My Research Activities
The majority of my research focuses on the physiological responses of marine species to ocean change, mainly ocean acidification, hypoxia, and ocean warming. I am interested in scaling these individual and species level responses to community level responses in order to understand how changes in chemical and physical oceanography will drive changes in community function. This information can then be used to inform conservation and adaptive management strategies for ensuring our continued aim of a sustainable relationship with the ocean in the face of rapid environmental change.
Below are key research themes that I have been/am involved in. Select a topic to find out more!
Below are key research themes that I have been/am involved in. Select a topic to find out more!
The European Lobster in a Changing OceanSymbiotic Salamanders |
Using Natural Volcanic Vents as an Analogue for Future Change |
Ocean Acidification (OA) and ocean warming are one of the most pressing human-related threats to marine systems worldwide. As CO2 is released into the atmosphere, it dissolves into the oceans where it undergoes a sequence of chemical reactions, ultimately resulting in decreased pH and calcite/aragonite saturation states.
Occurring simultaneously to OA is the warming of the worlds oceans. As the atmosphere heats up due to increased emissions, a portion of this heat energy is transferred to the oceans, increasing the average surface temperature.
The combination of changing carbonate chemistry due to OA along with warming of the worlds oceans is not good news for calcifying marine invertebrates, a group which includes many economically important species such as lobster and oysters. A lot of research has taken place assessing the impacts of OA, warming, and combinations of the two on marine species, populations, and ecosystems over the last 10 years or so. Below are a few of the more specific areas relating to climate change research that I am interested in.
Occurring simultaneously to OA is the warming of the worlds oceans. As the atmosphere heats up due to increased emissions, a portion of this heat energy is transferred to the oceans, increasing the average surface temperature.
The combination of changing carbonate chemistry due to OA along with warming of the worlds oceans is not good news for calcifying marine invertebrates, a group which includes many economically important species such as lobster and oysters. A lot of research has taken place assessing the impacts of OA, warming, and combinations of the two on marine species, populations, and ecosystems over the last 10 years or so. Below are a few of the more specific areas relating to climate change research that I am interested in.
European lobster in a changing ocean - Developmental Physiology
My PhD research at Plymouth University, in collaboration with the Plymouth Marine Laboratory and the National Losbter Hatchery, UK, was titled "The effects of elevated temperature and pCO2 on the developmental eco-physiology of the European lobster, Homarus gammarus (L.)".
In general, decapod crustaceans (such as crabs and lobsters) are thought to be relatively tolerant to the effects of OA as they possess good acid-base buffering capabilities (their ability to regulate internal pH in the face of changes to external pH). It is possibly for that reason that decapods, especially both the European H. gammarus and the North American H. americanus, have received a lot less attention than the more sensitive invertebrates such as bivalves and corals. However, as we start to try to understand things such as what makes certain species more tolerant to OA than others, we are starting to get more of an understanding of the complicity in judging tolerance over complicated life cycles and how such tolerance to OA comes at a cost. Such costs, which may often manifest themselves as sub-lethal changes in physiology, growth, or development, are crucial when considering how commercially important species such as lobster will respond to future climate change.
My PhD research on the European lobster focused on how underlying physiological responses to OA, warming, and combinations of the two, during larval and early juvenile development can underlie life history responses such as growth and survival. This may ultimately lead to developmental bottlenecks, as key transitional stages turn out to be more sensitive to OA and warming than other relatively tolerant stages.
More to come...
In general, decapod crustaceans (such as crabs and lobsters) are thought to be relatively tolerant to the effects of OA as they possess good acid-base buffering capabilities (their ability to regulate internal pH in the face of changes to external pH). It is possibly for that reason that decapods, especially both the European H. gammarus and the North American H. americanus, have received a lot less attention than the more sensitive invertebrates such as bivalves and corals. However, as we start to try to understand things such as what makes certain species more tolerant to OA than others, we are starting to get more of an understanding of the complicity in judging tolerance over complicated life cycles and how such tolerance to OA comes at a cost. Such costs, which may often manifest themselves as sub-lethal changes in physiology, growth, or development, are crucial when considering how commercially important species such as lobster will respond to future climate change.
My PhD research on the European lobster focused on how underlying physiological responses to OA, warming, and combinations of the two, during larval and early juvenile development can underlie life history responses such as growth and survival. This may ultimately lead to developmental bottlenecks, as key transitional stages turn out to be more sensitive to OA and warming than other relatively tolerant stages.
More to come...
Energy Budgets and Ocean Acidification
As previously mentioned, tolerance to OA can come with costs that manifest themselves often as sub-lethal but crucial effects. Another area of interest that I have been developing since my undergraduate degree at Plymouth University is that of energy demand and budgeting.
When decapod crustaceans such as the velvet swimming crab, Necora puber, are exposed to increased pCO2 they utilize bicarbonate buffering to regulate internal pH. This process involves the movement of a range of different ions across gill surfaces with the use of transport enzymes and ultimately results in an increase in haemolymph HCO3 in exchange for H+. This process, while allowing decapods to withstand short periods of increased pCO2, is an energy demanding one deu to the amount of enzyme transport involved. However, so far the long term consequences of such energy demand is unknown. In shorter term studies with adult N. puber and juvenile H. gammarus, we have found that energy demand from acid-base balance increases resulting in a miss-match in energy demand and supply resulting in decreased feeding activities and depleted energy stores.
More to come...
When decapod crustaceans such as the velvet swimming crab, Necora puber, are exposed to increased pCO2 they utilize bicarbonate buffering to regulate internal pH. This process involves the movement of a range of different ions across gill surfaces with the use of transport enzymes and ultimately results in an increase in haemolymph HCO3 in exchange for H+. This process, while allowing decapods to withstand short periods of increased pCO2, is an energy demanding one deu to the amount of enzyme transport involved. However, so far the long term consequences of such energy demand is unknown. In shorter term studies with adult N. puber and juvenile H. gammarus, we have found that energy demand from acid-base balance increases resulting in a miss-match in energy demand and supply resulting in decreased feeding activities and depleted energy stores.
More to come...
Natural Analogues for a High CO2 World
More to come...