Bloomin’ Algae is a Citizen Science app for reporting the presence of harmful algal blooms of blue-green algae. The app helps speed up public health warnings and can help teach you how to recognise the risks to you, children and animals.
What are blue-green algae?
Blue-green algae naturally occur in lakes, ponds, canals, rivers and reservoirs around the world. They are actually a type of bacteria, known as cyanobacteria, which can produce toxic chemicals that are very harmful to the health of people and animals. They are particularly a health risk during warm summer months when their concentrations increase in the water to form blooms and scums on the surface. This can look like green or turquoise wispy paint, green scum or clumps of green particles, see the gallery below for examples. Often these surface scums accumulate along the shore where children or dogs play, or where livestock come to drink.
What are the dangers of blue-green algae to pets, people and ecosystems?
Blue-green algae can produce potent toxins that can result in a range of health effects in people and animals. Effects on people coming into contact with toxic scums include skin rashes, eye irritations, vomiting and diarrhoea, fever and pains in muscles and joints. Blue-green algae have caused the deaths of dogs, horses, cattle, birds and fish across the UK. If you are a pet owner you can find further information from the Blue Cross.
If you, or your pet, have become unwell after contact with water that you think may be contaminated with blue-green algae, we’d strongly recommend that you seek immediate medical or veterinary advice.
Download our information poster on blue-green algae for landowners, land managers or local authorities to use. This poster gives advice on what blue-green algae look like, health risks, how to stay safe and where to go for more help and advice.
- A print-ready PDF
- A web-ready PDF
- An editable version (PPT) for you to add your local contact details
The app and how to help
“Bloomin’ Algae” is developed by the Centre for Ecology & Hydrology for the general public to record the presence of possible harmful algal blooms in freshwaters around the UK. You can download the app directly from Google Play or App Store or use the QR code to find a link to the download sites.
By sending in your records of blue-green algae, through this app, you can help provide a rapid and more comprehensive picture of harmful algal blooms across the UK. This will help inform local authorities and relevant health agencies of potential public health risks in your area so that they can provide early warning to the public. As well as recording the location and date of the bloom, we need you to submit a photo of the bloom to help us verify your record. Optionally, we ask you to tell us what activities take place at the lake e.g. swimming, dog walking, etc. This is to gauge the potential health risks to people or animals. If you register for an account, we can provide you with feedback on your record that can help you learn how to identify blue-green algae with more confidence.
You can view submitted records for the UK on the iRecord website or on the map on this page.
Using the app
1. Identifying blue-green algae
You can use the “Algal guide” in the app and the gallery below. Blue-green algae can form dense surface scums or green wisps on the surface. Duckweed and filamentous algae can be mistaken as blue-green algae but are harmless. One method you can use to check if it is blue-green algae is to poke the algae with a stick and if it breaks into small particles, or irregular-shaped clumps, it is likely to be blue-green algae. If, however, it has tiny round leaves (about 2-4 mm) it is most likely duckweed. If the stick brings up clumps of hair-like strands or soft tubes then it is harmless filamentous algae.
WARNING: Do NOT touch anything you suspect to be a bloom and do NOT allow pets or children to come into contact with, or swallow, the water.
2. Register and activate your user profile
When you submit your first record you will be asked to register an account with iRecord (the Citizen Science software we use). You can register for an account by clicking the menu button in the top left corner; the Register link is at the bottom of the list. After registering with the app you will receive a verification e-mail. We need you to authorise your e-mail address to be able to give you feedback on your submitted records.
3. Making your first record
To make a recording simply fill in the information on the front page of the app. As well as recording the location and date of the bloom, it is important that you submit a photo for us to check whether it is harmful blue-green algae. We also ask you to say what activities take place at the lake e.g. fishing, dog walking, etc. This is to gauge the potential health risks to people or animals.
Recording a precise location: On the “Location” tab you can use your phone’s in-built GPS to record your precise location. We recommend you press the “Locate” button and “Refresh GPS” to improve accuracy. Aim for an accuracy of 20 meters or less. In the “Nearest Named Place” box, you can also type in a place name e.g. “south shore of lake“
Adding photos: To confirm your record it is important you send a clear photo. The “camera icon” at the bottom left of the app front page allows you to submit one or more photos. If you can, we recommend you send a close-up photo of the bloom.
4. Getting notifications of blooms in your area
If you have registered an account with iRecord you can set up an alert to receive email notifications of bloom records in your area. You can do this by going to iRecord's Species alert notifications and asking for notifications of “Cyanobacteria” species. Three options are proposed when typing “Cyanobacteria” – you should pick the top option listed. You can then select your location: either a whole country or the county you wish to receive notifications from. You will now receive an email about any submitted record in your area. If you want to receive records from more than one county, you need to repeat this notification process for each area of interest as only one area can be selected each time.
Partners involved in the app
The design of the app has been reviewed by representatives from the UK environment agencies (Environment Agency, Scottish Environment Protection Agency) and by Public Health England & Health Protection Scotland.
Further action and reporting harmful algal blooms
The responsibility to manage algal blooms lies with the owner of the water concerned. However, for enquiries relating to blue-green algae (cyanobacteria), please contact the environmental health department in your local authority. Environmental health will assess any action required against the relevant guidance and may contact the regulatory authority (EA, SEPA, NRW, EANI) for further water tests. You may also directly report incidents of algal blooms or water pollution incidents to your environment regulatory authority.