Catchment News

New EPA Research Report 447: Macroalgal Blooms in Transitional and Coastal Waters; Management – Pressures, Policy, and Solutions

The EPA has published EPA Research Report 447: Macroalgal Blooms in Transitional and Coastal Waters; Management – Pressures, Policy, and Solutions. This research, led by the University of Galway, focused on Macroalgal blooms in transitional and coastal waters to develop and test innovative methods, including Earth observation technologies and bio monitors, to monitor and manage algal blooms

Eutrophication of waters and consequent algal blooms place significant pressure on marine ecosystems. Reducing the nutrient load of these waters is essential for ecosystem restoration.

The aim of the MACRO-MAN project was to develop innovative methods for the assessment of the environmental quality of Irish estuaries, and to identify drivers of and management strategies for macroalgal blooms. The potential risks associated with macroalgal blooms were considered in a global change context (e.g. climate change, emerging contaminants, biological invasions) in order to investigate the impact on ecosystem functioning and services provided by Irish estuaries.

Earth observation technologies from the European Space Agency and algorithms developed during the project were used to map the spatial and temporal distribution of brown, green and red macroalgal blooms in Irish estuaries, including the reconstruction of the invasion of a red Asian seaweed (Gracilaria vermiculophylla) in the Clonakilty estuary. Based on the nitrogen isotopic signature of the bloom-forming species, agricultural sources of nitrogen were the biggest drivers of blooms in rural locations, while effluent from wastewater treatment plants was more relevant in urban areas. Tissue nitrogen and phosphorus content indicated that anthropogenic nitrogen enrichment of aquatic environments has produced a shift from a nitrogen to a phosphorus-limited ecosystem.

Image from the report

Learn more:–pressurespolicy-and-solutions-macro-man.php


Ricardo Bermejo, Nessa Golden, Sara Haro, Sita Karki, Michéal MacMonagail, Sara García-Poza, Teresa Navarrete-Fernández, Benedikt Brunner, Kay Knöller, Mark Healy, Owen Fenton, Per-Erik Mellander and Liam Morrison

Who is involved?

Quite simply, everyone in Ireland has a role to play. This can be from something as simple as making sure you don’t pollute your local stream, or a local community working together to establish a Rivers Trust to enhance the rivers and lakes in their area, to a Government Department or Agency helping a Minister implement a new policy to help protect and enhance all our water bodies.

This website has been developed and is maintained by the Environmental Protection Agency, and is a collaboration between the Department of Housing, Planning and Local Government, the Environmental Protection Agency, and the Local Authority Waters Programme.


Local Authority Waters Programme

The Local Authority Waters Programme coordinates the efforts of local authorities and other public bodies in the implementation of the River Basin Management Plan, and supports local community and stakeholder involvement in managing our natural waters, for everyone’s benefit.


Environmental Protection Agency

The EPA is responsible for coordinating the monitoring, assessment and reporting on the status of our 4,842 water bodies, looking at trends and changes, determining which waterbodies are at risk and what could be causing this, and drafting environmental objectives for each.


Department of Housing, Local Government and Heritage

The Department is responsible for making sure that the right policies, regulations and resources are in place to implement the Water Framework Directive, and developing a River Basin Management Plan and Programme of Measures to protect and restore our waters.