Georg H Engelhard

Georg H Engelhard
Centre for Environment, Fisheries and Aquaculture Science | CEFAS · Division of Fisheries

PhD, MSc

About

106
Publications
33,692
Reads
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4,067
Citations
Additional affiliations
September 1995 - March 2001
University of Groningen
Position
  • PhD Student

Publications

Publications (106)
Article
The global issues of climate change and marine litter are interlinked and understanding these connections are key to managing their combined risks to marine biodiversity and ultimately society. For example, fossil fuel-based plastics cause direct emissions of greenhouse gases and therefore are an important contributing factor to climate change, whi...
Article
Full-text available
Aquaculture is expanding globally and is an increasingly important component of world food security. However, climate change can impact aquaculture through a variety of mechanisms varying by location and aquaculture type with implications for future productivity. Understanding the risks that climate change poses on different culture systems in diff...
Article
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Fish in coastal ecosystems can be exposed to acute variations in CO2 of between 0.2-1 kPa CO2 (2,000 - 10,000 µatm). Coping with this environmental challenge will depend on the ability to rapidly compensate the internal acid-base disturbance caused by sudden exposure to high environmental CO2 (blood and tissue acidosis); however, studies about the...
Article
Full-text available
Significance We present climate risk analyses for 1) 105 ocean-dependent communities and 2) 380 fishing fleets in Europe. Our unique approach provides a perspective over the climate risks in this diverse and populous continent that is unprecedented in both its breadth and detail. We show that countries in southeast Europe as well as the United King...
Article
As climate change accelerates, species are shifting poleward and subtropical and tropical species are colonizing temperate environments. A popular approach for characterizing such responses is the community temperature index (CTI), which tracks the mean thermal affinity of a community. Studies in marine, freshwater, and terrestrial ecosystems have...
Article
The presence of invasive species in the Mediterranean Sea is much higher than in other European seas, and understanding the reasons behind the range expansion of this invasive species is important for minimising any possible impacts to the already highly pressurised Mediterranean marine ecosystem. In this work, a brief description of sightings of t...
Book
Full-text available
Summary: https://marine.copernicus.eu/news/ocean-state-report-5-summary-now-available Full report: https://www.tandfonline.com/doi/full/10.1080/1755876X.2021.1946240
Preprint
Full-text available
Fish in coastal ecosystems can be exposed to acute variations in CO 2 that can approach 1 kPa CO 2 (10,000 μatm). Coping with this environmental challenge will depend on the ability to rapidly compensate the internal acid-base disturbance caused by sudden exposure to high environmental CO 2 (blood and tissue acidosis); however, studies about the sp...
Preprint
Full-text available
Climate change causes warming, decreased O 2 , and increased CO 2 in marine systems and responses of organisms will depend on interactive effects between these factors. We provide the first experimental assessment of the interactive effects of warming (14 to 22°C), reduced O 2 (~3 – 21 kPa O 2 ), and increased CO 2 (~400 or ~1000 μatm ambient CO 2...
Article
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Sidney J. Holt (1926–2019) was more than a founding father of quantitative fisheries science, and the man who "helped save the great whales." His accomplishments, over a career spanning seven decades, run deeper: he was a champion of reductionism (i.e. able to identify the factors essential for management) and a systemic thinker who inspired scient...
Article
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Seagrasses are globally important, but their extent is decreasing due to the impact of human activities and changing climatic conditions. Seagrass meadows provide vital services, but their condition and distribution are not yet well known, particularly in many small tropical Pacific islands. In 2018, observations and samples were collected from int...
Article
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It has proven extremely challenging for researchers to predict with confidence how human societies might develop in the future, yet managers and industries need to make projections in order to test adaptation and mitigation strategies designed to build resilience to long-term shocks. This paper introduces exploratory scenarios with a particular foc...
Article
Until the late 19th century, extensive beds of flat oyster Ostrea edulis populated the Central North Sea, which have vanished after intensive fisheries. At present, various initiatives are being carried out to investigate the potential to restore this former key species in the area. This historical ecological study contributes by delineating the fo...
Preprint
Full-text available
With the majority of the global human population living in coastal regions, correctly characterising the climate risk that ocean-dependent communities and businesses are exposed to is key to prioritising the finite resources available to support adaptation. We apply a climate risk analysis across the European fisheries sector for the first time to...
Article
Full-text available
The concept of ‘blue growth’, which aims to promote the growth of ocean economies whilst holistically managing marine socio-ecological systems, is emerging within national and international marine policy. The concept is often promoted as being novel, however, we show that, historical analogies exist which can provide insights for contemporary plann...
Article
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1. Ecologists and managers need to understand what types of communities emerge with continued human alterations to ecosystems against a background of natural change. Both natural and anthropogenic drivers are well known to affect organisms’ distributions; however it often remains unclear where along a range of environmental and anthropogenic gradie...
Article
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Fishing – especially trawling – is one of the most ubiquitous anthropogenic pressures on marine ecosystems worldwide, yet very few long-term, spatially explicit datasets on trawling effort exist; this greatly hampers our understanding of the medium- to long-term impact of trawling. This important gap is addressed here for the North Sea, a highly pr...
Article
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Global environmental change is increasing hypoxia in aquatic ecosystems. During hypoxic events, bacterial respiration causes an increase in carbon dioxide (CO2) while oxygen (O2) declines. This is rarely accounted for when assessing hypoxia tolerances of aquatic organisms. We investigated the impact of environmentally realistic increases in CO2 on...
Article
Describing the spatial and temporal dynamics of communities is essential for understanding the impacts of global environmental change on biodiversity and ecosystem functioning. Trait‐based approaches can provide better insight than species‐based (i.e., taxonomic) approaches into community assembly and ecosystem functioning, but comparing species an...
Article
The Commonwealth of Dominica is a Small Island Developing State in the eastern Caribbean, that has been subject to a wide variety of natural hazards over the past century, most recently the Category 5—Hurricane Maria on 18–19 September 2017. In Dominica fishing remains important for income generation and for local food security. While there are sma...
Article
Full-text available
Long-term change in marine environments is frequently investigated by comparison of historical and contemporary trawl catches. Such investigations are challenged by unquantified biases due to advances in gear technology and a lack of knowledge on the fishing power of historical trawl designs. To address this problem, historical surveys can be repea...
Article
Sustainably managing natural resources under climate change requires understanding how species distribution shifts can impact ecosystem structure and functioning. While numerous studies have documented changes in species’ distributions and abundances in response to warming [1, 2], the consequences for the functional structure of ecosystems (i.e., c...
Chapter
Fisheries and aquaculture contribute substantially to the coastal economies of the United Kingdom (UK) and Ireland, and climate change is likely to have significant impacts. Documented effects on fisheries include both losses where availability of traditional stocks are reduced, and new opportunities where abundances increase or new, incoming speci...
Article
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Phytoplankton primary production is at the base of the marine food web; changes in primary production have direct or indirect effects on higher trophic levels, from zooplankton organisms to marine mammals and seabirds. Here we present a new time-series on gross primary production in the North Sea, from 1988 to 2013, estimated using in situ measurem...
Chapter
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Fishers and scientists have known for over 100 years that the status of fish stocks can be greatly influenced by prevailing climatic conditions. Based on historical sea surface temperature data, the North Sea has been identified as one of 20 ‘hot spots’ of climate change globally and projections for the next 100 years suggest that the region will c...
Article
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Studies focussing on long-term changes in squid populations are rare due to limited availability of fisheries-independent data. However, squid play an important role as predator and prey in marine food-webs and have also become an increasingly important target for fisheries. Their short life history is thought to make them particularly sensitive to...
Chapter
Fishing power, which expresses the efficiency by which vessels have the potential to catch fish, has changed dramatically over the past decades to centuries. In historical ecology, two important reasons for studying fishing power change include: (1) understanding change in the capacity (or overcapacity) of fishing fleets and their potential to expl...
Article
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How have North Sea skate and shark assemblages changed since the early 20th century when bottom trawling became widespread, while their environment became increasingly impacted by fishing, climate change, habitat degradation and other anthropogenic pressures? This paper examines long-term changes in the distribution and occurrence of the elasmobran...
Article
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As a discipline, marine historical ecology (MHE) has contributed significantly to our understanding of the past state of the marine environment when levels of human impact were often very different from those today. What is less widely known is that insights from MHE have made headway into being applied within the context of present-day and long-te...
Technical Report
Full-text available
The ICES Working Group on the History of Fish and Fisheries (WGHIST, 2015 -2017) is a forum for interdisciplinary research on social-ecological change in marine and fisheries systems over multi-decadal to multi-century timescales. It comprises a diverse group of researchers including marine biologists, fisheries scientists, historians, and historic...
Article
This study addresses a common assumption in fisheries science: that partial fishing mortality is directly proportional to fishing effort. It is important to challenge this a priori sensible assumption, as it is also built into many models and tools used by the International Council for the Exploration of the Sea (ICES) to help provide advice and co...
Article
Full-text available
Gadus morhua (Atlantic cod) stocks in the Barents Sea are currently at levels not seen since the 1950s. Causes for the population increase last century, and understanding of whether such large numbers will be maintained in the future, are unclear. To explore this, we digitised and interrogated historical cod catch and diet datasets from the Barents...
Article
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The large fish indicator (LFI), or 'proportion of fish greater than 40 cm length in bottom trawl surveys,' is a frequently debated indicator of Good Environmental Status in European regional seas. How does the LFI respond to changes in fishing pressure? This question is addressed here through analysis of fine-scale spatial trends in the LFI within...
Article
1. Well-designed marine protected area (MPA) networks can deliver a range of ecological, economic and social benefits, and so a great deal of research has focused on developing spatial conservation prioritization tools to help identify important areas. 2. However, whilst these software tools are designed to identify MPA networks that both represent...
Conference Paper
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A common presumption in fisheries science is that adult iteroparous fish, once matured, typically spawn in all consecutive years. Recent evidence suggests, however, that skipping of reproduction occurs more commonly than is usually believed. Adult Norwegian spring- spawning herring (Clupea harengus) undertake long annual migrations between feeding,...
Article
Full-text available
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/364393/TTT_FINAL_11Jun14.pdf
Data
Decadal changes in North Sea cod winter distribution, 1970s–2000s, based on fisheries-independent survey cpue (winter IBTS). For each decade, spatial distribution of cod cpue within the grey-shaded region is indicated by the area sizes of the black circles (proportional to cpue). In rectangles where no cpue data were available in a given decade, wh...
Article
Full-text available
Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries-induce...
Article
Full-text available
Globally, spatial distributions of fish stocks are shifting; but although the role of climate change in range shifts is increasingly appreciated, little remains known of the likely additional impact that high levels of fishing pressure might have on distribution. For North Sea cod we show for the first time and in great spatial detail how the stock...
Article
Latitudinal variation in life-history traits is often explained by phenotypically plastic responses or local adap-tations to different thermal regimes. We compared growth, maturation schedules and reproductive invest-ment of female sole Solea solea between 8 populations, covering much of the species' distribution in northern Europe, with respect to...
Article
Biological reference points are important tools for fisheries management. Reference points are not static, butmay change when a population’s environment or the population itself changes. Fisheries-induced evolution is one mechanism that can alter population characteristics, leading to “shifting” reference points by modifying the underlying biologic...
Article
Full-text available
Engelhard, G. H., Peck, M. A., Rindorf, A., Smout, S. C., van Deurs, M., Raab, K., Andersen, K. H., Garthe, S., Lauerburg, R. A. M., Scott, F., Brunel, T., Aarts, G., van Kooten, T., and Dickey-Collas, M. Forage fish, their fisheries, and their predators: who drives whom? – ICES Journal of Marine Science, 71: . The North Sea has a diverse forage fi...
Article
Full-text available
Dickey-Collas, M., Engelhard, G. H., Rindorf, A., Raab, K., Smout, S., Aarts, G., van Deurs, M., Brunel, T., Hoff, A., Lauerburg R. A. M., Garthe, S., Haste Andersen, K., Scott, F., van Kooten, T., Beare, D., and Peck, M. A. Ecosystem-based management objectives for the North Sea: riding the forage fish rollercoaster. – ICES Journal of Marine Scien...
Article
Full-text available
To anticipate the response of fish populations to climate change, we developed a framework that inte-grates requirements in all life stages to assess impacts across the entire life cycle. The framework was applied on plaice (Pleuronectes platessa) and Atlantic herring (Clupea harengus) in the North Sea, Atlantic cod (Gadus morhua) in the Norwegian/...
Article
Phenotypic traits such as peak spawning time may vary within and differ between populations in relation to environmental factors, such as temperature. Sole (Solea solea) is a valuable, commercially exploited species that spawns in late winter or spring. The date of peak spawning was estimated for each year for seven stocks from monthly fish samples...
Article
Full-text available
Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries-induce...
Article
Full-text available
This study compiles 100 years of North Sea demersal landings, focusing on the UK, and relating them to historical events and political, technological and economical drivers that influenced demersal fisheries. In the early twentieth century, aided by technological advances, the UK, and in particular England, had unchallenged dominance in North Sea d...
Article
Full-text available
Plirú, A., van der Kooij, J., Engelhard, G. H., Fox, C. J., Milligan, S. P., and Hunter, E. 2012. Sprat feeding behaviour, selective predation, and impact on plaice egg mortality. – ICES Journal of Marine Science, 69: 1019–1029. Although the causes of fish egg and larval mortality are poorly understood, predation is thought to be a major contributi...