Predicting the Impact of Climate Change on Threatened Species in UK Waters

Global climate change is affecting the distribution of marine species and is thought to represent a threat to biodiversity. Previous studies project expansion of species range for some species and local extinction elsewhere under climate change. Such range shifts raise concern for species whose long-term persistence is already threatened by other human disturbances such as fishing. However, few studies have attempted to assess the effects of future climate change on threatened vertebrate marine species using a multi-model approach. There has also been a recent surge of interest in climate change impacts on protected areas. This study applies three species distribution models and two sets of climate model projections to explore the potential impacts of climate change on marine species by 2050. A set of species in the North Sea, including seven threatened and ten major commercial species were used as a case study. Changes in habitat suitability in selected candidate protected areas around the UK under future climatic scenarios were assessed for these species. Moreover, change in the degree of overlap between commercial and threatened species ranges was calculated as a proxy of the potential threat posed by overfishing through bycatch. The ensemble projections suggest northward shifts in species at an average rate of 27 km per decade, resulting in small average changes in range overlap between threatened and commercially exploited species. Furthermore, the adverse consequences of climate change on the habitat suitability of protected areas were projected to be small. Although the models show large variation in the predicted consequences of climate change, the multi-model approach helps identify the potential risk of increased exposure to human stressors of critically endangered species such as common skate (Dipturus batis) and angelshark (Squatina squatina)

Spatial distribution of life-history traits and their response to environmental gradients across multiple marine taxa

Trait‐based approaches enable comparison of community composition across multiple organism groups. Yet, little is known about the degree to which empirical trait responses found for one taxonomic group can be generalized across organisms. In this study, we investigated the spatial variability of marine community‐weighted mean traits and compared their environmental responses across multiple taxa and habitats, including pelagic zooplankton (copepods), demersal fish, and benthic infaunal invertebrates. We used extensive, spatially explicit datasets collected from scientific surveys in the North Sea and examined community composition of these groups using a trait‐based approach. In order to cover the key biological characteristics of an organism, we considered three life‐history traits (adult size, offspring size, and fecundity) and taxon‐specific feeding traits. While many of the traits co‐varied in space and notably demonstrated a south–north gradient, none of the traits showed a consistent spatial distribution across all groups. However, traits are often correlated as a result of trade‐offs. When studying spatial patterns of multiple traits variability in fish and copepods, we showed a high spatial correlation. This also applied to a lesser extent to fish and benthic infauna, whereas no correlation was found between benthic infauna and copepods. The result suggested a decoupling in the community traits between strictly benthic and strictly pelagic species. The strongest drivers of spatial variability for many community traits are the gradients in temperature seasonality, primary productivity, fishing effort, and depth. Spatial variability in benthic traits also co‐varied with descriptors of the seabed habitat. Overall, results showed that trait responses to environmental gradients cannot be generalized across organism groups, pointing toward potential complex responses of multi‐taxa communities to environmental changes and highlighting the need for cross‐habitat multi‐trait analyses to foresee how environmental change will affect community structure and biodiversity at large

Changing storminess and global capture fisheries

This is the author accepted manuscript. The final version is available from Nature Publishing Group via the DOI in this record.Climate change-driven alterations in storminess pose a signifcant threat to global capture fsheries. Understanding how storms interact with fshery social-ecological systems can inform adaptive action and help to reduce the vulnerability of those dependent on fisheries for life and livelihood.N.C.S. acknowledges the financial support of the UK Natural Environment Research Council (NERC; GW4+ studentship NE/L002434/1), Centre for Environment, Fisheries and Aquaculture Science and Willis Research Network

Effects of the trawling ban on demersal fish communities in the marine environment of Hong Kong, South China

Oral PresentationFisheries & Marine Resources ManagementFishery resources in Hong Kong have been over-exploited since the 1970s. In 2010, there were still around 400 trawlers operating in local waters. These trawlers nonselectively catch marine organisms of all sizes, while exerting severe physical damage to the benthic ecosystem. To mitigate the associated impacts of overfishing and trawling, the Government of the Hong Kong Special Administrative Region has imposed a territory-wide trawling ban across local marine waters since 31 December 2012. This study aims to investigate if the trawl-ban policy is effective to facilitate recovery of demersal fish resources, in terms of species diversity, abundance and biomass, in Hong Kong. Under an approved scientific permit, trawl surveys were conducted using a commercial shrimp trawler in eastern (EW), western (WW) and southern waters (SW) of Hong Kong from ...postprin

Improving understanding of the functional diversity of fisheries by exploring the influence of global catch reconstruction

Functional diversity is thought to enhance ecosystem resilience, driving research focused on trends in the functional composition of fisheries, most recently with new reconstructions of global catch data. However, there is currently little understanding of how accounting for unreported catches (e.g. small-scale and illegal fisheries, bycatch and discards) influences functional diversity trends in global fisheries. We explored how diversity estimates varied among reported and unreported components of catch in 2010, and found these components had distinct functional fingerprints. Incorporating unreported catches had little impact on global-scale functional diversity patterns. However, at smaller, management-relevant scales, the effects of incorporating unreported catches were large (changes in functional diversity of up to 46%). Our results suggest there is greater uncertainty about the risks to ecosystem integrity and resilience from current fishing patterns than previously recognized. We provide recommendations and suggest a research agenda to improve future assessments of functional diversity of global fisheries

Uncertainties in projecting climate-change impacts in marine ecosystems

Projections of the impacts of climate change on marine ecosystems are a key prerequisite for the planning of adaptation strategies, yet theyare inevitablyassociated withuncertainty.Identifying,quantifying,andcommunicatingthisuncertaintyis keytobothevaluatingtherisk associated with a projection and building confidence in its robustness. Wereview howuncertainties in such projections are handled in marine science. We employan approach developedin climatemodelling by breaking uncertainty down into(i) structural (model) uncertainty,(ii) initialization and internalvariabilityuncertainty,(iii)parametricuncertainty,and(iv)scenariouncertainty.Foreachuncertaintytype,wethenexaminethecurrent state-of-the-art in assessing and quantifying its relative importance. We consider whether the marine scientific community has addressed these types of uncertainty sufficiently and highlight the opportunities and challenges associated with doing a better job. We find that even within a relatively small field such as marine science, there are substantial differences between subdisciplines in the degree of attention given to each type of uncertainty. We find that initialization uncertainty is rarely treated explicitly and reducing this type of uncertainty may deliver gainsontheseasonal-to-decadaltime-scale.Weconcludethatallpartsofmarinesciencecouldbenefitfromagreaterexchangeofideas,particularly concerningsuchauniversalproblemsuchasthetreatmentofuncertainty.Finally,marinescienceshouldstrivetoreachthepointwherescenario uncertainty is the dominant uncertainty in our projections

Spatial variation in trophic structure of Demersal Fish Communities in the marine environment of Hong Kong, South China

Poster presentation: P-55Fisheries & Marine Resources ManagementHong Kong’s western coastal waters (WW) situated at the Pearl River Estuary are heavily influenced by freshwater and sediment discharges from the Pearl River, while its eastern waters (EW) are mainly affected by oceanic and tidal currents. The southern waters (SW) are positioned along this estuarine-oceanic salinity gradient. Such variations in hydrography and salinity drive differences in trophic structure in local marine ecosystems. This study aimed to investigate the spatial variation in trophic structure of six demersal fish communities in WW (inner and outer estuary), EW (inner and outer Tolo Channel) and SW (waters in southeast and around Lamma). Stable isotopic ratios of δ13C and δ15N of all benthic fishes caught in trawl surveys during July-September and ...postprin

Elasticity in ecosystem services: Exploring the variable relationship between ecosystems and human well-being

Although ecosystem services are increasingly recognized as benefits people obtain from nature, we still have a poor understanding of how they actually enhance multidimensional human well-being, and how well-being is affected by ecosystem change. We develop a concept of “ecosystem service elasticity” (ES elasticity) that describes the sensitivity of human well-being to changes in ecosystems. ES Elasticity is a result of complex social and ecological dynamics and is context dependent, individually variable, and likely to demonstrate nonlinear dynamics such as thresholds and hysteresis. We present a conceptual framework that unpacks the chain of causality from ecosystem stocks through flows, goods, value, and shares to contribute to the well-being of different people. This framework builds on previous conceptualizations, but places multidimensional well-being of different people as the final element. This ultimately disaggregated approach emphasizes how different people access benefits and how benefits match their needs or aspirations. Applying this framework to case studies of individual coastal ecosystem services in East Africa illustrates a wide range of social and ecological factors that can affect ES elasticity. For example, food web and habitat dynamics affect the sensitivity of different fisheries ecosystem services to ecological change. Meanwhile high cultural significance, or lack of alternatives enhance ES elasticity, while social mechanisms that prevent access can reduce elasticity. Mapping out how chains are interlinked illustrates how different types of value and the well-being of different people are linked to each other and to common ecological stocks. We suggest that examining chains for individual ecosystem services can suggest potential interventions aimed at poverty alleviation and sustainable ecosystems while mapping out of interlinkages between chains can help to identify possible ecosystem service trade-offs and winners and losers. We discuss conceptual and practical challenges of applying such a framework and conclude on its utility as a heuristic for structuring interdisciplinary analysis of ecosystem services and human wellbeing.This paper results from the project Sustainable Poverty Alleviation from Coastal Ecosystem Services (SPACES) project number NE-K010484-1, funded by the Ecosystem Services for Poverty Alleviation (ESPA) programme. The ESPA programme is funded by the Department for International Development (DFID), the Economic and Social Research Council (ESRC), and the Natural Environment Research Council (NERC).

Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios

The ocean moderates anthropogenic climate change at the cost of profound alterations of its physics, chemistry, ecology, and services. Here, we evaluate and compare the risks of impacts on marine and coastal ecosystems and the goods and services they provide for growing cumulative carbon emissions under two contrasting emissions scenarios. The current emissions trajectory would rapidly and significantly alter many ecosystems and the associated services on which humans heavily depend. A reduced emissions scenario consistent with the Copenhagen Accord’s goal of a global temperature increase of less than 2°C—is much more favorable to the ocean but still substantially alters important marine ecosystems and associated goods and services. The management options to address ocean impacts narrow as the ocean warms and acidifies. Consequently, any new climate regime that fails to minimize ocean impacts would be incomplete and inadequate