Understanding patterns of distribution shifts and range expansion/contraction for small yellow croaker (Larimichthys polyactis) in the Yellow Sea

Fisheries Oceanography, Journal Year: 2020, Volume and Issue: 30(1), P. 69 - 84

Published: Sept. 3, 2020

Abstract Detecting and analyzing patterns of distribution shifts range expansion/contraction is important to understand population dynamics changes in stock status. Here, we develop a spatio‐temporal model for yellow croaker ( Larimichthys polyactis ), which was fitted bottom trawl survey biomass data collected the Yellow Sea winter 2001–2017. The accounts both spatial structure can potentially include effects surface temperature an annual index, Pacific Decadal Oscillation, represented using recently developed spatially varying coefficient model. We selected with no covariates based on Akaike's information criterion. center gravity found move northwest between 2001 2010, then southwest over period 2010–2017. These results reflected predicted progressive disappearance density hotspots (i.e., highest areas) north southeast areas Sea, resulted central area becoming only hotspot 2017. This finding has implications fisheries management context China–South Korea agreement, as it indicates measurable displacement toward China. exclusion from not expected priori may be due facts that environmental variations are pronounced representation models large proportion variability data.

Language: Английский

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The potential impact of a shifting Pacific sardine distribution on U.S. West Coast landings

Fisheries Oceanography, Journal Year: 2021, Volume and Issue: 30(4), P. 437 - 454

Published: Feb. 7, 2021

Abstract Many fish species are shifting spatial distributions in response to climate change, but projecting these shifts and measuring their impact at fine scales challenging. We present a simulation that projects change fishery landings due distribution shifts, by combining regional ocean biogeochemical models (forced three earth system models, ESMs: GFDL‐ESM2M, HadGEM2‐ES, IPSL‐CM5A‐MR), correlative for port‐level landings, framework which provides realistic values abundance conditions using an historical “reference period”. demonstrate this approach the northern subpopulation of Pacific sardine, iconic commercial U.S. West Coast. found northward shift sardine (based on subpopulation's habitat suitability), with projected declines southern ports (20%–50% decline 2080) increase (up 50%) or no ports, was consistent across ESMs. Total were more uncertain, HadGEM2 indicating 20% from 2000 15 levels 2070 (a rate 170 mt/y), IPSL 10% (115 GFDL 15% year ~2050 followed sharp decrease. The ESMs also differed timing fishing season frequency closures. Our identified key constraints future can be targeted tactical assessment; included seasonality quota allocation other catch portfolio.

Language: Английский

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Estimating fine‐scale movement rates and habitat preferences using multiple data sources

Fish and Fisheries, Journal Year: 2021, Volume and Issue: 22(6), P. 1359 - 1376

Published: Aug. 3, 2021

Abstract Fisheries scientists and managers must track rapid shifts in fish spatial distribution to mitigate stakeholder conflict optimize survey designs, these result part from animal movement. Information regarding movement can be obtained selection experiments, tagging studies, flux through gates (e.g. acoustic arrays), fishery catch‐per‐unit effort (CPUE), resource surveys genetic/chemical markers. However, there are few accessible approaches combine data types while accounting for spatially correlated residual patterns. We therefore discuss a model involving diffusion (random movement), taxis (movement towards preferred habitat) advection (passive drift following ocean currents). specifically outline how processes fitted discretizing space time estimating non‐linear habitat preferences using environmental layers as well process errors. Finally, we introduce an R package, ATM, by fitting the bottom trawl survey, longline Pacific cod ( Gadus macrocephalus , Gadidae) Bering Sea during winter/summer seasons 1982 2019. Combining predicts increasing proportion of residing northern 2013 2019, estimates informative recent stock assessment model. fit sensitivity analyses dropping tag, or data, this analysis shows that necessary identify rates, about among biogeographic strata. This “hybrid” species help explain poleward movement, project distributions under future climate conditions evaluate alternative tag‐deployment scenarios designs.

Language: Английский

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Climate‐informed models benefit hindcasting but present challenges when forecasting species–habitat associations

Ecography, Journal Year: 2022, Volume and Issue: 2022(10)

Published: July 20, 2022

Although species distribution models (SDMs) are commonly used to hindcast fine‐scale population metrics, there remains a paucity of information about how well these predict future responses climate. Many conventional SDMs rely on spatially‐explicit but time‐invariant conditions quantify distributions and densities. We compared status quo ‘static' with more climate‐informed 'dynamic' assess whether the addition time‐varying processes would improve performance and/or forecast skill. Here, we present two groundfish case studies from Bering Sea – high latitude system that has recently undergone considerable warming. relied statistics (R 2 , % deviance explained, UBRE or GCV) evaluate for presence–absence, numerical abundance biomass arrowtooth flounder Atheresthes stomias walleye pollock Gadus chalcogrammus . then retrospective skill testing near‐term Retrospective enables direct comparisons between forecasts observations through process fitting forecasting nested submodels within given time series. found inclusion covariates improved hindcasts. However, dynamic either did not decreased relative static SDMs. This is likely result rapidly changing temperatures ecosystem, which required environmental were outside range observed values. Until additional model development allows fully predictions, (or persistence models) may serve as reliable placeholders, especially when anomalous anticipated. Nonetheless, our findings demonstrate support use rather than selecting priori based their ability species–habitat associations in past.

Language: Английский

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Spatially varying catchability for integrating research survey data with other data sources: case studies involving observer samples, industry-cooperative surveys, and predators as samplers

Canadian Journal of Fisheries and Aquatic Sciences, Journal Year: 2023, Volume and Issue: unknown

Published: June 15, 2023

Spatio-temporal models are widely applied to standardise research survey data and increasingly used generate density maps indices from other sources. We developed a spatio-temporal modelling framework that integrates (treated as “reference dataset”) sources (“non-reference datasets”) while estimating spatially varying catchability for the non-reference datasets. demonstrated it using two case studies. The first involved bottom trawl observer spiny dogfish ( Squalus acanthias) on Chatham Rise, New Zealand. second cod predators samplers of juvenile snow crab Chionoecetes opilio) abundance, integrated with industry-cooperative surveys in eastern Bering Sea. Our leveraged strengths individual (the quality reference dataset quantity data), downweighting influence datasets via estimated catchabilities. They allowed generation annual longer time-period provision one single index rather than multiple each covering shorter time-period.

Language: Английский

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