Modeling the Spatial Distribution of Swordfish (Xiphias gladius) Using Fishery and Remote Sensing Data: Approach and Resolution

Remote Sensing, Journal Year: 2020, Volume and Issue: 12(6), P. 947 - 947

Published: March 15, 2020

Swordfish, Xiphias gladius (Linnaeus, 1758), is a commercially important species that widely distributed throughout three oceans. This inhabits oceanic waters with preferred environmental ranges and migrates vertically to the surface layer for feeding. However, spatial distribution pattern habitat preferences of swordfish have been rarely studied in Pacific Ocean due wide geographic range this species. study examined variables using two approaches, generalized additive models suitability index methods, different spatio-temporal data resolution scales. Results indicated sea temperature most factor determining distribution. Habitat ranges, estimated various modeling were robust relative The validated by examining consistency between predictions untrained actual observations, which all predicted high density tropical central Ocean, no obvious seasonal movement. from study, based on fishery remote sensing coverage, could benefit conservation management fisheries highly migratory such as tuna.

Language: Английский

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Development of a predation index to assess trophic stability in the Gulf of Alaska

Ecological Applications, Journal Year: 2020, Volume and Issue: 30(7)

Published: May 13, 2020

Abstract Predation can have substantial and long‐term effects on the population dynamics of ecologically important prey. Diverse predator assemblages, however, may produce stabilizing (i.e., portfolio) prey mortality when consumption varies asynchronously among predators. We calculated spatiotemporal variation in predation a dominant forage species to quantify synchrony portfolio food web context better understand diversity–stability relationships large marine ecosystem that has undergone considerable changes community composition. selected Walleye Pollock ( Gadus chalcogrammus ) as our case study because they support some largest, most valuable commercial fisheries world serve essential for an array economically culturally species. Thus, there are sufficient data with which test ecological theories empirical setting. Spatially explicit indices accounted annual biomass, bioenergetics‐based rations, age‐specific proportions consumed by suite groundfishes Gulf Alaska (1990–2015). found Arrowtooth Flounder Atheresthes stomias was, far, (proportional consumption: 0.74 ± 0.14). also synchronous trends species, indicating lack at basin scale. This combination single suggests strong top‐down control over Alaska, though degree was highly variable all spatial scales. Whereas generally increased western subregion, central became less through time. diminished trophic stability one area another, thereby emphasizing importance heterogeneity maintaining structure function. Finally, total (ranging from 1.87 7.63 Tg) often exceeded assessment‐based estimates productivity. assert using holistic empirically derived index modifier assumed constant natural would provide practical method incorporating information into single‐species stock assessments.

Language: Английский

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Modeling in an integrated ecosystem research framework to explore recruitment in Gulf of Alaska groundfish – Applications to management and lessons learned

Deep Sea Research Part II Topical Studies in Oceanography, Journal Year: 2022, Volume and Issue: 197, P. 105048 - 105048

Published: Feb. 16, 2022

Language: Английский

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Catchment-scale stream network spatio-temporal models, applied to the freshwater stages of a diadromous fish species, longfin eel (Anguilla dieffenbachii)

Fisheries Research, Journal Year: 2022, Volume and Issue: 259, P. 106583 - 106583

Published: Dec. 12, 2022

Language: Английский

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Linking the movement of South African sardine and anchovy to environmental variables using a model of intermediate complexity

Fisheries Research, Journal Year: 2024, Volume and Issue: 275, P. 107001 - 107001

Published: April 15, 2024

This study investigates the movement of sardine and anchovy between areas around South Africa, its possible relationship with key environmental drivers using a Model Intermediate Complexity for Ecosystems (MICE). model includes biomass-based, age- area-structured population dynamics to account these species' major life history migrations links variables fish movement. In addition movement, accounts growth, recruitment, natural fishing mortality. The environment-linked models use sea surface temperature (SST) an upwelling index southern Benguela Agulhas Bank as drivers. SST were selected because have consistently been identified potential in Africa. Eight developed this study, without are compared. parameters estimated by fitting hydro-acoustic survey recruit total biomass data, daily egg production method estimates spawning biomass, primary data from 1987 2014. These spatially disaggregated adequately reproduced historical adult biomass. results found that relationships relatively stronger than those sardine, especially upwelling. However, none models, which greater variability residuals substantially improved representation species fit indices abundance. MICE intended strategic purposes inclusion link could be used basis evaluating impact future climate changes on populations under alternative scenarios.

Language: Английский

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