Climate-driven zooplankton shifts cause large-scale declines in food quality for fish

Nature Climate Change, Год журнала: 2023, Номер 13(5), С. 470 - 477

Опубликована: Март 23, 2023

Abstract Zooplankton are the primary energy pathway from phytoplankton to fish. Yet, there is limited understanding about how climate change will modify zooplankton communities and implications for marine food webs globally. Using a trait-based ecosystem model resolving key groups, we find that future oceans, particularly in tropical regions, favour increasingly dominated by carnivorous (chaetognaths, jellyfish copepods) gelatinous filter-feeding (larvaceans salps) at expense of omnivorous copepods euphausiids. By providing direct energetic small fish, rise filter feeders partially offsets increase trophic steps between producers fish declining biomass increases zooplankton. However, experience reduced carrying capacity falling less nutritious as environmental conditions zooplankton, slightly exacerbating projected declines pelagic regions 2100.

Язык: Английский

---

Assessing the influence of abiotic factors on small pelagic fish distribution across diverse water layers in the Northwest Pacific Ocean through acoustic methods

Ecological Indicators, Год журнала: 2024, Номер 158, С. 111563 - 111563

Опубликована: Янв. 1, 2024

The Northwest Pacific Ocean is one of the most productive fisheries in world, with small pelagic fish constituting a substantial portion its fishery resources. Changes abiotic factors can affect distribution marine fish, but there are limited studies on relationship between and density vertical direction. This study used acoustic measurement data collected by scientific research vessel "Songhang" equipped Simrad EK 80 echosounder from June to July 2022, estimate resource different water layers 0 200 m. Furthermore, Generalized Additive Models (GAMs) were established for various layers, combined remote sensing such as temperature (Temp), salinity (Sal), net primary productivity (Nppv), well latitude (Lat) longitude (Lon) data, analyze influence abundance species. results showed that mean biomass densities estimated based method 3.12×105±1.42×106 ind/n mile2 5768.39±26224.76 kg/n mile2, respectively. Small resources exhibited predominant concentration within 0–50 m displayed significant accumulation phenomenon near Kuroshio Extension area each layer. GAMs indicated affecting vary across layers. Temp Lon appeared optimal all significantly contributed density. Variations lead differences Our emphasized necessity exploring provide support developing managing Ocean.

Язык: Английский

---

Forecasting shifts in habitat suitability across the distribution range of a temperate small pelagic fish under different scenarios of climate change

The Science of The Total Environment, Год журнала: 2021, Номер 804, С. 150167 - 150167

Опубликована: Сен. 8, 2021

Climate change often leads to shifts in the distribution of small pelagic fish, likely by changing match-mismatch dynamics between these sensitive species within their environmental optima. Using present-day habitat suitability, we projected how different scenarios climate (IPCC Representative Concentration Pathways 2.6, 4.5 and 8.5) may alter large scale European sardine Sardina pilchardus (a model species) 2050 2100. We evaluated variability species-specific optima allowing a comparison future scenarios. Regardless scenario, sea surface temperature salinity interaction current velocity distance nearest coast were main descriptors responsible for effects on sardine's distribution. Present-day potential "hotspots" neritic zones (<250 km) with water currents <0.4 m s-1, where SST was 10 22 °C SSS > 20 (PSU), average. Most among climatic habitats moderate low suitability. By end this century, suitability increase Canary Islands, Iberian Peninsula, central North Sea, northern Mediterranean, eastern Black Sea decrease Atlantic African coast, southwest English Channel, Western U.K. A gradual poleward-eastward shift also This most pronounced 2100 under RCP 8.5. In that sardines had 9.6% range expansion which included waters along entire Norway up into White Sea. As is mediated synergic fitness, it critical apply models robust underlying species-habitat data integrate knowledge full processes shaping productivity

Язык: Английский

---

Fisheries impact on the Sea of Marmara ecosystem structure and functioning during the last three decades

Frontiers in Marine Science, Год журнала: 2023, Номер 9

Опубликована: Янв. 13, 2023

The Sea of Marmara (SoM), without doubt, is one the most disturbed marine ecosystems Mediterranean basin. As a semi-enclosed and recognized eutrophic basin, it has unique natural characteristic by permanent stratification at ~25 m depth. SoM ecosystem under threat multiple stressors from excessive nutrient enrichment, overfishing, invasive species, habitat loss to climate change. Within this study, an assessment on structure functioning its changes over time have been achieved. Hence, we firstly evaluate period three decades 1990s 2010s using mass-balance Ecopath models, secondly, delineate prevailing in each period, thirdly determine how fishing impact contributed since finally establish baseline for management future studies ecosystem. comparison models’ results consecutive periods showed that energetic capacity decreased significantly while decrease cycling indices indicated became fragile anthropogenic disturbances. According theory indices, immature stage autotrophic succession, with very high total primary production, much more above unity greatly exceeds respiration. Our highlighted was bottom-up control exerted mesozooplankton; however, anchovy bottleneck energy transfers higher trophic levels creating also wasp-waist food-web. bycatch demersal species long life span, sharks rays, brought them brink going commercial extinction. Overall, were due cascades fisheries exploitation addition productivity system. We conclude concomitant impacts so diverse immediate action plan required. Therefore, propose tentative outlook will help monitoring better SoM.

Язык: Английский

---

Climate-induced small pelagic fish blooms in an overexploited marine ecosystem of the South China Sea

Ecological Indicators, Год журнала: 2022, Номер 145, С. 109598 - 109598

Опубликована: Окт. 29, 2022

Marine ecosystems are a primary conservation concern because of the separate and synergistic effects overfishing climate change on their productivity biodiversity. For purpose implementing ecosystem-based fisheries management, it is essential to understand how fish stocks respond in marine ecosystems, especially those that have been overexploited. The Beibu Gulf northwestern part South China Sea has long one China's major fishing grounds. After collapse demersal ecosystem 1990 s, small pelagic fishes, including Japanese jack mackerel (Trachurus japonicus) scad (Decapterus maruadsi), occupied more-important ecological niche this gulf. However, insufficient research creates great uncertainty for current management measures. This study used data trawl surveys environmental investigate possible mechanisms leading dramatic fluctuations populations ecosystem. Abnormal blooms fish, T. japonicus D. maruadsi, occurred following four La Niña events (in 2007/2008, 2010/2011, 2011/2012, 2020/2021). Moreover, dominant species shifted observably regularly, Shannon–Wiener diversity Pielou's evenness decreased significantly northeastern coastal waters gulf, spatial pattern community was reorganized summers probably resulted from combination change, overfishing, summer moratorium, which thereby caused series responses Fluctuations after seemed more stocks. Therefore, we emphasize need ecosystem-based, preventive, adaptive management.

Язык: Английский

---

Caught in the middle: bottom-up and top-down processes impacting recruitment in a small pelagic fish

Reviews in Fish Biology and Fisheries, Год журнала: 2022, Номер unknown

Опубликована: Дек. 4, 2022

Abstract Understanding the drivers behind fluctuations in fish populations remains a key objective fishery science. Our predictive capacity to explain these is still relatively low, due amalgam of interacting bottom-up and top-down factors, which vary across time space among within populations. Gaining mechanistic understanding recruitment requires holistic approach, combining field, experimental modelling efforts. Here, we use Western Baltic Spring-Spawning (WBSS) herring ( Clupea harengus ) exemplify power this approach high complexity (and their interactions). Since early 2000s, low levels have promoted intense research on stock. literature synthesis suggests that major are habitat compression spawning beds (due eutrophication coastal modification mainly) warming, indirectly leads changes phenology, prey abundance predation pressure. Other factors include increased intensity extreme climate events new predators system. Four main knowledge gaps were identified related life-cycle migration use, population structure demographics, life-stage specific impact multi-stressors, predator–prey interactions. Specific topics areas proposed, as well priority support sustainable management Given Sea severely impacted by altered precipitation, WBSS could be harbinger potential effects changing environmental small pelagic fishes other world. Graphical abstract

Язык: Английский

---

Risks and adaptation options for the Mediterranean fisheries in the face of multiple climate change drivers and impacts

ICES Journal of Marine Science, Год журнала: 2022, Номер 79(9), С. 2473 - 2488

Опубликована: Сен. 23, 2022

Abstract The Mediterranean Sea is among the most vulnerable semi-enclosed seas to climate change. Multiple oceanic changes occur besides warming that can generate numerous ecological, social, and economic risks, challenging fisheries management at various spatial scales—from local international. In this study, we applied a semi-quantitative risk assessment (CRA) small pelagic demersal in relation diversity of climate-related drivers impacts. We assessed risks change effects on resources, fishing operations, livelihoods, wider social implications seven sub-regions Sea. Ocean warming, an increase extreme weather events, vertical stratification resulted important drivers. Overall, present higher resources livelihoods than operations study puts into evidence geographic differences terms impacts, with south-eastern being sub-region levels for both fisheries, while north-central also showed fisheries. furthermore discusses plausible adaptive measures management, policy, research, be potentially address high priority as well implementation concerns technical effectiveness issues. Enhancing needs primary strategy region reverse number overfished stocks build resilience

Язык: Английский

---

Resolving the variability in habitat use by juvenile small pelagic fish in a major tidal system by continuous echosounder measurements

Marine Ecology Progress Series, Год журнала: 2023, Номер 741, С. 169 - 187

Опубликована: Июль 10, 2023

Shallow coastal areas are important nurseries for larvae and juveniles of many fish species. However, empirical data on small pelagic (SPF) in such regions lacking, temporal variability abundance habitat use by SPF unknown. Given the critical role as a trophic link, their commercial value sensitivity to climate variability, there is need quantitative high-resolution monitoring method. We deployed bottom-mounted echosounder, combined with water current profiler, examine variation density, vertical distribution movement behaviour Marsdiep, dynamic tidal inlet between North Sea Wadden Sea. The acoustic setup provided year-round records density column every 90 min. Monthly samples were collected help interpret observations. Our analyses indicated that Marsdiep migration gateway from into Sea, particularly juvenile herring sprat. observed clear seasonality high densities mid-spring early autumn. Fish typically used upper half column. Swimming was primarily driven currents. Yet, during outgoing tide, resisted outflowing current, suggesting efforts remain supporting hypothesis serves preferred nursery area SPF. frequency, multi-seasonal vertically resolved observations provide unique insight Furthermore, potential applications autonomous echosounder moorings discussed.

Язык: Английский

---

Forage Fish Species Prefer Habitat within Designated Offshore Wind Energy Areas in the U.S. Northeast Shelf Ecosystem

Marine and Coastal Fisheries, Год журнала: 2023, Номер 15(2)

Опубликована: Март 27, 2023

Abstract As the world develops sources of renewable energy, there is an intensifying interest in offshore wind energy production. The Northeast U.S. Continental Shelf (NES) ecosystem has favorable dynamics, with active development energy. In this study, we present species distribution models that consider both occupancy and biomass responses for a broad spectrum fish macroinvertebrate taxa ( n = 177). Building upon prior analyses, habitat was differentiated into overall core habitats based on statistical distributions scores. Overall used to show each species' regional fishery‐independent survey captures between 1976 2019, whereas represented where focus abundance located as subset habitat. Wind developments may modify water column ways impact lower‐trophic‐level productivity; therefore, added attention given response forage species. Over 20% showed preferential use putative potential areas, including disproportionate number taxa. Principal usage varied by season, like Atlantic Menhaden Brevoortia tyrannus Mackerel Scomber scombrus preferentially using lease areas spring Round Herring Etrumeus teres longfin inshore squid Doryteuthis pealeii autumn. For relatively low tendency related be lower than habitat; contrast, high higher area tended have positive trends across species, these being disproportionately among These results frame importance NES, particularly fulfill many important ecological functions.

Язык: Английский

---

Using predator diets to infer forage fish distribution and assess responses to climate variability in the eastern Bering Sea

Marine Ecology Progress Series, Год журнала: 2023, Номер 741, С. 71 - 99

Опубликована: Авг. 4, 2023

Forage fishes comprise an integral part of marine food webs in the highly productive ecosystems North Pacific. However, significant knowledge gaps exist related to status forage fish, their life histories, and how populations may react future climatic shifts. Standardized bottom trawl surveys are critical stock assessment groundfish but lack gear protocols quantitatively evaluate small pelagic fish. Where diet data available, predators be used as indirect method collecting on fish distribution relative abundance. We stomach contents infer predator-prey interactions eastern Bering Sea analyze 5 taxa over a 34 yr time series (1985-2019). Using 4 dominant predators, we constructed predator depth temperature habitat profiles center gravity (COG) analysis global index collocation examine overlap. Results provide insight partitioning competitive between species dynamics prey. Interannual COG analyses indicated recent periods cooling (2007-2013) warming (2014-2019) had effects suggest differences resilience climate change this region. Population shifts were particularly evident anomalous warming, highlighting need understand prolonged affect dynamics. also demonstrate importance these might inform multi-species models management strategies.

Язык: Английский

---