Bryony A. Caswell

• Senior Lecturer at University of Hull

Marine functional connectivity (MFC) refers to the flows of organic matter, genes, and energy that are caused by the active and passive movements of marine organisms. Occurring at various temporal and spatial scales, MFC is a dynamic, constantly evolving global ecological process, part of overall ecological connectivity, but with its own distinct a...

Extreme global warming and environmental changes associated with the Toarcian (Lower Jurassic) Oceanic Anoxic Event (T-OAE, ~183 Mya) profoundly impacted marine organisms and terrestrial plants. Despite the exceptionally elevated abundances of fossil insects from strata of this age, only assemblages from Germany and Luxembourg have been studied in...

Benthic foraminiferal turnover during the Palaeocene–Eocene Thermal Maximum (PETM) has been extensively studied but numerous questions remained unresolved, question such as why some foraminiferal species went into extinction at a particular location but survive in another or why some species survive in extremely low oxygen environment. Because fora...

Benthic foraminiferal turnover during the Palaeocene–Eocene Thermal Maximum (PETM) has been extensively studied but numerous questions remained unresolved, question such as why some foraminiferal species went into extinction at a particular location but survive in another or why some species survive in extremely low oxygen environment. Because fora...

Climate change is undermining the health and integrity of seafloor ecosystems, with declines in bioturbation expected to impact future ecosystem functioning. We explored changes in the nature and degree of bioturbation during Early Jurassic global warming and ocean deoxygenation. Understanding how these communities responded can help anticipate how...

Context Understanding how ecosystems function to deliver services is essential if we are to limit the impacts off human activities. Aim We hypothesised that increased densities of whelk, Pyrazus ebeninus, and crab, Macrophthalmus setosus, up to four times (given their large body-size and ecological roles, e.g. consuming deposits and disturbing sed...

Case studies in support of Caswell et al. 2020.

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...

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...

A growing volume of evidence shows that the broad-scale biogeographic redistribution of species is occurring in response to increasing global temperatures. The present study documents poleward movements of up to eight species of nominally ‘tropical’ macroinvertebrates (molluscs, polychaetes, crustaceans and foraminifera) from intertidal mudflats on...

The world’s coastlines have become heavily modified over the last century, with the adjacent natural habitats declining in biodiversity and health under increasing pressure from urbanisation. In this study we assessed the structure and biological traits of macrofaunal assemblages from 24 south-east Queensland mudflats in order to determine whether...

Increasingly environmental management seeks to limit the impacts of human activities on ecosystems relative to some 'reference' condition, which is often the presumed pre-impacted state, however such information is limited. We explore how marine ecosystems in deep time (Late Jurassic) are characterised by AZTI's Marine Biotic Index (AMBI), and how...

Increasingly environmental management seeks to limit the impacts of human activities on ecosystems relative to some ‘reference’ condition, which is often the presumed pre-impacted state, however such information is limited. We explore how marine ecosystems in deep time (Late Jurassic) are characterised by AZTI's Marine Biotic Index (AMBI), and how...

During the Toarcian oceanic anoxic event (OAE) considerable environmental changes occurred that were associated with global warming, perturbations to the C-cycle and ocean deoxygenation which resulted in a mass extinction of marine fauna. Recovery of the biota after the event was protracted and has to date undergone limited study. However, understa...

Climate change and anthropogenic nutrient enrichment are driving rapid increases in ocean deoxygenation. These changes cause biodiversity loss and have severe consequences for marine ecosystem functioning and in turn the delivery of ecosystem services upon which humanity depends (e.g. fisheries). We seek to understand how such changes will impact s...

Mudflats - unvegetated, soft-sediment, intertidal habitats-support macrofaunal assemblages that contribute to a number of important ecosystem functions (e.g. food for fish and birds, nutrient and C-cycling). These habitats are widespread but are threatened by increasing pressure from anthropogenic activities. Greater knowledge of the consequences o...

As a society, we use more than 100,000 different industrial compounds to promote health and treat disease, to grow food and to access clean water. While technological developments have improved our lives, most of these compounds end up in our oceans where they threaten marine life and human health. The practice of ocean waste disposal has had a lon...

Detailed study of benthic foraminifera trait composition from Shatsky Rise and Alamedilla show that trait changes in foraminfera positively correlate in both locations during the early Eocene hyperthermal. We are exploring if this can be replicated in other basins as well as its similarity or differences with the faunal turn over

Global warming during the Early Jurassic, and associated widespread ocean deoxygenation, was comparable in scale with the changes projected for the next century. This study quantifies the impact of severe global environmental change on the biological traits of marine communities that define the ecological roles and functions they deliver. We docume...

The motivation of this project is to study the feedback of extreme climate on ecosystem services provided by the zooplanktons specifically, foraminifera. Changes in traits of microfossils reflect the environment in which they lived and allow us to understand how the ocean environment and ecosystem changed during past climate extremes. We have Measu...

Predicting the ability of the biosphere to continue to deliver ecosystem services in the face of biodiversity loss and environmental change is a major challenge. The results of short-term and small-scale experimental studies are both equivocal and difficult to extrapolate from. In this study we use data on benthic palaeocommunities covering 4,000,0...

We have reinvestigated the marine mass extinction interval that occurred during the early Toarcian, which was a time of widespread marine anoxia. The ranges of marine benthic invertebrates are significantly altered using new observations from the Cleveland Basin, UK. Goniomya rhombifera is reported for the first time from the Whitby Mudstone Format...

Extreme environmental change during the Toarcian Oceanic Anoxic Event had widespread impacts on marine biota. This study provides new evidence, from the Yorkshire coast sections, UK, that the event was associated with periods of elevated fish and ammonite mortality. Using a synthesis of pelagic macrofaunal changes, benthic macrofaunal data and geoc...

It is widely acknowledged that human activities are contributing to substantial biodiversity loss and that this threatens ecological processes underpinning human exploitation of ‘ecosystem services’ (defined by the Millennium Ecosystem Assessment as ‘the benefits people obtain from ecosystems’). In the present study we consider three ‘intermediate...

Deoxygenation has profound effects on marine biota and delivery of ecological functions in benthic systems. Globally, coastal and oceanic hypoxia is rapidly increasing due to anthropogenic activities including climate change and eutrophication. Little is known about the response of marine ecosystems to deoxygenation over long timescales and the con...

Severe paleoclimatic change during the Toarcian (Early Jurassic) oceanic anoxic event (OAE) was characterized by a negative δ13C excursion, increased weathering, higher seawater temperatures, oceanic deoxygenation, and mass extinction. We present abundance and size data (n ≈ 36,000) for the two dominant epifaunal bivalve species from the Toarcian O...

The global deposition of organic rich-mudrocks, a mass extinction, and marked geochemical changes in the sedimentary rocks and fossils deposited during the early Toarcian indicates a period of extreme environmental change and an oceanic anoxic event. This study investigates at a high-resolution the environmental and biotic changes that occurred dur...

We have reinvestigated the marine mass extinction interval that occurred during the early Toarcian, which was a time of widespread marine anoxia. The ranges of marine benthic invertebrates are significantly altered using new observations from the Cleveland Basin, UK. Goniomya rhombifera is reported for the first time from the Whitby Mudstone Format...

The early Toarcian Oceanic Anoxic Event (OAE; 183 Ma) was associated with a species level extinction of marine fauna and a crisis in the marine phytoplankton. The event lasted c. 250 ka and was characterised by a large, negative C-isotope excursion (CIE) of ~-7 per mil in marine organic matter, marine carbonates and fossilized wood. Geochemical evi...