scholarly journals The effect of hypoxia on fish schooling

2017 ◽  
Vol 372 (1727) ◽  
pp. 20160236 ◽  
Author(s):  
Paolo Domenici ◽  
John F. Steffensen ◽  
Stefano Marras
Keyword(s):  
Climate Change ◽  
Multiple Stressors ◽  
Maximum Size ◽  
School Structure ◽  
Fish Behaviour ◽  
Low Oxygen ◽  
Fish Schools ◽  
Hypoxic Conditions ◽  
Trade Offs ◽  
Schooling Behaviour

Low-oxygen areas are expanding in the oceans as a result of climate change. Work carried out during the past two decades suggests that, in addition to impairing basic physiological functions, hypoxia can also affect fish behaviour. Given that many fish species are known to school, and that schooling is advantageous for their survival, the effect of hypoxia on schooling behaviour may have important ecological consequences. Here, we review the effects of hypoxia on school structure and dynamics, together with the mechanisms that cause an increase in school volume and that ultimately lead to school disruption. Furthermore, the effect of hypoxia generates a number of trade-offs in terms of schooling positions and school structure. Field observations have found that large schools of fish can exacerbate hypoxic conditions, with potential consequences for school structure and size. Therefore, previous models that predict the maximum size attainable by fish schools in relation to oxygen levels are also reviewed. Finally, we suggest that studies on the effect of hypoxia on schooling need to be integrated with those on temperature and ocean acidifications within a framework aimed at increasing our ability to predict the effect of multiple stressors of climate change on fish behaviour. This article is part of the themed issue ‘Physiological determinants of social behaviour in animals’.

From two dimensions to three: the use of multibeam sonar for a new approach in fisheries acoustics

1999 ◽  
Vol 56 (1) ◽  
pp. 6-12 ◽  
Author(s):  
François Gerlotto ◽  
Marc Soria ◽  
Pierre Fréon
Keyword(s):  
Three Dimensional ◽  
Two Dimensions ◽  
School Structure ◽  
Fish Behaviour ◽  
New Approach ◽  
Multibeam Sonar ◽  
Fish Schools ◽  
Fisheries Acoustics ◽  
Working Frequency ◽  
School Classification

We present a methodology applying multibeam sonar for three-dimensional (3D) observation of fish schools that enhances the conventional use of vertical scientific echo sounders. The sonar we employ has 60 beams of 1.5° each. Its working frequency is 455 kHz. It is applied on a vertical plan normal to the vessel route, observing from the surface line to the bottom with a range set to 100 m. The sampled volume is 14 times larger than the volume observed with vertical echo sounding. The contribution of this new methodology to fisheries acoustics is detailed for school classification, internal school structure, spatial distribution of schools, fish behaviour, and biomass estimates. For each of these points, we present some preliminary results with the aim of defining the real progress in fisheries acoustics research as a result of 3D acoustics. Finally, we present a list of technical and methodological improvements that we are developing in order to make multibeam sonar fully adapted to fisheries acoustics.

scholarly journals Hypoxia and the antipredator behaviours of fishes

2007 ◽  
Vol 362 (1487) ◽  
pp. 2105-2121 ◽  
Author(s):  
P Domenici ◽  
C Lefrançois ◽  
A Shingles
Keyword(s):  
Aquatic Organisms ◽  
Severe Hypoxia ◽  
Antipredator Behaviour ◽  
School Structure ◽  
Locomotor Performance ◽  
Aquatic Communities ◽  
Trade Off ◽  
Trade Offs ◽  
Schooling Behaviour ◽  
Escape Responses

Hypoxia is a phenomenon occurring in marine coastal areas with increasing frequency. While hypoxia has been documented to affect fish activity and metabolism, recent evidence shows that hypoxia can also have a detrimental effect on various antipredator behaviours. Here, we review such evidence with a focus on the effect of hypoxia on fish escape responses, its modulation by aquatic surface respiration (ASR) and schooling behaviour. The main effect of hypoxia on escape behaviour was found in responsiveness and directionality. Locomotor performance in escapes was expected to be relatively independent of hypoxia, since escape responses are fuelled anaerobically. However, hypoxia decreased locomotor performance in some species (Mugilidae) although only in the absence of ASR in severe hypoxia. ASR allows fish to show higher escape performance than fish staying in the water column where hypoxia occurs. This situation provides a trade-off whereby fish may perform ASR in order to avoid the detrimental effects of hypoxia, although they would be subjected to higher exposure to aerial predation. As a result of this trade-off, fishes appear to minimize surfacing behaviour in the presence of aerial predators and to surface near shelters, where possible. For many fish species, schooling can be an effective antipredator behaviour. Severe hypoxia may lead to the disruption of the school unit. At moderate levels, hypoxia can increase school volume and can change the shuffling behaviour of individuals. By altering school structure and dynamics, hypoxia may affect the well functioning of schooling in terms of synchronization and execution of antipredator manoeuvres. School structure and volume appear to be the results of numerous trade-offs, where school shape may be dictated by the presence of predators, the need for energy saving via hydrodynamic advantages and oxygen level. The effects of hypoxia on aquatic organisms can be taxon specific. While hypoxia may not necessarily increase the vulnerability of fish subject to predation by other fish (since feeding in fish also decreases in hypoxia), predators from other taxa such as birds, jellyfish or aquatic mammals may take advantage of the detrimental effects of hypoxia on fish escape ability. Therefore, the effect of hypoxia on fish antipredator behaviours may have major consequences for the composition of aquatic communities.

scholarly journals Adaptation to climate change: trade‐offs among responses to multiple stressors in an intertidal crustacean

2016 ◽  
Vol 9 (9) ◽  
pp. 1147-1155 ◽  
Author(s):  
Morgan W. Kelly ◽  
Melissa B. DeBiasse ◽  
Vidal A. Villela ◽  
Hope L. Roberts ◽  
Colleen F. Cecola
Keyword(s):  
Climate Change ◽  
Multiple Stressors ◽  
Adaptation To Climate Change ◽  
Trade Offs

scholarly journals Breathing space: deoxygenation of aquatic environments can drive differential ecological impacts across biological invasion stages

2021 ◽  
Author(s):  
James W. E. Dickey ◽  
Neil E. Coughlan ◽  
Jaimie T. A. Dick ◽  
Vincent Médoc ◽  
Monica McCard ◽  
...  
Keyword(s):  
Climate Change ◽  
Oxygen Saturation ◽  
Ecological Impacts ◽  
Neogobius Melanostomus ◽  
Aquatic Environments ◽  
Relative Impact ◽  
Low Oxygen ◽  
Per Capita ◽  
The Impact ◽  
Prey Populations

AbstractThe influence of climate change on the ecological impacts of invasive alien species (IAS) remains understudied, with deoxygenation of aquatic environments often-overlooked as a consequence of climate change. Here, we therefore assessed how oxygen saturation affects the ecological impact of a predatory invasive fish, the Ponto-Caspian round goby (Neogobius melanostomus), relative to a co-occurring endangered European native analogue, the bullhead (Cottus gobio) experiencing decline in the presence of the IAS. In individual trials and mesocosms, we assessed the effect of high, medium and low (90%, 60% and 30%) oxygen saturation on: (1) functional responses (FRs) of the IAS and native, i.e. per capita feeding rates; (2) the impact on prey populations exerted; and (3) how combined impacts of both fishes change over invasion stages (Pre-invasion, Arrival, Replacement, Proliferation). Both species showed Type II potentially destabilising FRs, but at low oxygen saturation, the invader had a significantly higher feeding rate than the native. Relative Impact Potential, combining fish per capita effects and population abundances, revealed that low oxygen saturation exacerbates the high relative impact of the invader. The Relative Total Impact Potential (RTIP), modelling both consumer species’ impacts on prey populations in a system, was consistently higher at low oxygen saturation and especially high during invader Proliferation. In the mesocosm experiment, low oxygen lowered RTIP where both species were present, but again the IAS retained high relative impact during Replacement and Proliferation stages at low oxygen. We also found evidence of multiple predator effects, principally antagonism. We highlight the threat posed to native communities by IAS alongside climate-related stressors, but note that solutions may be available to remedy hypoxia and potentially mitigate impacts across invasion stages.

scholarly journals Connectivity Map Analysis Indicates PI3K/Akt/mTOR Inhibitors as Potential Anti-Hypoxia Drugs in Neuroblastoma

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2809
Author(s):  
Paolo Uva ◽  
Maria Carla Bosco ◽  
Alessandra Eva ◽  
Massimo Conte ◽  
Alberto Garaventa ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Drug Repurposing ◽  
Enrichment Analysis ◽  
Mtor Inhibitors ◽  
Gene Set Enrichment Analysis ◽  
Low Oxygen ◽  
Connectivity Map ◽  
Hypoxic Conditions ◽  
Connectivity Score

Neuroblastoma (NB) is one of the deadliest pediatric cancers, accounting for 15% of deaths in childhood. Hypoxia is a condition of low oxygen tension occurring in solid tumors and has an unfavorable prognostic factor for NB. In the present study, we aimed to identify novel promising drugs for NB treatment. Connectivity Map (CMap), an online resource for drug repurposing, was used to identify connections between hypoxia-modulated genes in NB tumors and compounds. Two sets of 34 and 21 genes up- and down-regulated between hypoxic and normoxic primary NB tumors, respectively, were analyzed with CMap. The analysis reported a significant negative connectivity score across nine cell lines for 19 compounds mainly belonging to the class of PI3K/Akt/mTOR inhibitors. The gene expression profiles of NB cells cultured under hypoxic conditions and treated with the mTORC complex inhibitor PP242, referred to as the Mohlin dataset, was used to validate the CMap findings. A heat map representation of hypoxia-modulated genes in the Mohlin dataset and the gene set enrichment analysis (GSEA) showed an opposite regulation of these genes in the set of NB cells treated with the mTORC inhibitor PP242. In conclusion, our analysis identified inhibitors of the PI3K/Akt/mTOR signaling pathway as novel candidate compounds to treat NB patients with hypoxic tumors and a poor prognosis.

scholarly journals Identifying integrated options for agricultural climate change mitigation

2014 ◽  
Vol 6 (2) ◽  
pp. 192-211 ◽  
Author(s):  
John Tzilivakis ◽  
Kathleen Lewis ◽  
Andrew Green ◽  
Douglas Warner
Keyword(s):  
Climate Change ◽  
Climate Change Mitigation ◽  
Effective Means ◽  
Integrated Approach ◽  
Management Options ◽  
Content Type ◽  
Mitigation Options ◽  
Trade Offs ◽  
Environmental Objectives ◽  
Change Mitigation

Purpose – In order to achieve reductions in greenhouse gas (GHG) emissions, it is essential that all industry sectors have the appropriate knowledge and tools to contribute. This includes agriculture, which is considered to contribute about a third of emissions globally. This paper reports on one such tool: IMPACCT: Integrated Management oPtions for Agricultural Climate Change miTigation. The paper aims to discuss these issues. Design/methodology/approach – IMPACCT focuses on GHGs, carbon sequestration and associated mitigation options. However, it also attempts to include information on economic and other environmental impacts in order to provide a more holistic perspective. The model identifies mitigation options, likely economic impacts and any synergies and trade-offs with other environmental objectives. The model has been applied on 22 case study farms in seven Member States. Findings – The tool presents some useful concepts for developing carbon calculators in the future. It has highlighted that calculators need to evolve from simply calculating emissions to identifying cost-effective and integrated emissions reduction options. Practical implications – IMPACCT has potential to become an effective means of provided targeted guidance, as part of a broader knowledge transfer programme based on an integrated suite of guidance, tools and advice delivered via different media. Originality/value – IMPACCT is a new model that demonstrates how to take a more integrated approach to mitigating GHGs on farms across Europe. It is a holistic carbon calculator that presents mitigation options in the context other environmental and economic objectives in the search for more sustainable methods of food production.

Mapping vulnerability to multiple stressors: climate change and globalization in India

2004 ◽  
Vol 14 (4) ◽  
pp. 303-313 ◽  
Author(s):  
Karen O’Brien ◽  
Robin Leichenko ◽  
Ulka Kelkar ◽  
Henry Venema ◽  
Guro Aandahl ◽  
...  
Keyword(s):  
Climate Change ◽  
Multiple Stressors ◽  
Mapping Vulnerability

Efficacy Trade-Offs in Individuals’ Support for Climate Change Policies

2012 ◽  
Vol 45 (8) ◽  
pp. 935-970 ◽  
Author(s):  
Lynn D. Rosentrater ◽  
Ingrid Sælensminde ◽  
Frida Ekström ◽  
Gisela Böhm ◽  
Ann Bostrom ◽  
...  
Keyword(s):  
Climate Change ◽  
Climate Change Policies ◽  
Trade Offs
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