Jumbo Flying Squid Dosidicus Gigas Research Articles

Jumbo Flying Squid Distribution within Anticyclonic Eddies under Anomalous Climatic Conditions

Anticyclonic eddies are widely distributed off Peru, producing obvious effects on climate-environment-sensitive jumbo flying squid Dosidicus gigas . However, how the habitat of D. gigas changes within anticyclonic eddies during El Niño events is still unknown. Therefore, this study constructed a habitat model with different weights and screened the optimal performance model using fishery data from September to December during 2015 to 2019, as well as vertical water temperature data (sea surface temperature and 50 m water depth temperature) and surface chlorophyll concentration data (Chl-a). Then, combined with the eddy tracking dataset, the differences in the variation of resource abundance and habitat of D. gigas within the anticyclonic eddy between the 2015 El Niño year and the 2019 normal year were further comparatively analyzed based on the optimal habitat model. Compared with the normal year of 2019, the 2015 El Niño event occurred with a lower intensity of eddy activity, and both temperature in the fishing ground and near-surface sea water temperature within the anticyclonic eddy became warmer, with a small decrease in Chl-a; the percentage of suitable near-surface water temperature within the anticyclonic eddies decreased significantly, and suitable Chl-a decreased slightly; the suitable habitat for D. gigas was reduced dramatically, which was unfavorable to D. gigas survival. Our finding suggested that that anomalous climatic events can have an impact on eddy strength, as well as on the suitable environment and habitat within the anticyclonic eddies, resulting in variations in the abundance of D. gigas .

Decadal Changes in the Annual Growth of Two Commercial Ommastrephid Species in the Pacific Ocean

Neon flying squid Ommastrephes bartramii and jumbo flying squid Dosidicus gigas are two important commercial ommastrephid species in the Pacific Ocean. As short-lived marine species, squids are highly susceptible to changes in climate and marine environments. According to samples collected from the northwest and southeast Pacific Ocean in different years, we explored the growth characteristics of these two squids in terms of their mantle length (ML) distribution and the relationship between mantle length and body weight (LWR), also considering the relative condition factors (Kn), and explored the effects of the El Niño and Southern Oscillation (ENSO) on their growth. The results showed that the ML for O. bartramii and D. gigas had significant differences among different years and different sexes (p < 0.01), and the size of females was larger than that of males. LWR showed that both squids demonstrated a positive allometric growth pattern (b > 3), and parameters a and b were influenced by year and sex. Furthermore, there were significant differences in Kn in both squids for different years and different sexes (p < 0.01), and their interannual fluctuations were quite significant. In conclusion, the alterations in the marine environment caused by climate change had a significant impact on the growth of O. bartramii and D. gigas in this study. ENSO events had opposite effects on the growth of both squid species.

Seasonal habitat patterns of jumbo flying squid Dosidicus gigas off Peruvian waters

Abstract Habitat modeling approach is a useful tool to detect potential habitat of pelagic fish species for better fishery exploitation and management. In this study, an integrated habitat modeling approach was applied to examine seasonal habitat patterns of an ecologically and economically important squid species Dosidicus gigas in the Southeast Pacific Ocean off Peruvian waters. Fisheries data of D. gigas and three crucial remotely-sensed environmental variables including sea surface temperature (SST), net primary production (NPP) and sea surface height anomaly (SSHA) during 2006–2015 were used to develop and validate the habitat model. Results revealed that the model output robust predictions of seasonal habitat suitability for D. gigas stock. Potential habitat exhibited strong seasonal variability, characterized by an expansion of suitable habitat during spring-autumn period and an extreme reduction in winter. These seasonal habitat patterns of D. gigas were largely driven by spatial distribution of favorable environmental conditions. Spatial correlation analysis indicated that the habitat quality of D. gigas was negatively correlated with SST in the areas between 8°–15°S and 87°–79°W and with SSHA on the whole fishing ground. However, a negative relationship was found between HSI values and NPP in the east of 84°W, but with a significantly positive correlation in the west of 84°W. In addition, seasonal variations of CPUEs and latitude distribution of fishing efforts were highly coincided with the variability trends in the area of suitable habitats and their latitudinal distributions. Interannual variability was shown in the averaged HSI of D. gigas. Furthermore, comparing to the strong El Nino year in 2015, the La Nina event in 2011 yielded more enlarged favorable regions of each environmental factor in each season, leading to form extremely high-quality habitats.

Examining spatiotemporal distribution and CPUE-environment relationships for the jumbo flying squid Dosidicus gigas offshore Peru based on spatial autoregressive model

The spatiotemporal distribution and relationship between nominal catch-per-unit-effort (CPUE) and environment for the jumbo flying squid ( Dosidicus gigas ) were examined in offshore Peruvian waters during 2009–2013. Three typical oceanographic factors affecting the squid habitat were investigated in this research, including sea surface temperature (SST), sea surface salinity (SSS) and sea surface height (SSH). We studied the CPUE-environment relationships for D. gigas using a spatially-lagged version of spatial autoregressive (SAR) model and a generalized additive model (GAM), with the latter for auxiliary and comparative purposes. The annual fishery centroids were distributed broadly in an area bounded by 79.5°–82.7°W and 11.9°–17.1°S, while the monthly fishery centroids were spatially close and lay in a smaller area bounded by 81.0°–81.2°W and 14.3°–15.4°S. Our results show that the preferred environmental ranges for D. gigas offshore Peru were 20.9°–21.9°C for SST, 35.16–35.32 for SSS and 27.2–31.5 cm for SSH in the areas bounded by 78°–80°W/82–84°W and 15°–18°S. Monthly spatial distributions during October to December were predicted using the calibrated GAM and SAR models and general similarities were found between the observed and predicted patterns for the nominal CPUE of D. gigas. The overall accuracies for the hotspots generated by the SAR model were much higher than those produced by the GAM model for all three months. Our results contribute to a better understanding of the spatiotemporal distributions of D. gigas offshore Peru, and offer a new SAR modeling method for advancing fishery science.

Ocean warming-induced range-shifting of potential habitat for jumbo flying squid Dosidicus gigas in the Southeast Pacific Ocean off Peru

Climate-induced ocean warming may have significant influences on abundance and geographic distribution of fish species and cause range shifts and/or expansions in their habitats. The jumbo flying squid Dosidicus gigas in the Eastern Pacific Ocean is an ecologically and commercially important species. With 1-year short lifespan, D. gigas is significantly affected by climatic and environmental variability. This study used the logbook data of the 2011–2015 Chinese squid-jigging fishery off Peruvian waters, coupled with sea surface temperature (SST) data, to explore the variations in seasonal habitat suitability and habitat distribution pattern for D. gigas in the Southeast Pacific Ocean under five scenarios: SST in recent years (2011–2015) and with 0.5 °C, 1.0 °C, 2.0 °C and 4.0 °C increases in relation to the climate variability. A fishing effort-based habitat suitability index (HSI) model was developed to estimate habitat quality of D. gigas and spatial distribution of suitable and optimal habitats in relation to ocean warming. Results indicated that obvious seasonal variations were observed in the SST on the fishing ground of D. gigas with spatial variability. HSI modeling approach in this study essentially captured habitat characteristics of D. gigas from spring to winter during 2011–2015. SST increase scenarios revealed that seasonal habitat suitability of D. gigas significantly reduced, and the percentages of suitable (HSI ≥ 0.6) and optimal (HSI ≥ 0.8) habitats occupying the fishing ground dramatically decreased due to the rising SST. Moreover, an obvious southeastward movement was observed in gravity centers of D. gigas habitat under the above-mentioned five scenarios. Our findings suggested that ocean warming was likely to result in the shrinkage and southeastward range-shift in the potential high-quality habitats of D. gigas in the Southeast Pacific Ocean off Peruvian waters.

Climate-driven latitudinal shift in fishing ground of jumbo flying squid (Dosidicus gigas) in the Southeast Pacific Ocean off Peru

ABSTRACTThe jumbo flying squid Dosidicus gigas is a pelagic squid species extensively distributed in the Eastern Pacific Ocean with climate-related geographical variability. An analysis was carried out to evaluate impacts of climatic and oceanographic variability on spatial distribution of D. gigas in the Southeast Pacific Ocean off Peru. Logbook data of the 2006–2013 Chinese squid-jigging fishery were used to determine latitudinal gravity centres (LATG) of fishing ground of D. gigas in relation to sea surface temperature (SST), chlorophyll-a (chl-a) concentration and sea surface height (SSH), coupled with the SST anomaly (SSTA) in the Niño 1 + 2 region. Results indicated that the SSTA in the Niño 1 + 2 region played crucial influences on SST, chl-a and SSH on the fishing ground of D. gigas. The LATG of D. gigas exhibited seasonal and interannual variability with closely associations with SST, chl-a, and SSH. Significantly positive relationships were found between monthly LATG and the average latitude of the most favourable contour lines of SST, chl-a, and SSH for D. gigas, with time lags at 0, 7, and 0 month, respectively. The spatial pattern of LATG largely responded to climate-induced oceanographic variability on the squid fishing ground: the Niño 1 + 2 SSTA became warm, the most favourable SST and SSH contour lines for D. gigas would move southward, resulting in a southward movement of the LATG; however, the Niño 1 + 2 SSTA shifted into cold episodes, the most favourable SST and SSH contour lines for D. gigas would shift northward, leading to a northward shift of the LATG. Our findings suggested that the SSTA in the Niño 1 + 2 region coupled with the most favourable contour lines of SST and SSH were the major drivers regulating the latitudinal movement of fishing ground of D. gigas in the Southeast Pacific Ocean off Peruvian waters.

Application of Loop-Mediated Isothermal Amplification (LAMP) for Rapid Detection of Jumbo Flying Squid Dosidicus gigas (D’Orbigny, 1835)

Rapid identification of commercially important squid species is essential to manage squid market and protect consumers’ interests. In this study, two sets of loop-mediated isothermal amplification (LAMP)-based assays were developed for identification of jumbo flying squid (Dosidicus gigas). After analyzing the D. gigas mitochondrial genes reported in GenBank, the mitochondrial cytochrome c oxidase subunit I (COI) gene was selected for designing species-specific primers. When incubated at 65 °C for 30 min, only D. gigas DNA can be detected by real-time fluorescence detection (RealAmp) or visual detection via SYBR Green® I staining (Visual-LAMP). The detection limits were 10 pg per reaction for purified D. gigas DNA, and 0.01 % w/w D. gigas in homogenized cephalopod mixtures. These methods can be applied to all kinds of processed squid and squid-containing products. They also have potential in on-site detection for the advantages of high specificity, high sensitivity, time saving, and ease in operation.

Ceramide aminoethylphosphonate from jumbo flying squid Dosidicus gigas attenuates the toxicity of cyanotoxin microcystin-LR

We have previously established the method for isolation of ceramide aminoethylphosphonate (CAEP) from jumbo flying squid Dosidicus gigas. In this study, we performed a MTT assay to evaluate the safety of CAEP to the cell lines for the application to health food and supplements. The CAEP did not show any cytotoxicity to various HEK293-transfectant cells. Next, we elucidated the positive function of CAEP to the somatic cells. Recently, we have reported that hepatotoxin microcystin-LR was taken up into the hepatocytes mediated by hepatocellular uptake transporters OATP1B1 and OATP1B3, and the cells were induced cytotoxicity subsequently. Cytotoxicity of microcystin-LR to permanently OATP1B3-expressing HEK293-OATP1B3 cells rather than to HEK293-OATP1B1 cells was preferentially attenuated by CAEP in a concentration-dependent manner. In addition, the enzyme activity of serine/threonine phosphatase, which was inhibited by microcystin-LR, was recuperated by co-exposure to CAEP. Furthermore, microcystin-LR-induced cellular protein phosphorylation were disrupted by CAEP exposure. These results suggested that CAEP is a promising remedy and/or preventive medicine for liver damage with microcystin-LR.

Fishery biology of the jumbo flying squid <i>Dosidicus gigas</i> off the Exclusive Economic Zone of Chilean waters

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.

Size increment of jumbo flying squid Dosidicus gigas mature females in Peruvian waters, 1989–2004

Changes in population structure of the jumbo flying squid Dosidicus gigas in Peruvian waters were studied based on size-at-maturity from 1989 to 2004. From 1989 to 1999, mature squid belonging to the medium-sized group prevailed, but from 2001 on, mature squids were larger. This change is not related to the changes in sea surface temperature and we hypothesized that it was caused by the population increase of mesopelagic fishes as prey.

The Humboldt squid Dosidicus gigas (Orbigny, 1835): History of the Berlin specimen, with a reappraisal of other (bathy-)pelagic “gigantic” cephalopods (Mollusca, Ommastrephidae, Architeuthidae)

A well preserved and with c. 1750 mm body length remarkably large specimen of an oegopsid squid, erroneously treated as representative of the giant squid ArchiteuthisSteenstrup, 1856, featured prominently in the exhibition and collection of the Natural History Museum in Berlin for most of the last century. The exact identity as well as its origin has long been obscured, though. We reviewed the evidence for the species assignment and re-identified this specimen as a representative of the pelagic Humboldt or jumbo flying squid Dosidicus gigas (Orbigny, 1835), family Ommastrephidae (arrow squids or flying squids). Following a brief account on the history of this specimen, that was studied and first mentioned 1894 by the curator of malacology in Berlin, Carl Eduard von Martens, we review relevant biological features of D. gigas, including data on the geographical distribution of this species, and compare it to other so-called “gigantic” squids, in particular to Architeuthis, adding a discussion of six other oegopsid families with large squids and of frequent misidentifications.

Remotely sensed mesoscale oceanography of the Central Eastern Pacific and recruitment variability in Dosidicus gigas

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 310:25-32 (2006) - doi:10.3354/meps310025 Remotely sensed mesoscale oceanography of the Central Eastern Pacific and recruitment variability in Dosidicus gigas Claire M. Waluda*, Paul G. Rodhouse British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK *Email: clwa@bas.ac.uk ABSTRACT: The Jumbo flying squid Dosidicus gigas has a short life span and is subject to rapid changes in population size. This species inhabits the Eastern Pacific, one of the most variable oceanic environments in the world, subject to the El Niño Southern Oscillation (ENSO). This study examined the influence of environmental variability on squid abundance off Peru using mesoscale oceanographic indicators derived from remotely sensed satellite imagery. In the fishery area off Peru, squid abundance was positively associated with sea surface temperatures (SST) between 17 and 22°C during July, corresponding to the peak of the fishery season. In the putative hatching area close to the Costa Rica Dome, squid abundance was positively associated with SST of between 24 and 28°C during September, prior to the start of the fishery season. Squid abundance is apparently strongly influenced by mesoscale variability linked to ENSO, with low levels of upwelling during the very strong El Niño of 1997 to 1998 leading to very low catches of squid off Peru. Variability in upwelling off Peru and in the Costa Rica Dome region may drive primary and secondary production and transport processes affecting the planktonic early life stages and also the availability of food and suitable habitat for adult squid. KEY WORDS: Costa Rica Dome · Dosidicus gigas · El Niño Southern Oscillation · Eastern Pacific · Fishery · Flying squid · Mesoscale oceanography · Upwelling Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 310. Online publication date: April 03, 2006 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2006 Inter-Research.

Concentration of statolith trace elements in the jumbo flying squid during El Niño and non-El Niño years in the eastern Pacific

Statoliths of the jumbo flying squid Dosidicus gigas (Cephalopoda: Ommastrephidae) in the eastern Pacific in 1995, 1996 (non-El Niño years) and 1997 (El Niño year) were analysed to observe whether unusual temperature increases due to El Niño was recorded in the concentration of trace elements. In addition to calcium (the major element), trace elements of manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and strontium (Sr) were detected. Strontium concentration in the calcified tissue of some aquatic animals changes with environmental variables. However, yearly comparisons revealed that Sr concentration did not significantly differ between the El Niño year and non-El Niño years. Instead, the Sr concentration differed with squid habitats. Strontium concentration in statoliths of D. gigas from Peruvian waters (high salinity) was significantly higher than those from Costa Rican waters (low salinity) regardless of El Niño.

Occurrence of jumbo flying squid Dosidicus gigas aggregations associated with the countercurrent ridge off the Costa Rica Dome during 1997 El Niño and 1999 La Niña

Factors responsible for aggregations of jumbo flying squid Dosidicus gigas, an important component of the marine food web and target of commercial fisheries off the Costa Rica Dome in the Eastern Tropical Pacific Ocean (ETP), were examined during 2 years of different extreme oceano- graphic conditions: fall 1997 El Nino and fall 1999 La Nina. A high abundance of squid occurred in association with the well-developed countercurrent ridge (upwelling) off the Costa Rica Dome during fall 1997, but not during fall 1999, when the countercurrent ridge was less developed. Two features of the well-developed countercurrent ridge were considered important for the occurrence of high jumbo flying squid concentrations. Firstly, subsurface chlorophyll a (chl a) maxima were formed along the countercurrent ridge, resulting in integrated chl a concentrations in the upper 100 m being relatively high considering the generally low productivity of the ETP during an El Nino event. Secondly, a strong salinity front formed along the North Equatorial Countercurrent, which is possibly responsible for re- tention of jumbo flying squid in the ridge. Large yellowfin tuna Thunnus albacares, which mainly feed on micronekton (small fishes, cephalopods and swimming crabs), as do jumbo flying squid, were also more highly concentrated along the countercurrent ridge during 1997 than during 1999. It was noted that skipjack tuna Katsuwonus pelamis and small yellowfin tuna, which mainly feed on zooplankton, were associated with the equatorial ridge in the ETP, indicating that prey faunal components may also play an important part in the close association of jumbo flying squid with the countercurrent ridge.

Age, growth and population structure of the jumbo flying squid Dosidicus gigas in Peruvian waters

Age, growth and population structure of the jumbo flying squid, Dosidicus gigas, from the jig fishery in Peruvian waters in 1992 were determined by reading daily increments in ground and polished sections of statoliths. The squid ranged in size from 192 to 965 mm dorsal mantle length (ML) and no squid were older than 1 year. Two size groups were present in the exploited population; one group of small individuals <490 mm ML and another group of larger individuals >520 mm ML, with maximum ages of 220 and 354 days, respectively. The date of hatching estimated by back-calculation, revealed the presence of two cohorts of small squid; one hatched in autumn/winter and recruited to the fishery in spring/summer and the other hatched in spring/summer and recruited to the fishery in autumn/winter.