The future of fishes and fisheries in the changing oceans: FISHES AND FISHERIES IN THE CHANGING OCEANS

Abstract

This paper aims to highlight the risk of climate change on coupled marine human and natural systems and explore possible solutions to reduce such risk. Specifically, it explores some of the key responses of marine fish stocks and fisheries to climate change and their implications for human society. It highlights the importance of mitigating carbon emission and achieving the Paris Agreement in reducing climate risk on marine fish stocks and fisheries. Finally, it discusses potential opportunities for helping fisheries to reduce climate threats, through local adaptation. A research direction in fish biology and ecology is proposed that would help support the development of these potential solutions.

Full text

Journal of Fish Biology (2018) 92, 790–803
doi:10.1111/jfb.13558, available online at wileyonlinelibrary.com
The future of shes and sheries in the changing oceans
W. W. L. C*
Changing Ocean Research Unit, Institute for the Oceans and Fisheries, The University of
British Columbia, Vancouver, BC, V6T 1Z4, Canada
This paper aims to highlight the risk of climate change on coupled marine human and natural systems
and explore possible solutions to reduce such risk. Specically, it explores some of the key responses of
marine sh stocks and sheries to climate change and their implications for human society. It highlights
the importance of mitigating carbon emission and achieving the Paris Agreement in reducing climate
risk on marine sh stocks and sheries. Finally, it discusses potential opportunities for helping sheries
to reduce climate threats, through local adaptation. A research direction in sh biology and ecology is
proposed that would help support the development of these potential solutions.
© 2018 The Fisheries Society of the British Isles
Key words: adaptation scenarios; climate change; sheries; shes; mitigation; vulnerability.
THE GLOBAL OCEAN CHALLENGE
Global change, i.e. planetary-scale changes in the Earth system, is challenging the sus-
tainability of marine sh stocks and sheries (Pörtner et al., 2014; Gattuso et al., 2015).
The main direct global change drivers in the oceans include overshing, pollution, habi-
tat destruction and climate change, which includes ocean acidication (Halpern et al.,
2012; Pitcher & Cheung, 2013). Based on sheries and mariculture production data,
total global seafood production has stabilized since the mid-1990s (Fig. 1; Campbell
& Pauly, 2013; Pauly & Zeller, 2016; www.searoundus.org). Specically, capture sh-
eries production decreased during this period while the expansion of the mariculture
sector, particularly in China, lled the gap. The catch-per-unit-effort, however, a proxy
of sheries resource abundance, has approximately halved since the 1950s (Watson
et al., 2013), with over 60% of the global sh stocks that have biomass below those
that are expected to produce maximum sustainable yield (Worm et al., 2009; Costello
et al., 2012). Continuing shing as the status quo will result in further depletion and
erosion of societal benets from sh stocks (Sumaila et al., 2007; Costello et al., 2016).
While effective reduction and management of shing effort can rebuild sh stocks
to sustainable levels (Worm et al., 2009; Sumaila et al., 2012; Costello et al., 2016),
climate change poses fundamental challenge to such measures (Cheung et al., 2012).
Particularly, in addition to the top-down effect of shing, bottom-up environmental
factors such as temperature and primary production also play a signicant role in
determining global sh stock production (McOwen et al., 2015; Britten et al., 2016).
*Author to whom correspondence should be addressed. Tel.: +1 604 827 3756; email:
w.cheung@oceans.ubc.ca
790
© 2018 The Fisheries Society of the British Isles

FISHES AND FISHERIES IN THE CHANGING OCEANS 791
Annual production (Mt)
140
120
100
80
60
40
20
0
1951 1960 1970 1980 1990 2000 2010
Year
Fish
(capture)
Invertebrates
(capture)
Invertebrates
(culture)
Fish (culture)
F. 1. Global seafood production from capture sheries and mariculture (www.seaaroundus.org).
Bottom-up environmental factors are changing under climate change, consequently
affecting sh stocks and sheries production. The oceans absorb approximately 28%
of the CO2emitted from human activities and more than 90% of the added heat since
the 19th century; as a result, ocean variables that are important for sh stocks are
changing (Gattuso et al., 2015). In particular, sea-surface temperature has increased
on average by 0.07∘C decade−1during the 20th century and ocean pH decreased by
0·1 since the industrial revolution (Stocker et al., 2013), while oxygen content has
decreased by more than 2% since 1960 (Schmidtko et al., 2017). These changes are
projected to continue under the business-as-usual (Representative Concentration Path-
way or RCP 8·5; IPCC; www.sedac.ipcc-data.org/ddc/ar5_scenario_process/RCPs
.html) greenhouse gases emission scenario while the changes will be substantially
lowered under the strong-mitigation (RCP 2·6) scenario (Gattuso et al., 2015).
Climate change is challenging marine systems at multiple levels of organization
(Fig. 2). Changes in ocean conditions directly affect the physiology and biology of
marine organisms, affecting, for example, their growth, reproduction, mortality and,
thus, population dynamics. Such changes result in further shifts in the biogeogra-
phy, community structure and trophic interactions of marine ecosystems. Marine
ecosystem-dependent sectors such as capture sheries would be affected through the
effects on catches, revenues, costs as well as the effectiveness of sheries management.
These changes interact with broader global issues such as population growth, changes
in food supply, consumption patterns and energy policies. To fully understand the
challenges of climate change on marine systems and to identify opportunities to
mitigate them, holistic examination of the effects of climate change on the different
organization levels of the system is needed.
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

792 W. W. L. CHEUNG
Physical
Ocean-atmosphere changes
Biological
Human population growth,
migration, development, global food
supply and energy price
Changes in sheries catch,
economics of shing,
sheries management
Changes in community
structure, trophic
interaction, biodiversity
Changes in population
growth, abundance,
species distribution
Social/Economics
Change in body size,
reproduction,
primary productivity,
habitats
Clouds
Sun
Aerosols
AerosolsWater Vapor
Organisms Population
Community/
ecosystems
Fisheries
economics
Global
issues
Carbon Dioxide
Biological
Pump
Phytoplankton
Organic Carbon
F. 2. Conceptual diagram of multi-level responses of coupled marine natural and human systems to climate
change. The arrows indicate drivers of changes in different levels of organization of marine-coupled human
and natural systems.
This paper highlights the importance of climate change on coupled marine human
and natural systems and to explore possible solutions to reduce such risk. Specically,
it explores some of the key responses of marine sh stocks and sheries to climate
change and their implications for human society. The importance of mitigating carbon
emission and achieving the Paris Agreement (www.unfccc.int/paris_agreement/items/
9485.php) in reducing climate risk on marine sh stocks and sheries is highlighted.
Finally, some potential opportunities for helping sheries to reduce climate risk through
adaptation are discussed.
SHIFTS IN BIOGEOGRAPHY AND IMPACTS ON FISHERIES
The biogeography of marine ectotherms, including all shes and invertebrates, is
highly dependent on ocean conditions, particularly temperature. Fishes and inverte-
brates have evolved specic temperature preference and tolerances to adapt to the
mean and variations of the environmental conditions of their habitats (Pörtner & Far-
rell, 2008). Species can respond to ocean warming partly by shifting their habitats
to areas where temperature and other ocean conditions match with their preference
and tolerance limits. Such shifts are generally towards higher latitude regions or into
deeper waters where cooler refuges exist under ocean warming (Cheung et al., 2009;
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

FISHES AND FISHERIES IN THE CHANGING OCEANS 793
Poloczanska et al., 2013). As a result, species’ ranges shift under climate change, caus-
ing changes in species composition and community structure.
Shifts in species’ biogeography have already been detected in historical catches.
Particularly, global analysis of sheries catch data using an index called the mean
temperature of catch (MTC), calculated from the average preferred temperature of
each exploited species weighted by their annual catches, have been increasing at a
rate of 0.19∘C decade−1between 1970 and 2010 (Cheung et al., 2013c). Such change
in MTC suggests that sheries have been increasingly catching more warmer-water
preferred species. For example, within the U.K. 200 mile Exclusive Economic Zone,
MTC increased at a rate of 0·51∘C decade−1from 1970 to 2014, while sea surface
temperature increased at 0·21∘C decade−1during the same period. Fishers in the U.K.
also reported themselves to have caught more warm-water associated species in recent
years, more typically distributed in southern European waters (Cheung et al., 2012).
Range shifts and changes in species composition are projected to continue in the 21st
century, resulting in species gains and losses in different regions. In the last decade,
computer simulation models have been developed to project scenarios of future distri-
bution of exploited marine species under climate change. A mechanistic species distri-
bution models (called the dynamic bioclimate envelope model, DBEM) that integrated
changes in ocean conditions, ecophysiology, spatial population dynamics with habitat
suitability modelling was developed to project annual changes in potential abundance
and sheries catches of over 1000 exploited shes and invertebrates in the global oceans
(Cheung et al., 2011, 2016b). The projections suggest that species generally shifted
poleward and into deeper water globally, leading to a high rate of species gains in the
Arctic but high local species loss in the tropical regions as well as in semi-enclosed
seas (Cheung et al., 2009; Jones & Cheung, 2015). The intensity of shift in community
structure is almost doubled under the business-as-usual RCP 8·5 scenario relative to the
strong-mitigation RCP 2·6 scenario in the mid-21st century (Jones & Cheung, 2015).
As a result, MTC of the sheries is expected to continue to increase in extra-tropical
regions (Cheung et al., 2015). In equatorial zones, MTC increased initially and then
levelled off because the remaining community is composed of species that have sta-
ble, high temperature tolerance (Cheung et al., 2013c). However, as tropical oceans
are projected to change to conditions that are beyond those that sh communities have
experienced historically, tropical sh communities are projected to have high rate of
local extinction.
In addition to species’ biogeography, another important factor determining potential
sheries catch is primary production. Marine net primary production is projected to
decrease with variations between ocean regions. Combining with shifts in distribution
of exploited species under climate change, global sheries catches are projected
to redistribute with winners and losers. Meta-analysis of historical catch data of
different species and large marine ecosystems suggest that phytoplankton composi-
tion (small and large size), net primary production or mesozooplankton production,
pelagic to demersal export production and species’ range are statistically signicant
predictors of maximum catch potential (a proxy of maximum sustainable yield)
(Cheung et al., 2008; Stock et al., 2017). Applying these principles in the DBEM
to project climate-change effects on sheries, it was found that maximum catch
potential would be redistributed, with increase in catch potential in the Arctic and
decrease in most tropical sheries under business-as-usual (Fig. 3; Cheung et al., 2010,
2016a).
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

794 W. W. L. CHEUNG
Differences in MCP
between RCP 8.5
and RCP 2.6 (%)
10
5
0
–15
–10
–20
–30
F. 3. The differences in projection of future changes in maximum catch potential (MCP) by exclusive economic
zones between the business-as-usual greenhouse gases emission scenario (representative concentration
pathway, RCP, 8·5) and strong-mitigation scenario (RCP 2·6) by the 2050s relative to the 2000s (redrawn
from Lam et al., 2016b).
Ocean acidication may further reduce the productivity of many marine sh and
invertebrate stocks, although the biological sensitivity to ocean acidication appears to
vary across taxonomic groups and life history stages. Experiments on marine species
in potential future CO2conditions suggest that ocean acidication can increase mor-
tality and reduce growth and reproductive successes of marine species, particularly
for calcifying invertebrates (Kroeker et al., 2013). Such negative effects are found in
experiments across taxonomic groups, although they are more likely to be observed in
corals, molluscs, echinoderms and larval shes than crustaceans (Wittmann & Pörtner,
2013). Sensitivity to ocean acidication also varies between species within taxonomic
group and may be exacerbated by warming. Incorporation of the potential biological
effects of ocean acidication is projected to exacerbate effects of climate change in
reducing potential catches (Cheung et al., 2011; Lam et al., 2016a). In addition, ocean
acidication has affected some shellsh aquaculture production, e.g. increased mortal-
ity of Pacic oyster (Crassostrea gigas) larvae in hatchery facilities on the west coast
of the U.S.A. (Barton et al., 2012). Ocean acidication is also projected to have large
economic implications for shellsh production in Europe in the 21st century under
business-as-usual (Narita & Rehdanz, 2017). However, the overall projected effects
depend on the assumed sensitivities of the organisms to different levels of ocean acidi-
cation, the effects of changes in other ocean conditions, as well as the potential indirect
effects through changes in trophic interactions.
Marine shes are expected to reduce in maximum body size under ocean warm-
ing and deoxygenation (Cheung et al., 2013b). The growth of marine shes is limited
by oxygen supply, with the gill surface area available for gaseous exchange being a
fundamental constraint for sh to obtain oxygen from seawater. Based on this ‘gill and
oxygen limited theory’ (Pauly & Cheung, 2017), a mathematical model was developed
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

FISHES AND FISHERIES IN THE CHANGING OCEANS 795
to predict the expected decrease in maximum body size of marine shes in the future.
The model is based on the von Bertalanffy growth model (von Bertalanffy, 1938) with
temperature-dependent metabolic terms represented by Arrhenius equations. Thus, as
temperature increases, oxygen demand to support metabolism of sh increases but oxy-
gen supply is limited by the dimensional constraints of the gill. Consequently, sh are
expected to have smaller maximum body size under warming. With more realistic scal-
ing exponents of mass-specic oxygen supply, maximum body mass is projected to
decrease on average across 754 species of exploited marine shes by 29% oC−1warm-
ing of the habitat’s water temperature. Such projected decreases in body size agree with
observed changes under warming (Cheung et al., 2013a; Baudron et al., 2014).
Other non-climatic stressors may add to or exacerbate the consequences of climate
change on marine sh stocks and sheries. Particularly, shing reduces adult popula-
tion size and, under high shing intensity, may hamper the reproductive potential of
sh populations and lead to recruitment overshing. Historical decreases in sh recruit-
ment since the 1950s are attributable to warming, decrease in primary production, as
well as shing effects (Britten et al., 2016). Reduction of long-lived and slow-growing
shes and increased in dominance of short-lived, fast-growing species by shing, as
evidenced in most places, will also increase the sensitivity of the communities to cli-
mate change (Perry et al., 2010). Moreover, shing alters trophic interactions that may
have idiosyncratic effects on species’ range shifts under warming (Ainsworth et al.,
2011; Bates et al., 2017). In addition, pollution, including eutrophication, persistent
organic pollutants and heavy metal, e.g. mercury bioaccumulation, may exacerbate
sh’s exposure to climate hazards and increase their biological sensitivity to climate
change (Alava et al., 2017).
IMPLICATIONS FOR ECONOMICS AND FOOD SECURITY
Consequences of climate change on sheries catches affect the economic benets and
food security of coastal communities. The projections from DBEM have been applied
to examine the implications of climate change on the revenue of sheries (Lam et al.,
2016b). The projected decrease in global sheries revenues is found to be 35% more
than the projected decrease in catches by the 2050s under the business-as-usual emis-
sion scenario. The difference in sensitivity is because of the larger decrease in potential
catches of some of the higher value species relative to the low-price species. More-
over, countries that are nutritionally vulnerable to shortage of seafood supply because
of their high dependence on sh as a source of micro-nutrients are identied (Golden
et al., 2016). The highly vulnerable countries, such as those in West Africa, overlap
with areas where potential catches are projected to decrease most intensively.
Furthermore, climate change effects can also affect vulnerable communities in tem-
perate and high latitude countries, such as the coastal First Nations in British Columbia,
Canada. Coastal First Nations people are sensitive to climate change effects on marine
species because of their strong dependence on seafood (Cisneros-Montemayor et al.,
2016). Specically, species that are currently important as they serve as food and cer-
emonial purposes for coastal First Nations, such as salmons (Oncorhynchus spp.) and
Pacic herring Clupea pallasii Velenciennes 1847, are projected to decrease largely
by up to 50% under the business-as-usual scenario (Fig. 4; Weatherdon et al., 2016).
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

796 W. W. L. CHEUNG
These ndings highlight the linkages of biological and ecological perturbations on sh
stocks and sheries on the shing sectors and society.
EXPLORING GLOBAL AND LOCAL SOLUTION OPTIONS
Given the multi-level consequences of climate change on marine systems, options to
tackle such challenges are also multi-dimensional and can be subdivided into mitigation
(global) and adaptation (local). The Paris Agreement under the United Nations Frame-
work Convention on Climate Change (www.legal.un.org/avl/ha/ccc/ccc.html) set the
goal of limiting global atmospheric warming to below 2∘C and aims for 1.5∘C rel-
ative to pre-industrial level. Achieving such a target would benet marine sheries
through reducing climatic effects on species distribution and potential catches (Che-
ung et al., 2016a). Globally, the benets in risk reduction are projected to be 6·7%,
3·4 Mt. and 24·9%∘C−1reduction in atmospheric warming in terms of reduction in
changes in species turnover, maximum catch potential loss and shrinking of body size,
respectively. Mitigation of carbon emission to achieve the global warming goal would
be most effective in obtaining these benets.
Local adaptation measures can help reduce climate risk on marine sh stocks and
sheries, although their effectiveness reduces with increasing level of climate change
(Gattuso et al., 2015). Adaptation may target climatic effects at different level of orga-
nization of marine systems (Fig. 5). The natural capacity of marine systems to adapt
to climate change varies according to their inherent characteristics and properties and
the level of exposure to climatic stressors. Such capacities can be predicted based on
existing biological and ecological theories and constraints, including evolution, oxy-
gen and capacity limitation, macro-ecology and bio-economic theories. For example,
populations or species that exhibit higher diversity of inheritable traits that relate to
their particular tolerance to the changing ocean conditions, or with higher turnover
rate, confer higher rate of evolutionary adaptation (Aitken et al., 2008; Munday et al.,
2013). On the other hand, populations with higher mobility may also be more adaptive
as they can respond rapidly to climate change by moving into refugia with suitable
environmental conditions (Miller et al., 2017). At the community level, higher bio-
diversity (species or functional) may help maintain key ecosystem functions under
climate change. For human communities, more livelihood opportunities, human capital
and higher education level may enhance their adaptive capacity to the results of climate
change. Therefore, it is expected that the degree of climate-risk reduction through adap-
tation will predictably vary between species, systems, regions and the implementation
of human interventions.
Adaptation of marine systems can be enhanced by human interventions. These inter-
ventions are generally based on four principles: reducing climate drivers locally; limit-
ing non-climate human drivers to reduce sensitivity of marine species– ecosystems to
climate change; supporting diversity to facilitate adaptation to environmental change;
facilitating migration and movement to areas with suitable environmental conditions
to maintain their viability (see Table I for examples of the interventions). It is expected
that these interventions can help moderate the effects of climate change and enhance
resilience on marine ecosystems.
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

FISHES AND FISHERIES IN THE CHANGING OCEANS 797
–36%
–12%
Pacic herring
–17%
–29%
–49%
–28%
Salmon Green sea
urchin
–7% –13%
Pacic
halibut
–8% –18%
Shrimp &
Prawns
–2% –7%
Rocksh
–20%
–30%
Flounder &
soles
–1·4% –2·3%
Intertidal
clams
Tsimshian
First Nations
–4% –5%
Haida Nation
–5·8% –6·6%
Heiltsuk
First Nation
–6·6% –7·9%
'Namgis
First Nation
–8·2%
–7·9%
Tla'amin
First Nation
Maa-nulth
First Nations
–28% –26%
–21% –22%
Tsawwassen
First Nation
–27%
–15%
F. 4. Projected effects of climate change [ , low emission scenario =0·5∘C rise in sea surface temperature (SST) in the north-east Pacic Ocean (under representative concentra-
tion pathway (RCP) 2·6; , high emission scenario =1.0∘C rise in SST under RCP 8·5] on species that are important for food and ceremonial purposes for coastal First Nations
in British Columbia, Canada. First Nations located along BC’s southern coastline are likely to face greater declines in the availability of traditionally targeted marine species
as these species shift northwards. Pacic herring, Clupea pallasii; salmon, Oncorhynchus tshawystcha,O. keta,O. kisutch,O. gorbuscha and O. nerka; green sea urchin,
Strongylocentrotus droebachiensis; Pacic halibut Hippoglossoides elassodon; shrimp & prawns, Pandalus platyceros,P. hypsinotus,P. borealis,P. goniurus and P. dispar;
rocksh, Sebastes spp.; ounder & soles, Atheresthes stomias,Parophrys vetulus,Hippoglossoides elassodon,Eopsetta jordani,Glytocephalus zachirus,Lepidopsetta bilin-
eata,Platichthys stellatus and Limanda aspera; intertidal clams, Venerupis philippinarum,Protothaca staminea,Saxidomus gigantea,Nuttallia obscurata. (After Weatherdon
et al., 2016.)
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

798 W. W. L. CHEUNG
Evolution;
acclimation;
movement;
behaviour
Shifts in range
and phenology
Shifts in trophic or
interspecic interactions
Relocation, changes in practice,
livelihood
Changes in policy, institution, legal
framework, economic incentives,
value norm
Individual Population CommunityHuman
(individual)
Human
(societal)
Fitness
Viability
Trophodynamic
balance
Security (income,
food, etc)
Sustainable
development
Adaptation responses
Adaptation targets
F. 5. Conceptual diagram of multi-level adaptation responses of coupled-marine natural and human system to
climate change.
Based on this theoretical framework for characterizing multi-level adaptation, it is
possible to propose a research agenda that can be used to generate a number of hypothe-
ses that help understand the future sustainability of marine ecosystems under global
change. The proposed research program aims to explore these hypotheses: hypothe-
sis 1, adaptive capacity (ability to adapt) of exploited marine species, ecosystems and
sheries is related to their intrinsic traits and characteristics; hypothesis 2, adaptive
capacity varies predictably between species, ecosystems, sheries and regions; hypoth-
esis 3, adaptation contributes substantially to reducing the effects of climate change
on marine biodiversity and functions; hypothesis 4, human interventions can enhance
adaptations of marine ecosystems to climate change; hypothesis 5 adaptation inter-
ventions may result in trade-offs and collateral consequences in managing exploited
marine species and ecosystems for ocean sustainability. This set of hypotheses can
provide a guide to develop future agenda to inform ways to boost the adaptive capacity
of coupled marine natural and human systems to climate change.
The combination of interdisciplinary databases with analytical and modelling
approaches would help us identify pathways to boost adaptation of marine systems
to climate change. For example, based on life history and evolutionary theories, the
capacity of marine species to adapt to climate change is expected to be predictable
according to biological and ecological traits. Jones & Cheung (2017) reviewed
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

FISHES AND FISHERIES IN THE CHANGING OCEANS 799
T I. Examples of human interventions to boost adaptation of marine systems
Intervention Description
Protection Reduce or remove other stressors (climate and non-climate) from
natural systems to increase the capacity of the species or
ecosystems to respond to climate change, i.e. to enhance resilience
Restoration Restoration of populations or habitats to moderate sensitivity to
climate stressors, e.g. restoration of coastal vegetation
Translocation Proactive relocation of species or habitats to areas with suitable
environmental conditions
Assisted evolution Increasing the rate of evolution through, e.g., selective breeding and
pre-conditioning of individuals to changed environmental
conditions
published literature and identied life history and ecological variables that are related
to the adaptive capacity of exploited marine species to climate change. Analysing
global databases of biological and ecological traits of marine shes and inverte-
brates with a fuzzy-logic expert system, an index was computed of adaptive capacity
(IAC), vulnerability (sensitivity +adaptive capacity) and risk of perturbations (vul-
nerability and exposure to climate hazard) for >1000 exploited marine shes and
invertebrates (Fig. 6; see Jones & Cheung, 2017 for details of the methodology).
Although the exploited marine species has an average of moderate adaptive capacity
(mean IAC =41), over 30% of the species have low to very low adaptive capacity to
climatic effects. With the high exposure to climate hazard under the business-as-usual
greenhouse gas emission scenario, most species are expected to have high to very high
risk of climatic effects (Fig. 6). Such an index can help the identication of particular
species, communities or sheries that are less adaptive and more vulnerable to climatic
effects, based on which ways to boost their adaptive capacity can be further evaluated.
Another example is the use of DBEM to explore sheries management scenarios in
the high seas that could help reduce the consequences of climate change on straddling
sh stocks and their catches by sheries operating within national jurisdictions (Che-
ung et al., 2017). Specically, the model results suggest that scenarios with effective
sheries management or closing the high seas completely would increase sh biomass
that would spill-over into coastal regions. Globally, this would be able to compensate
for the loss in sheries catch under a lower climate change scenario while such man-
agement measures will not be sufciently effective in minimizing climate risks under
the high emission scenario. The result highlights that reducing other human pressures
such as overshing can contribute to climate adaptation for enhancing sh stocks and
sheries.
TOWARDS INTERDISCIPLINARY AND INTEGRATIVE SCIENCE
Given the large perturbations observed and predicted for marine systems from cli-
mate change, there is an urgent need to develop scientic knowledge that can accel-
erate the development, selection and implementation of ocean-related mitigation and
management policies. Because of the multi-level nature of climatic effects and their
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

800 W. W. L. CHEUNG
100
75
50
25
0
Adaptivity (lack of) VulnerabilityRisk of perturbations
IAC
F. 6. Predicted index of adaptive capacity (IAC)), vulnerability and risk of climatic effects of 1074 exploited
marine shes and invertebrates globally using the fuzzy-logic expert system developed by Jones & Cheung
(2017). Index value: 100 =lowest adaptive capacity, highest vulnerability and risk of perturbations from
climate change.
potential solutions, it is envisaged that there will be high demand for marine and sh-
eries science studies that are interdisciplinary and consider the linkages and interactions
between different levels of organization of the marine ecosystems (Fig. 1). Such col-
laborations could be facilitated by creation of open-data infrastructure to share experi-
mental and observational data and model outputs that are linked and harmonized. Such
infrastructure will support the development of analytical algorithms that would help
generate hypotheses, test theories and develop projections of the consequences for
marine natural and human systems from climate change as well as facilitate the evalu-
ation of effectiveness of different potential solution options. In addition, platforms are
needed at international, regional and local levels to allow researchers, as well as the
stakeholders of the oceans, to communicate and discuss research ideas and ndings that
would facilitate the transfer and mobilization of new knowledge to develop policy and
management measures to tackle the global change challenge for ocean sustainability.
This paper is based on a keynote presentation given during the 50th Anniversary meeting
of The Fisheries Society of the British Isles (FSBI) at the University of Exeter, U.K., in July
2017. I am grateful to FSBI for inviting and providing nancial support for me to attend this
meeting. I acknowledge funding support from the Nippon Foundation-UBC Nereus Program
and the Natural Sciences and Engineering Research Council of Canada.
References
Ainsworth, C. H., Samhouri, J. F., Busch, D. S., Cheung, W. W. L., Dunne, J. & Okey, T. A.
(2011). Potential impacts of climate change on northeast Pacic marine foodwebs and
sheries. ICES Journal of Marine Science 68,1217– 1229.
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

FISHES AND FISHERIES IN THE CHANGING OCEANS 801
Aitken, S. N., Yeaman, S., Holliday, J. A., Wang, T. & Curtis-McLane, S. (2008). Adaptation,
migration or extirpation: climate change outcomes for tree populations. Evolutionary
Applications 1, 95–111.
Alava, J. J., Cheung, W. W. L., Ross, P. S. & Sumaila, U. R. (2017). Climate change
–contaminant interactions in marine food webs: toward a conceptual framework. Global
Change Biology 23, 3984– 4001.
Barton, A., Hales, B., Waldbusser, G. G., Langdon, C. & Feely, R. A. (2012). The Pacic oyster,
Crassostrea gigas, shows negative correlation to naturally elevated carbon dioxide levels:
implications for near-term ocean acidication effects. Limnology and Oceanography 57,
698–710. https://doi.org/10.4319/lo.2012.57.3.0698
Bates, A. E., Stuart-Smith, R. D., Barrett, N. S. & Edgar, G. J. (2017). Biological interactions
both facilitate and resist climate-related functional change in temperate reef communities.
Proceedings of the Roayal Society B 284, 20170484. https://doi.org/10.1098/rspb.2017
.0484
Baudron, A. R., Needle, C. L., Rijnsdorp, A. D. & Tara Marshall, C. (2014). Warming tempera-
tures and smaller body sizes: synchronous changes in growth of North Sea shes. Global
Change Biology 20, 1023– 1031.
von Bertalanffy, L. (1938). A quantitative theory of organic growth (inquiries on growth lawsII).
Human Biology 10, 181–213.
Britten, G. L., Dowd, M. & Worm, B. (2016). Changing recruitment capacity in global sh
stocks. Proceedings of the National Academy of Sciences f the U.S.A 113, 134–139.
Campbell, B. & Pauly, D. (2013). Mariculture: a global analysis of production trends since 1950.
Marine Policy 39, 94–100.
Cheung, W. W. L., Close, C., Lam, V., Watson, R. & Pauly, D. (2008). Application of macroe-
cological theory to predict effects of climate change on global sheries potential. Marine
Ecology Progress Series 365, 187 – 197.
Cheung, W. W. L., Lam, V. W. Y., Sarmiento, J. L., Kearney, K., Watson, R. & Pauly, D. (2009).
Projecting global marine biodiversity impacts under climate change scenarios. Fish and
Fisher ies 10, 235–251.
Cheung, W. W. L., Lam, V. W. Y., Sarmiento, J. L., Kearney, K., Watson, R. E. G., Zeller, D. &
Pauly, D. (2010). Large-scale redistribution of maximum sheries catch potential in the
global ocean under climate change. Global Change Biology 16, 24–35.
Cheung, W. W. L., Dunne, J., Sarmiento, J. L. & Pauly, D. (2011). Integrating ecophysiology
and plankton dynamics into projected maximum sheries catch potential under climate
change in the northeast Atlantic. ICES Journal of Marine Science 68,1008– 1018.
Cheung, W. W. L., Pinnegar, J., Merino, G., Jones, M. C. & Barange, M. (2012). Review of
climate change impacts on marine sheries in the UK and Ireland. Aquatic Conservation:
Marine and Freshwater Ecosystems 22, 368–388.
Cheung, W. W. L., Pauly, D. & Sarmiento, J. L. (2013a). How to make progress in projecting
climate change impacts. ICES Journal of Marine Science 70, 1069– 1074.
Cheung, W. W. L., Sarmiento, J. L., Dunne, J., Frölicher, T. L., Lam, V. W. Y., Palomares, M. L.
D., Watson, R. & Pauly, D. (2013b). Shrinking of shes exacerbates impacts of Global
Ocean changes on marine ecosystems. Nature Climate Change 3, 254– 258.
Cheung, W. W. L., Watson, R. & Pauly, D. (2013c). Signature of ocean warming in global
sheries catch. Nature 497, 365– 368.
Cheung, W. W. L., Brodeur, R. D., Okey, T. A. & Pauly, D. (2015). Projecting future changes in
distributions of pelagic sh species of northeast Pacic shelf seas. Progress in Oceanog-
raphy 130, 19– 31.
Cheung, W. W. L., Reygondeau, G. & Frölicher, T. L. (2016a). Large benets to marine sheries
of meeting the 1.5 c global warming target. Science 354, 1591– 1594.
Cheung, W. W. L., Jones, M. C., Reygondeau, G., Stock, C. A., Lam, V.W.Y.&Frölicher,
T. L. (2016b). Structural uncertainty in projecting global sheries catches under climate
change. Ecological Modelling 325, 57–66.
Cheung, W. W. L., Jones, M. C., Lam, V. W. Y., D Miller, D., Ota, Y., Teh, L. & Sumaila, U. R.
(2017). Transform high seas management to build climate resilience in marine seafood
supply. Fish and Fi sheries 18,254 – 263.
Cisneros-Montemayor, A. M., Pauly, D., Weatherdon, L. V. & Ota, Y. (2016). A global estimate
of seafood consumption by coastal indigenous peoples. PLoS One 11, e0166681.
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

802 W. W. L. CHEUNG
Costello, C., Ovando, D., Hilborn, R., Gaines, S. D., Deschenes, O. & Lester, S. E. (2012).
Status and solutions for the world’s unassessed sheries. Science 338,517– 520.
Costello, C., Ovando, D., Clavelle, T., Strauss, C. K., Hilborn, R., Melnychuk, M. C., Branch,
T. A., Gaines, S. D., Szuwalski, C. S., Cabral, R. B., Rader, D. N. & Leland, A. (2016).
Global shery prospects under contrasting management regimes. Proceedings of the
National Academy of Sciences of the U.S.A. 113, 5125– 5129.
Gattuso, J.-P., Magnan, A., Billé, R., Cheung, W. W. L., Howes, E. L., Joos, F., Allemand, D.,
Bopp, L., Cooley, S. R. & Eakin, C. M. (2015). Contrasting futures for ocean and society
from different anthropogenic CO2emissions scenarios. Science 349, aac4722.
Golden, C. D., Allison, E. H., Cheung, W. W. L., Dey, M. M., Halpern, B. S., McCauley, D. J.,
Smith, M., Vaitla, B., Zeller, D. & Myers, S. S. (2016). Fall in sh catch threatens human
health. Nature 534, 317– 320.
Halpern, B. S., Longo, C., Hardy, D., McLeod, K. L., Samhouri, J. F., Katona, S. K., Kleisner,
K., Lester, S. E., O’Leary, J. & Ranelletti, M. (2012). An index to assess the health and
benets of the global ocean. Nature 488,615– 620.
Jones, M. C. & Cheung, W. W. L. (2015). Multi-model ensemble projections of climate change
effects on global marine biodiversity. ICES Journal of Marine Science 72, 741–752.
Jones, M. & Cheung, W. W. L. (2017). Using fuzzy logic to determine the vulnerability of marine
species to climate change. Global Change Biology (Online). https://doi.org/10.1111/gcb
.13869
Kroeker, K. J., Kordas, R. L., Crim, R., Hendriks, I. E., Ramajo, L., Singh, G. S., Duarte, C. M.
& Gattuso, J.-P. (2013). Impacts of ocean acidication on marine organisms: quantifying
sensitivities and interaction with warming. Global Change Biology 19, 1884– 1896.
Lam, V. W. Y., Cheung, W. W. L. & Sumaila, U. R. (2016a). Marine capture sheries in the Arc-
tic: winners or losers under climate change and ocean acidication? Fish and Fi sheries
17, 335–357.
Lam, V. W. Y., Cheung, W. W. L., Reygondeau, G. & Sumaila, U. R. (2016b). Projected change
in global sheries revenues under climate change. Scientic Reports 6. https://doi.org/
10.1038/srep32607
McOwen, C. J., Cheung, W. W. L., Rykaczewski, R. R., Watson, R. A. & Wood, L. J. (2015).
Is sheries production within large marine ecosystems determined by bottom-up or
top-down forcing? Fish and Fisheries 16, 623 – 632.
Miller, D. D., Ota, Y., Sumaila, U. R., Cisneros-Montemayor, A. M. & Cheung, W. W. L. (2017).
Adaptation strategies to climate change in marine systems. Global Change Biology 24,
e1–14.
Munday, P. L., Warner, R. R., Monro, K., Pandol, J. M. & Marshall, D. J. (2013). Predicting
evolutionary responses to climate change in the sea. Ecology Letters 16, 1488–1500.
Narita, D. & Rehdanz, K. (2017). Economic impact of ocean acidication on shellsh production
in Europe. Journal of Environmental Planning and Management 60, 500 – 518.
Pauly, D. & Cheung, W. W. L. (2017). Sound physiological knowledge and principles in odelling
shringking of shes under climate change. Global Change Biology 24, e15–e26.
Pauly, D. & Zeller, D. (2016). Catch reconstructions reveal that global marine sheries catches
are higher than reported and declining. Nature Communications 7, 10244.
Perry, R. I., Cury, P., Brander, K., Jennings, S., Möllmann, C. & Planque, B. (2010). Sensitivity
of marine systems to climate and shing: concepts, issues and management responses.
Journal of Marine Systems 79, 427– 435.
Pitcher, T. J. & Cheung, W. W. L. (2013). Fisheries: hope or despair? Marine Pollution Bulletin
74, 506–516.
Poloczanska, E. S., Brown, C. J., Sydeman, W. J., Kiessling, W., Schoeman, D. S., Moore, P.
J., Brander, K., Bruno, J. F., Buckley, L. B., Burrows, M. T., Duarte, C. M., Halpern, B.
S., Holding, J., Kappel, C. J., O’Connor, M. I., Pandol, J. M., Parmesan, C., Schwing,
F., Thompson, S. A. & Richardson, A. J. (2013). Global imprint of climate change on
marine life. Nature Climate Change 3, 919– 925.
Pörtner, H. O. & Farrell, A. P. (2008). Physiology and climate change. Science 322, 690 – 692.
Pörtner, H.-O., Karl, D. M., Boyd, P. W., Cheung, W., Lluch-Cota, S. E., Nojiri, Y., Schmidt, D.
N. & Zavialov, P. O. (2014). Ocean systems. In Climate Change 2014: Impacts, Adapta-
tion and Vulnerability. Part a: Global and Sectoral Aspects. Contribution of Working
Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803

FISHES AND FISHERIES IN THE CHANGING OCEANS 803
Change (Field, C. B., Barros, V. R., Dokken, D. J., Mach, K. J., Mastrandrea, M. D.,
Bilir, T. E., Chatterjee, M., Ebi, K. L., Estrada, Y. O., Genova, R. C., Girma, B., Kissel,
E. S., Levy, A. N., MacCracken, S., Mastrandrea, P. R. & White, L. L., eds), pp. 411 –484.
Cambridge, MA: Cambridge University Press.
Schmidtko, S., Stramma, L. & Visbeck, M. (2017). Decline in global oceanic oxygen content
during the past ve decades. Nature 542, 335– 339.
Stock, C. A., John, J. G., Rykaczewski, R. R., Asch, R. G., Cheung, W. W. L., Dunne, J. P.,
Friedland, K. D., Lam, V. W. Y., Sarmiento, J. L. & Watson, R. A. (2017). Reconciling
sheries catch and ocean productivity. Proceedings of the National Academy of Sciences
of the U.S.A. 114, E1441– E1449.
Stocker, T. F., Qin, D., Plattner, G. K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y.,
Bex, B. & Midgley, B. M. (Eds) (2013). IPCC, 2013: Climate Change 2013: The Physical
Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the
Intergovernmental Panel on Climate Change. Cambridge, MA: Cambridge University
Press.
Sumaila, U. R., Cheung, W. W. L. & Teh, L. (2007). Rebuilding Hong Kong’s marine sheries:
an evaluation of management options. In Fisheries Centre Research Reports 2017
15.Vancouver: Fisheries Centre, University of British Columbia Available at www
.open.library.ubc.ca/cIRcle/collections/facultyresearchandpublications/52383/items/1
.0074747
Sumaila, U. R., Cheung, W., Dyck, A., Gueye, K., Huang, L., Lam, V., Pauly, D., Srinivasan, T.,
Swartz, W., Watson, R. & Zeller, D. (2012). Benets of rebuilding global marine sheries
outweigh costs. PLoS One 7, e40542.
Watson, R. A., Cheung, W. W. L., Anticamara, J. A., Sumaila, R. U., Zeller, D. & Pauly, D.
(2013). Global marine yield halved as shing intensity redoubles. Fish a nd Fisheri es 14,
493–503.
Weatherdon, L. V., Ota, Y., Jones, M. C., Close, D. A. & Cheung, W. W. L. (2016). Projected
scenarios for coastal rst nations’ sheries catch potential under climate change: man-
agement challenges and opportunities. PLoS One 11, e0145285.
Wittmann, A. C. & Pörtner, H.-O. (2013). Sensitivities of extant animal taxa to ocean acidica-
tion. Nature Climate Change 3, 995– 1001.
Worm, B., Hilborn, R., Baum, J. K., Branch, T. A., Collie, J. S., Costello, C., Fogarty, M. J.,
Fulton, E. A., Hutchings, J. A., Jennings, S., Jensen, O. P., Lotze, H. K., Mace, P. M.,
McClanahan, T. M., Minto, C., Palumbi, S. R., Parma, A. M., Ricard, D., Rosenberg, A.
A., Watson, R. & Zeller, D. (2009). Rebuilding global sheries. Science 325, 578– 585.
© 2018 The Fisheries Society of the British Isles, Journal of Fish Biology 2018, 92, 790–803