Endangered, exploited glass eels (Anguilla anguilla) with critical levels of heavy metals and microplastics reveal both shipping and plastic spill threats

Environmental Pollution, Journal Year: 2025, Volume and Issue: unknown, P. 125824 - 125824

Published: Feb. 1, 2025

Language: Английский

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Impacts of Marine Heatwaves on Subsurface Temperatures and Dissolved Oxygen in the Chesapeake Bay

Journal of Geophysical Research Oceans, Journal Year: 2024, Volume and Issue: 129(3)

Published: Feb. 26, 2024

Abstract Subsurface impacts associated with Marine Heatwaves (MHWs) in estuaries are not well understood, largely due to data scarcity. Using over three decades (1986–2021) of observations from several monitoring programs, this study investigates subsurface temperature and dissolved oxygen (DO) anomalies surface MHWs the Chesapeake Bay (CB). Seasonal variability followed a simple 1‐D response heating downward heat transport diffusion controlled by seasonally variable stratification mixing. Two distinct regimes were found: thermally stratified spring‐summer regime, when positive confined mixed layer (SML); homogeneous fall‐winter regime. Additionally, (subsurface) temperatures elevated for months (days weeks) before after MHWs, indicating individual events shorter than timescales temperatures. A SML budget identified air‐estuary flux changes as leading driver MHW onsets declines, latent being dominant term. DO anomaly patterns more complex, considerable along‐channel gradients. Notable decreases (1–4 mg L −1 ) primarily occurred winter/spring below SML, hypoxic zone expanded spring through fall. Only small fraction these could be attributed temperature‐induced solubility changes, demonstrating that other physical and/or biogeochemical processes dominate during events. In CB, concurrent low persistent high compound on valuable ecosystem, event likely exacerbated climate change.

Language: Английский

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Increasing duration of heatwaves poses a threat to oyster sustainability in the Gulf of Mexico

Ecological Indicators, Journal Year: 2024, Volume and Issue: 162, P. 112015 - 112015

Published: April 11, 2024

The future of the wild oyster fishery in northern Gulf Mexico is largely uncertain due to changing environmental conditions and declining abundance harvestable oysters. Specifically, rising temperatures can directly impact physiological thresholds eastern (Crassostrea virginica) at all life history stages alter narrow ecological niche this occupies. likely most pronounced during atmospheric heatwaves, defined as three or more days above 90th percentile daily maximum air temperatures, which have been shown be increasing frequency. Increasing exposure high temperature extremes may contribute exacerbate an already fishery. Critical health recruitment i.e., addition new biomass, a dynamic process strongly driven by temperature. Here, we examine relationship between heatwave characteristics prediction poor recruitment, measured post-larval oysters (e.g. spat) below site-specific median density observed historically productive fisheries over 46-years (1976 – 2020) Mobile Bay, Alabama 21-years (1993 2014) Apalachicola Florida. We acquired measurements 50 years (1970 weather monitoring stations adjacent bays identify site specific annual events (maximum yearly temperature, consecutive days, number heatwaves). Then, with extreme heatwaves that exceeded 75th for 50-year were compared non-extreme events. Years total correlated low density. Across both bay systems, if 11 then occurred 83 % time. Extreme duration indicator has potential powerful tool managers forecast inform sustainable harvest based on year-to-year variability long-term warming trends. Our findings illustrate how multiple stressors resulting loss keystone species healthy resilient coastal ecosystems.

Language: Английский

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Role of maturation and mortality in portfolio effects and climate resilience

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

Published: Jan. 27, 2023

The portfolio effect plays a critical role in population productivity and stability. Age structure of spawning salmon represents an example effects such that the risks experiencing unfavorable conditions are spread across time. However, distribution maturation ages for Pacific ( Oncorhynchus spp.) is increasingly concentrated into fewer younger ages, which may impact resilience to climate change. We explored dynamics Sacramento River fall-run Chinook O. tshawytscha) under different age scenarios using life-cycle model compared two mechanisms can underlie these changes—mortality maturation. In addition, we tested whether promotes drought. found high diversity increased stability size harvest with low diversity. mean responded differently depending on underlying mechanism. Reduced mortality adult fish 4–5 escapement, whereas delayed decreased escapement. Overall, was able buffer against adverse droughts by reducing variability Our results suggest variable climate.

Language: Английский

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Climatic effects on the synchrony and stability of temperate headwater invertebrates over four decades

Global Change Biology, Journal Year: 2023, Volume and Issue: 30(1)

Published: Nov. 7, 2023

Abstract Important clues about the ecological effects of climate change can arise from understanding influence other Earth‐system processes on ecosystem dynamics but few studies span inter‐decadal timescales required. We, therefore, examined how variation in annual weather patterns associated with North Atlantic Oscillation (NAO) over four decades was linked to synchrony and stability a metacommunity stream invertebrates across multiple, contrasting headwaters central Wales (UK). Prolonged warmer wetter conditions during positive NAO winters appeared synchronize variations population community composition among within streams thereby reducing levels organization. This climatically mediated synchronization occurred all irrespective acid–base status land use, weaker where invertebrate communities were more functionally diverse. Wavelet linear models indicated that explained up 50% overall species abundances at timescale 4–6 years. The affect through local temperature, precipitation discharge, increasing hydrochemical variability sites might have contributed. Our findings illustrate large‐scale climatic fluctuations generated persistence inland freshwater ecosystems ways transcend catchment character. Protecting restoring functional diversity increase their against warmer, are analogues ongoing change. Catchment management could also dampen impacts provide options for adaptation.

Language: Английский

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МОРФОФУНКЦІОНАЛЬНА БУДОВА ЩУКИ ЗВИЧАЙНОЇ ESOX LUCIUS

Bulletin of Sumy National Agrarian University The series Veterinary Medicine, Journal Year: 2025, Volume and Issue: 3(66), P. 41 - 46

Published: Jan. 6, 2025

Esox Lucius щука звичайна належить до царства тварин, типу хордові, ряду щукоподібні, родина щукові, рід щука, а вид щука. При дослідженні будови щуки звичайної та риб в цілому першу чергу звертаємо увагу на зовнішній абрис цієї особини. Для абрису тіла користувалися тримірним виміром, щоб візуально уявляти розташування анатомічних складових відносно трьох площин. Щука це риба річкова, її форма стрілоподібне, витягнуте по довжині, допомагає цій рибі швидко рухатись, або навпаки стояти мілині охоті. Довжина може досягати півтора метра, вага тридцяти кілограмів. На тілі розрізняють ділянку голови, тулуб, плавці хвіст. Ці основні анатомічні складові і відрізняють різні види риб. Колір темно сірий з сріблястим відтінком. протязі всього шкіра вкрита кістковою лускою, заходить головну ділянку, потиличну зяброву кришку косими рядками заходячи одна за одну, спина темніша ніж черево, тулубі видні світлі плями різного розміру розташовані вздовж впоперек тіла. Ділянка голови у велика, займає майже одну третю всієї рибини, гарно розвинена, приплюснута дорсовентрально, починається ротовим отвором. має добре розвинені парні непарні плавці. Непарні спинний, анальний хвостовий. Хвостовий розділений дві частини, плямисте забарвлення. великій головній ділянці рот, носові отвори, зяброві отвори очі. Починається ділянка орально великим отвором, який тягнеться аж переднього края ока. Ротовий отвір утворений двома щелепами верхньою нижньою, кут рота вони формують доходить рострального краю очей. Мандібуля виступає трохи вперед верхню щелепу. верхньощелепній кістці аборально розміщена шкірна складка, яка з’єднує черепом обмежує бічні стінки ротової порожнини, чим зумовлений спосіб живлення щук. Очні яблука дорсолатерально мають шароподібну форму, не повік. Отвір райдужної оболонки великий круглу форму. По краям ока складка зрощена ростральною стінкою Аборально розташована зяброва прикрита зябровою кришкою. Від заднього широка нижньої щелепи назву перетинка. Разом обмежують щілину, які з’єднуються один одним правого лівого боків. Рострально від очей знаходиться вхід носову порожнину. Він представлений парами ніздрів різної форми, назальний форму круга, аборальний півмісяця. Прямо під цими отворами є порожнина яку через ніздрі потрапляє вода коли рухається, таким чином відбувається зміна води нюховій капсулі. Ротова великою ротовою щілиною, обмежена нерухомими губами. Закінчується ротова глоткою. Як похідні органів головної кишки тут зуби язик. Форма зубів конусовидна, більші розміщуються нижній щелепі. верхній щелепі піднебінні дрібні чисельні.

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Four decades of climatic fluctuations and fish recruitment stability across a marine‐freshwater gradient

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(17), P. 5104 - 5120

Published: May 18, 2022

Abstract Investigating the effects of climatic variability on biological diversity, productivity, and stability is key to understanding possible futures for ecosystems under accelerating climate change. A critical question estuarine is, how does influence juvenile recruitment different fish species life histories that use estuaries as nurseries? Here we examined spatiotemporal abundance trends environmental responses 18 frequently spend stage rearing in San Francisco Estuary, CA, USA. First, constructed multivariate autoregressive state‐space models using age‐0 abundance, freshwater flow ( ), sea surface temperature data SST ) collected over four decades. Next, calculated coefficients variation (CV) assess portfolio (1) within among species, (anadromous, marine opportunist, or dependent), whole community; (2) regions estuary. We found abundances varied space time (increasing, decreasing, dynamically stable); 83% cases, response conditions (wet/dry, cool/warm periods). Anadromous responded strongly upper estuary, opportunist and/or lower dependent had diverse across Overall, community when considered entire estuary lowest CV, provided strong insurance (2.4‐ 3.5‐fold increases stability, respectively). Spatial also increased although a lesser extent (up 1.6‐fold increases). Our study advances notion controlled by biocomplexity—life history diversity environment. However, intensified drought heatwaves may increase risk multiple consecutive failures synchronizing dynamics trajectories via Moran effects, potentially diminishing nursery function.

Language: Английский

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Marine heatwaves alter the nursery function of coastal habitats for juvenile Gulf of Alaska Pacific cod

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: June 27, 2024

Abstract Marine Heatwaves (MHWs) can directly influence survival of marine fishes, particularly for early life stages, including age-0 juveniles during their residence in coastal nursery habitats. However, the ability nurseries to support high fish densities, optimize foraging and growth, protect against predators may be altered MHWs. Gulf Alaska Pacific cod ( Gadus macrocephalus ) larval, juvenile, adult abundances declined dramatically following MHW events 2014–2016 2019. To evaluate function MHWs, we compared diet composition, recent size, condition, abundance throughout first summer before, during, between Diet shifted larger prey mysids, but did not appear growth. We observed faster growth rates yet even when accounting could explain higher body sizes August Together with lower near absence small by these patterns highlight potential size-selection a reduced habitats buffer environmental variability only number large “super survivors” persisting through summer.

Language: Английский

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A Spatiotemporal History of Key Pelagic Fish Species in the San Francisco Estuary, CA

Estuaries and Coasts, Journal Year: 2023, Volume and Issue: 46(4), P. 1067 - 1082

Published: April 11, 2023

Abstract Estuaries across the globe have been subject to extensive abiotic and biotic changes are often monitored track trends in species abundance. The San Francisco Estuary has deeply altered by anthropogenic factors, which is reflected substantial declines some native introduced fishes. To fish abundance, a multitude of monitoring programs conducted regular surveys, dating back late 1950s. While these surveys all designed population-scale they methodologically distinct, with different target species, varying spatial coverage sampling frequency, gear types. compensate for individual survey limitations, we modeled pelagic distributions integrated data from many programs. We fit binomial generalized linear mixed models spatiotemporal random effects map annual spatially explicit detection probabilities striped bass, Delta smelt, longfin threadfin shad, American shad years 1980 2017. Overall, probability declined approximately 50% bass now near zero two smelt while both experienced fluctuations only slightly reduced Detection decreased dramatically fishes Central South Delta, especially after year 2000. In contrast, Suisun Marsh North acted as refuge habitats levels decline or even increased species. Our modeling approach, using disparate datasets, demonstrates simultaneous driven highly estuary.

Language: Английский

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Quantifying larval dispersal portfolio in seabass nurseries using otolith chemical signatures

Marine Environmental Research, Journal Year: 2024, Volume and Issue: 196, P. 106426 - 106426

Published: Feb. 27, 2024

The temporal asynchronies in larvae production from different spawning areas are fundamental components for ensuring stability and resilience of marine metapopulations. Such a concept, named portfolio effect, supposes that diversifying larval dispersal histories should minimize the risk recruitment failure by increasing probability at least some successfully settle nursery. Here, we used reconstructive approach based on otolith chemistry to quantify European seabass, Dicentrarchus labrax, across six estuarine nursery northeast Atlantic Ocean. analysis natal trajectory signatures indicated hatch distinct environments then dispersed water masses featured contrasting chemical signatures. While trace elements appeared affected changes (Mn Sr), others varied spatially during stage but remained poorly fluctuation fish physiology (Ba, Cu, Rb Zn). We proposed two diversity metrics richness variations among populations reflect spatio-temporal origins trajectories (i.e., estimates portfolio). Along French coast, were maximum nurseries located proximity offshore sites complex hydrodynamic contexts, such as Mont St-Michel bay. Finally, our findings indicate was positively related with local abundance seabass juveniles, supporting assumption heterogeneity history contributes promote success nurseries.

Language: Английский

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