Preventing Fish Deaths: Regular Oxygen Infusion in English Rivers
Introduction:
English rivers have been given emergency oxygen on almost 100 occasions in the past five years to save fish from dying. This is due to factors such as sewage dumping and hot weather reducing oxygen levels in the water. The Environment Agency uses measures such as pumping liquid hydrogen peroxide and mechanical aerators to increase oxygen levels. Climate change is expected to increase the need for emergency oxygen in the future. This highlights the ongoing challenges faced by fish populations and the importance of protecting rivers against the impacts of climate change.
Full Article: Preventing Fish Deaths: Regular Oxygen Infusion in English Rivers
Emergency Oxygenation Saves Fish in English Rivers from Dying
Emergency oxygenation at a fishery in Worcestershire, UK, last year
The Environment Agency
In a desperate attempt to save fish from dying, English rivers have undergone emergency oxygenation on nearly 100 occasions in the last five years, according to a report by New Scientist.
Rivers in Trouble
Rivers can become depleted of oxygen due to various factors, including sewage dumping that promotes the growth of bacteria and algae. These organisms consume oxygen, leading to a decrease in oxygen levels. Additionally, hot weather exacerbates the problem as warmer water holds less oxygen.
Emergency Measures in Place
To combat these issues, the Environment Agency (EA) in England has implemented emergency measures to pump oxygen into rivers, preventing fish and plant deaths.
According to a freedom of information request, the EA performed emergency oxygenation on 25 occasions last year alone. Between 2018 and 2021, there were a total of 74 deployments. These figures only represent 13 out of 14 operating areas, and data for 2023 is not available yet. Therefore, the actual number of emergency oxygen deployments in the past five years is likely higher than 99.
Graeme Storey, fisheries manager at the EA, believes anecdotally that the use of emergency oxygen measures has increased in recent years. He advises looking out for signs of distressed fish, such as gasping for air, appearing lethargic, and dead fish floating on the surface.
Methods Used
The EA utilizes various methods to pump oxygen into rivers, including the use of liquid hydrogen peroxide, which breaks down into water and oxygen. Mechanical aerators are also employed to increase oxygen levels by disturbing the water’s surface. Storey notes that mechanical aeration is slower but effective for chronic issues like algal blooms.
The Impact of Climate Change
Storey warns that climate change is likely to exacerbate the need for emergency oxygenation in rivers. Rising temperatures and extreme rainfall events, in combination with existing pressures on the aquatic environment, present ongoing challenges for fish populations and fisheries.