and females, there was little evidence of trade-offs between the digestive gland and reproductive growth, as no significant correlation was found between dorsal mantle length-digestive gland weight residuals. The role of the digestive gland as an energy reserve for gonadal growth should be reconsidered. Additionally, feeding intensity by both males and females decreased after the onset of sexual maturity, but feeding never stopped completely, even during spawning. © 2015 The American Microscopical Society.


Chen X.,Shanghai Ocean University | Chen X.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Tian S.,Shanghai Ocean University | Tian S.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | And 4 more authors.
Fishery Bulletin | Year: 2010

We developed a habitat suitability index (HSI) model to understand and identify the optimal habitat and potential fishing grounds for neon flying squid (Ommastrephes bartramii) in the Northwest Pacific Ocean. Remote sensing data, including sea surface temperature, sea surface salinity, sea surface height, and chlorophyll-a concentrations, as well as fishery data from Chinese mainland squid fleets in the main fishing ground (150-165°E longitude) from August to October, from 1999 to 2004, were used. The HSI model was validated by using fishery data from 2005. The arithmetic mean modeling with three of the environmental variables-sea surface temperature, sea surface height anomaly, and chlorophyll-a concentrations-was defined as the most parsimonious HSI model. In 2005, monthly HSI values >0.6 coincided with productive fishing grounds and high fishing effort from August to October. This result implies that the model can reliably predict potential fishing grounds for O. bartramii. Because spatially explicit fisheries and environmental data are becoming readily available, it is feasible to develop a dynamic, near real-time habitat model for improving the process of identifying potential fishing areas for and optimal habitats of neon flying squid.


Liu B.,Shanghai Ocean University | Chen X.,Shanghai Ocean University | Chen X.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Chen X.,The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources | And 6 more authors.
Scientia Marina | Year: 2010

The jumbo flying squid Dosidicus gigas is widely distributed in the eastern Pacific Ocean and supports an important fishery. Although many studies have been carried out on the biology of this species, limited biological information is available in the waters outside the Exclusive Economic Zone of Chile (EEZ) (20°S-41°S and 74°30'W-84°W). Three surveys were conducted in this area by the Chinese squid jigging vessels during the period from April 2006 to May 2008. The majority of the catch in the survey was from the two areas defined by 37°30'-41°S and 78°30'-80°W and by 25°-30°S and 76°-77°30'W. The sex ratio (M: F) of the catch was 1: 2.48. The mean mantle length (ML) was 376 mm for males with a range of 257-721 mm and 388.7 mm for females with a range of 236-837 mm. Two distinguished size classes, medium- and large-sized groups, were identified in this study with the medium-sized group (350-450 mm ML) consisting of 89% of the total catch. The sizes at first sexual maturity were 638 mm ML for females and 565 mm ML for males. This study suggests that all the individuals examined were hatched from March 2007 to February 2008, indicating that D. gigas might spawn all year around with a peak spawning time from November 2007 to January 2008. Most of the stomachs analyzed had food remains. The preys included three major groups: Fish (mainly lanternfish), cephalopods and crustaceans, but D. gigas was the dominant species in the stomach contents, showing strong evidence of cannibalism. The information obtained from this study improves our understanding of the fishery biology of D. gigas off Chile.


Liu B.,Shanghai Ocean University | Liu B.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Liu B.,The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources | Chen X.,Shanghai Ocean University | And 6 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2012

The Jumbo flying squid (Dosidicus gigas), one of the key abundant fisheries resources, is widely distributed in the eastern tropical Pacific Ocean off Costa Rica. The first survey of D. gigas in this area was carried out in the middle of 1990s by the Japanese squid jigging vessels,followed by the development of a small scale commercial fishery. A survey of D. gigas was conducted by Chinese squid jigging vessels to evaluate the distributions of fishery resources and fishing grounds and to understand the relationship between fishing ground and environmental variables including biotc and abiotic environment. In this paper, based on the zooplankton data sampled by the Chinese squid jigging vessels in the waters (4° 30' 10°24'N, 91°20' 100°00'W) of the eastern tropical Pacific Ocean off Costa Rica from July to August in 2009, we analyzed the species composition, abundance and spatial distribution of zooplankton to evaluate potential mechanisms of forming the D. gigas fishing grounds. This study showed that there were a wide range of zooplankton species in the survey area, including jellyfish (Hydroidomedusa, Siphonophorae, Scyphomedusae), Ostracods, Copepods, Amphipoda, Mysidacea, Euphausiids, Macrura, Brachyura, Sagittoidea, Caudata, Thaliacea, Polychaetes and Pteropods. In total, 13 categories and 115 kinds (excluding cephalopods larvae, fish eggs and larvae and pelagic larvae) were recorded, There were 23 species 17 genus 10 family 8 order in the Coelentera, 74 species 43 genus 30 family 8 order in the Crustacea, 4 species 1 genus 1 family 1 order in the Chaetognatha, 5 species 5 genus 3 family 3 order in the Urochordata, 6 species 5 genus 3 family 1 order in the Annelida, 3 species 3 genus 1 family 1 order in the Mollusca and other species including paralarvae and juvenile of fish and cephalopod and pelagic larva. The zooplankton species of high abundance included Copepoda and Sagittoidea, while Copepoda, Sagittoidea, Macrura and paralarvae and juvenile of fish and cephalopod were those occurring most frequently in the sample. The average biomass and abundance of zooplankton were (124. 78±176. 83) mg/ m 3 and (848±1219) ind/ m 3, respectively. Copepoda had the highest abundance reaching 727 ind/ m 3 followed by Sagittoidea which was 373 ind/ m 3 in abundance. It was found that the high yield of squid was distributed in the area with high abundance of zooplankton, and related to the copepods distribution. Distribution of cephalopods larvae is closely related to the Copepods and Sagittoidea. During the survey, the composition of zooplankton and its biomass were found to be influenced by the mound of cold water. Thus the composition and distribution of zooplankton in different seasons and its relationship with cold water mound require more studied in future with research efforts focusing on collecting more data over long time period.


Fang Z.,Shanghai Ocean University | Chen X.,Shanghai Ocean University | Chen X.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Chen X.,The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources | And 7 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2012

The Argentinean short-finned squid, Illex argenginus, is a common neritic specie with a wide distribution from approximately 22°S to 54°S along the continental shelf and slope waters and around the Falkland/Malvinas Islands in the Southwest Atlantic Ocean. It is a cepholopod species of great commercial importance targeted by international fishing fleets consisting of both jigging fleets from Asian countries and trawelers from European countries. This species also plays a crucial role in its marine ecosystem in the southwest Atlantic Ocean. The Argentinean short-finned squid had a complicated intrapopulation structrue. At least five major intraspecific stocks are defined based on length at maturity, spawning, hatching time and distribution of animals in early life history stages. Its hard structures, including beaks and statoliths, have stable morphological characteristics, and are resistance to corrosion to a certain extent and suitable for life history information storage. They are often used separately in previous studies, and few studies have used both hard structures in studying squid life history. In this study, using specimens of Argentinean short-finned squid collected by the Chinese squid Jigging fishery fleet during February to May in 2007 and from January to March in 2010, we extracted 625 pairs of statolith from statocysts and 787 pairs of beaks from buccal masses.Ten morphological variables were measured for statoliths and 12 morphological variables were measured for beaks. These morphological variable measurements were standardized using mantle length (ML), which were then used to compare differences among the stocks (i.e., South Patagonic Stock, SPS; and Bonaerensis-Northpatagonic Stock, BNS)and between the sexes. This study showed that the morphological variables of statolith and beak for BNS females were larger than those of males. However, for the SPS cohort, male morphological variables tended to be larger than those of females. A Student's t-test showed that for a given stock the statoliths had significant differences between the sexes in the following morphological variables: Total Statolith Length (TSL), Maximum Width (MW), Lateral Dome Length (LDL), Wing Length (WL), and Wing Width (WW) (P<0.05). For a given sex, significant differences between the two stocks were found in MW, Dorsal Lateral Length (DLL), Rostrum Lateral Length (RLL), and Wing Width (WW) (P<0.05). Student's t- test also showed that for a given stock beaks had significant differences between the sexes in Upper Hood length (UHL), Upper Crest length (UCL), Upper Rostrum length (URL), Upper rostrum width (URW), Upper Lateral Wall Length (ULWL), Lower Rostrum length (LRL) (P<0.01).For a given sex, significant differences were found in Lower Hood length (LHL), Lower crest length (LCL), LRL, Lower Rostrum width (LRW), Lower Lateral Wall Length (LLWL), Lower Wing Length (LWL) between the two stocks (P<0.01). The majority of data variability in principal component analysis of statolith could be explained by TSL/ML, DLL/ML, RW/ML, MW/ML for the BNS and by TSL/ML, RW/ML, WW/ML, DDL/ML for the SPS. The majority of data variability in principal component analysis of beaks could be explained by UHL/ML, UCL/ML, ULWL/ML and LRW/ML for the BNS and by UHL/ML,UCL/ML, ULWL/ML, URL/ML, LWL/ML, LRL/ML for the SPS. When statolith and beaks were used to establish the discrimination function, accuracy rates in distinguishing the two cohorts were above 60%. These findings suggested that the cohorts of Illex argentinus in the Southwest Atlantic Ocean could be morphologically indentified. However, more samples and longer time series of data may be needed for further validation of this approach and evaluation of uncertainty associated with the results.


Fang Z.,Shanghai Ocean University | Liu B.,Shanghai Ocean University | Liu B.,The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation | Liu B.,The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources | And 7 more authors.
Scientia Marina | Year: 2014

Cephalopods are becoming increasingly important in global fisheries as a result of increased landings and are playing an important ecological role in the trophic dynamics of marine ecosystems. Ommastrephes bartramii is a pelagic cephalopod species with two widely distributed spawning stocks in the North Pacific Ocean. It is also a major fishing target for the Chinese squid jigging fleets. Successful separation of these two spawning stocks is critical to fisheries management, but tends to be challenging because of their similar morphology. In this study we attempted to identify the stocks based on discriminant analyses of 9 morphological variables of statolith and 12 variables of beaks measured for O. bartramii samples in the North Pacific. A significant difference was revealed in the standardized beak and statolith variables between sexes in the northeast (NE) stock (P<0.05). The northwest (NW) stock showed significant differences between sexes for all variables (P<0.05) except for upper wing length (P>0.05), whereas the NW stock showed no significant difference in either sex for the statolith variables (P>0.05). The same sex also revealed different patterns with different hard structures between the two stocks. In t-tests females showed significant differences between stocks in statolith morphology (P<0.05) and beak morphology (P<0.05); males also showed this difference between cohorts in statolith variables (P<0.05) except dorsal dome length and wing length (P>0.05), but showed no difference between cohorts (P>0.05) in beak morphometric variables. With the combination of two standardized hard parts, correct classification of stepwise discriminant analysis (SDA) was raised by nearly 20% compared with using only one structure, although overlaps of the NW stock were still found in the scatter-plots. It is concluded that adding more appropriate hard structure variables will effectively increase the success of separating geographic stocks by the SDA method. © 2014 CSIC.

Loading The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation collaborators
Loading The Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation collaborators