Blue-Green Algae
Lough Neagh, the largest freshwater lake in the UK and Ireland, and forms part of a wider aquatic ecosystem, from its surrounding catchment area to the rivers which flow into it and flow out to the north coast.
In recent years, Lough Neagh has faced increasing pressures and, in 2023, an unprecedented blue-green algal bloom appeared, attracting substantial public interest.
The Cyanobacteria found on Lough Neagh is a natural component of plankton and plays an important ecological role. It produces oxygen and supports the food chain. It would typically have favoured lower light conditions and lived under the surface of the water. However, a combination of factors, including climate change, nutrient run-off from agriculture and wastewater, and invasive species like zebra mussels are considered to have influenced conditions within the Lough.
As conditions have changed, newer species like Microcystis and Anabaena have become more prevalent, forming surface scums during warm, calm spells.
In 2023, the unprecedented bloom was associated with warming waters, still weather, and decades of nutrient build-up in lakebed sediments. These blooms can affect aquatic life and may produce toxins that can pose risks to people, pets, livestock and wildlife.
Scientists from Queen’s University and AFBI have been studying Lough Neagh since the 1960s and since the recent algal bloom, research activity has increased.
Current research by PhD students includes satellite tracking of bloom history, molecular genetics, ecological modelling, and the exploration of nature-based solutions like reforestation, wetland restoration, and riparian buffers, to help reduce nutrient run-off.
Lough Neagh is an important natural asset, and continued research, monitoring and collaborative action will contribute to a better understanding of the challenges it faces and the measures that can support its recovery.
The views and opinions on the subject of this video content are those of the contributors.
Blue-Green Algae – what is it?
Blue-green algal blooms have been visible on Lough Neagh in recent years. In this short film, Adam Mellor of AFBI explains what Blue-Green Algae is.
Blue-Green Algae – what caused it?
Blue-Green Algae has been visible on Lough Neagh in recent years. In this short film, Adam Mellor of AFBI outlines some of the factors contributing to the Blue-Green Algal blooms of 2023.
Nutrient enrichment
In this short film, Adam Mellor of AFBI explains nutrient enrichment and its role in the development of Blue-Green Algal blooms, which are not unique to Lough Neagh.
Emerging contaminants
In this short film, Adam Mellor of AFBI explains that emerging contaminants are being studied to better understand any potential impacts on Lough Neagh and discusses the aim of supporting a healthy and resilient ecosytem.
QUB research
In this short film, Dr Neil Reid of Queen’s University Belfast explains the research that is being undertaken at QUB into early and recent algal blooms. From ecological networks within the Lough to molecular genetics and considering potential remediation and solutions.
What’s the issue?
In this short film, Dr Neil Reid of Queen’s University Belfast explains analysis of toxins produced by Blue-Green Algae taken from the shoreline of Lough Neagh and the potential risks that may arise when blooms occur in high concentrations.
The causes of Blue-Green Algae
In this short film, Dr Neil Reid of Queen’s University Belfast explains that changing conditions have contributed to the Blue-Green Algae on Lough Neagh. The interaction of nutrient enrichment, run off from agriculture and wastewater treatment works, climate change – the water is warmer than it was two decades ago – and invasive species like Zebra mussels.
Nature based solutions
In this short film, Dr Neil Reid of Queen’s University Belfast explains the potential value of low-cost nature-based solutions for the long term.