Search results for " change"

Effects of a mobile disturbance pattern on dynamic patch networks and metapopulation persistence

2021

Abstract Motivation Certain early-succession habitats may emerge only at restricted locations following disturbance. Therefore, whether disturbances tend to occur at certain sites or not can significantly affect habitat availability and metapopulation persistence of early-successional habitat specialists. Available models that combine metapopulation and landscape processes do not address how to model mobile, spatially shifting disturbance intensities independent of factors of site suitability. We present a model that allows the study on how a mobile disturbance pattern, of either natural or anthropogenic origin, affects patch network and metapopulation dynamics in realistic, heterogeneous l…

Recruitment signals in juvenile cod surveys depend on thermal growth conditions

2017

Coastal seine surveys contain some of the only direct measures of age-0 abundance for Atlantic cod (Gadus morhua) and Pacific cod (Gadus macrocephalus), yet their utility in forecasting future year-class strength has not been evaluated among regions. We analyzed coastal time series from the Gulf of Alaska, Newfoundland, and Norway to test the hypothesis that recruitment signals are stronger when assessed under thermal conditions that provide high juvenile growth potential. Weaker recruitment signals were associated with low growth potential from cold winters (Newfoundland) and recent warmer summers (Norway). We conclude that temperature-dependent growth strongly influences the utility of c…

Shift in Tuna Catches due to Ocean Warming.

2017

Ocean warming is already affecting global fisheries with an increasing dominance of catches of warmer water species at higher latitudes and lower catches of tropical and subtropical species in the tropics. Tuna distributions are highly conditioned by sea temperature, for this reason and their worldwide distribution, their populations may be a good indicator of the effect of climate change on global fisheries. This study shows the shift of tuna catches in subtropical latitudes on a global scale. From 1965 to 2011, the percentage of tropical tuna in longliner catches exhibited a significantly increasing trend in a study area that included subtropical regions of the Atlantic and western Pacifi…

Eight decades of sampling reveal a contemporary novel fish assemblage in coastal nursery habitats.

2015

In order to adequately monitor biodiversity trends through time and their responses to natural or anthropogenic impacts, researchers require long time series that are often unavailable. This general lack of datasets that are several decades or longer makes establishing a background or baseline of diversity metrics difficult - especially when attempting to understand species composition changes against a backdrop of climate and ecological variability. Here, we present an analysis of a community of juvenile nearshore fishes based on nearly 8 decades of highly standardized Norwegian survey records. Using multivariate statistical techniques, we: (i) characterize the change in taxonomic communit…

Predicting shifting sustainability trade-offs in marine finfish aquaculture under climate change

2018

Defining sustainability goals is a crucial but difficult task because it often involves the quantification of multiple interrelated and sometimes conflicting components. This complexity may be exacerbated by climate change, which will increase environmental vulnerability in aquaculture and potentially compromise the ability to meet the needs of a growing human population. Here, we developed an approach to inform sustainable aquaculture by quantifying spatio-temporal shifts in critical trade-offs between environmental costs and benefits using the time to reach the commercial size as a possible proxy of economic implications of aquaculture under climate change. Our results indicate that optim…

2020

Marine and coastal activities are closely interrelated, and conflicts among different sectors can undermine management and conservation objectives. Governance systems for fisheries, power generation, irrigation, aquaculture, marine biodiversity conservation, and other coastal and maritime activities are typically organized to manage conflicts within sectors, rather than across them. Based on the discussions around eight case studies presented at a workshop held in Brest in June 2019, this paper explores institutional approaches to move beyond managing conflicts within a sector. We primarily focus on cases where the groups and sectors involved are heterogeneous in terms of: the jurisdiction …

Genome Sequencing and Transcriptome Analysis Reveal Recent Species-Specific Gene Duplications in the Plastic Gilthead Sea Bream (Sparus aurata)

2019

Gilthead sea bream is an economically important fish species that is remarkably well-adapted to farming and changing environments. Understanding the genomic basis of this plasticity will serve to orientate domestication and selective breeding toward more robust and efficient fish. To address this goal, a draft genome assembly was reconstructed combining short- and long-read high-throughput sequencing with genetic linkage maps. The assembled unmasked genome spans 1.24 Gb of an expected 1.59 Gb genome size with 932 scaffolds (~732 Mb) anchored to 24 chromosomes that are available as a karyotype browser at www.nutrigroup-iats.org/seabreamdb. Homology-based functional annotation, supported by R…

Global functional variation in alpine vegetation

2021

International audience; Questions. What are the functional trade-offs of vascular plant species in global alpine ecosystems? How is functional variation related to vegetation zones, climatic groups and biogeographic realms? What is the relative contribution of macroclimate and evolutionary history in shaping the functional variation of alpine plant communities? Location. Global. Methods. We compiled a data set of alpine vegetation with 5,532 geo-referenced plots, 1,933 species and six plant functional traits. We used principal component analysis to quantify functional trade-offs among species and trait probability density to assess the functional dissimilarity of alpine vegetation in differ…

Disjunct populations of European vascular plant species keep the same climatic niches

2015

Aim Previous research on how climatic niches vary across species ranges has focused on a limited number of species, mostly invasive, and has not, to date, been very conclusive. Here we assess the d ...

Increasing water temperature and disease risks in aquatic systems: Climate change increases the risk of some, but not all, diseases

2010

Global warming may impose severe risks for aquatic animal health if increasing water temperature leads to an increase in the incidence of parasitic diseases. Essentially, this could take place through a temperature-driven effect on the epidemiology of the disease. For example, higher temperature may boost the rate of disease spread through positive effects on parasite fitness in a weakened host. Increased temperature may also lengthen the transmission season leading to higher total prevalence of infection and more widespread epidemics. However, to date, general understanding of these relationships is limited due to scarcity of long-term empirical data. Here, we present one of the first long…