Non-invasive heart rate measurements in crabs during warming
1 Formål
This application covers an experiment investigating a potential link between heart performance and upper thermal limits in four cold-water crustacean species. Prior to experimentation, crustaceans will be held in housing thanks with aeriated flow-through seawater at optimal temperature. During experimentation, animals will be exposed to an acute thermal challenge whilst heart rate is monitored non-invasively. The acute thermal challenges will be performed in water with different oxygen levels. After experimentation, crustaceans will immediately be returned to the housing tanks. Each animal will be assessed once. The thermal challenge procedure may be stressful for the crustacean, but they recover quickly once they are returned to the housing tanks.
Purpose and aim
A leading IPCC model for forecasting the impacts of marine heatwaves and ocean deoxygenation on aquatic ectotherms proposes a temperature-induced collapse of the cardiac system and insufficient tissue oxygen supply as the principal mechanism underlying their upper thermal limits.
The aim of this study is to test the hypothesis that the upper thermal limits of cold-water species is caused by a temperature-induced collapse of the cardiac system. This will be done via non-invasive measurements of cardiac performance (i.e., heart rate) in cold-water crustaceans exposed to acute thermal challenges.
2 Skadevirkninger
The crustaceans will be subjected to high temperatures that may lead to reduced motor function and reduced heart performance. It can be hypothesised that this is stressful for the crustaceans in the short term (minutes, hours), but long term it doesn't appear to affect the crustaceans as they resume normal behaviour and feeding within hours of being returned to the housing tanks.
3 Forventet nytteverdi
The aim of this study is to test the hypothesis that the upper thermal limits of cold-water species is caused by a temperature-induced collapse of the cardiac system. This knowledge will be used to forecast impacts of climate change on Norwegian decapods, with the aim of protecting crabs from the future impacts of climate change.
4 Antall dyr og art
The main reason for using decapods is that we can measure their heart rate non-invasively. The four study species are chosen because they are cold-water species occupying different thermal habitats, allowing us to investigate potential links between cardiac thermal tolerance and thermal habitats across species. The four study species are also chosen because they live in the waters around Trondheim.
100x Brown crab (Cancer pagurus).
100x European green crab (Carcinus maenas).
100x Norway lobster (Nephrops norvegicus).
100x Great spider crab (Hyas araneus).
5 Hvordan etterleve 3R
We can't replace whole animal experiments because we are investigating the impacts of warming on whole animal function.
We have aimed to reduce the number of animals. For each group, we have used a statistical power analysis to determine the minimum number of animals needed to get conclusive results. This will ensure we are not using more animals than necessary.
We have refined our measurement and handling techniques in previous projects on crabs, so we know how to minimise the impacts on crab welfare.
This application covers an experiment investigating a potential link between heart performance and upper thermal limits in four cold-water crustacean species. Prior to experimentation, crustaceans will be held in housing thanks with aeriated flow-through seawater at optimal temperature. During experimentation, animals will be exposed to an acute thermal challenge whilst heart rate is monitored non-invasively. The acute thermal challenges will be performed in water with different oxygen levels. After experimentation, crustaceans will immediately be returned to the housing tanks. Each animal will be assessed once. The thermal challenge procedure may be stressful for the crustacean, but they recover quickly once they are returned to the housing tanks.
Purpose and aim
A leading IPCC model for forecasting the impacts of marine heatwaves and ocean deoxygenation on aquatic ectotherms proposes a temperature-induced collapse of the cardiac system and insufficient tissue oxygen supply as the principal mechanism underlying their upper thermal limits.
The aim of this study is to test the hypothesis that the upper thermal limits of cold-water species is caused by a temperature-induced collapse of the cardiac system. This will be done via non-invasive measurements of cardiac performance (i.e., heart rate) in cold-water crustaceans exposed to acute thermal challenges.
2 Skadevirkninger
The crustaceans will be subjected to high temperatures that may lead to reduced motor function and reduced heart performance. It can be hypothesised that this is stressful for the crustaceans in the short term (minutes, hours), but long term it doesn't appear to affect the crustaceans as they resume normal behaviour and feeding within hours of being returned to the housing tanks.
3 Forventet nytteverdi
The aim of this study is to test the hypothesis that the upper thermal limits of cold-water species is caused by a temperature-induced collapse of the cardiac system. This knowledge will be used to forecast impacts of climate change on Norwegian decapods, with the aim of protecting crabs from the future impacts of climate change.
4 Antall dyr og art
The main reason for using decapods is that we can measure their heart rate non-invasively. The four study species are chosen because they are cold-water species occupying different thermal habitats, allowing us to investigate potential links between cardiac thermal tolerance and thermal habitats across species. The four study species are also chosen because they live in the waters around Trondheim.
100x Brown crab (Cancer pagurus).
100x European green crab (Carcinus maenas).
100x Norway lobster (Nephrops norvegicus).
100x Great spider crab (Hyas araneus).
5 Hvordan etterleve 3R
We can't replace whole animal experiments because we are investigating the impacts of warming on whole animal function.
We have aimed to reduce the number of animals. For each group, we have used a statistical power analysis to determine the minimum number of animals needed to get conclusive results. This will ensure we are not using more animals than necessary.
We have refined our measurement and handling techniques in previous projects on crabs, so we know how to minimise the impacts on crab welfare.