Established in 2007 by the National Biodiversity Data Centre, the Irish Butterfly Monitoring Scheme supports and co-ordinates a network of volunteer recorders across Ireland.  The scheme has monitored butterflies on a weekly basis at almost 90 sites nationally, and these walks generate extremely valuable data to enable us to track butterfly populations from year to year and gain insights into the impact of climate change on butterflies.

Why do we need a butterfly monitoring scheme?

In 2010, the Irish Butterfly Red List found that, of the 35 resident and regular migrant species of Irish butterfly, one species is now extinct, six species are threatened with extinction and five species are of ‘Near Threatened’ status. Therefore, 18% of our butterfly species are now under threat, with another 15% heading in the same direction.

In terms of population size, data gathered for the European Grassland Butterfly Indicator from 4,500 Butterfly Monitoring Scheme sites across 22 European countries, including Ireland, show that since 1990 we have lost 30% of our grassland butterfly populations.

Butterflies are extremely important indicators of the state of Ireland’s environment and action is urgently needed to halt their decline and restore an Irish countryside rich in butterflies. Our ongoing monitoring scheme allows us to objectively prioritise conservation action for already endangered species and cost-effectively prevent other species from being driven toward extinction.

The Butterfly Monitoring Scheme is also an ideal tool for individuals, community groups and professional land managers to measure change in their local biodiversity. The ongoing recording of butterfly communities provides a sensitive metric against which changes in land-use and its impact on our biodiversity can be monitored.


Frequently asked questions:


Do I need to input the route of my walk online or fill in a transect details form every week?

No, you only need to register your walk with us online here or fill in the Transect Details Form once when you first join the Butterfly Monitoring Scheme.


How can I find a grid reference?

There are two ways of doing this. You can obtain the grid reference for the starting point of your transect by finding its location on an ordnance survey map. Or, if you go to the website, you can zoom in to your area and click the mouse button which will bring up the grid reference at the top of the screen. Alternatively, if you give us the name of the townland where your transect is located, we can get it for you.


Does the transect have to be located in any designated area?

No, your transect should be somewhere you enjoy walking and is convenient for you. However, do try to avoid built-up areas and main roads.


If a transect is a straight route, does one record butterflies both ways?

No, butterflies are recorded along one way only. You can decide whether you record them on the way out, or on the way back.


When filling in my Butterfly Site Details online or in the downloadable Transect details form, how do I decide how many sections are in my walk?

We recommend that you break your walk up into 5 to 15 sections, with each section representing an area of relatively uniform habitat.  For example, the 1st section of your walk might be along a hedgerow, the 2nd section would be through a field, the 3rd section through a stand of braodleaf trees etc.  You may also break up long parts of your walk into sections based on some landmark, for example, you have 1 km of a path beside a hedgerow: the 1st 300 m until a tall tree is section 1, the next 400 m  ends by a junction in the path and the next 300 m ends where the path joins a road.  How you break up your walk is it up to you, but for each section you need to outline what the main habitat type is and what management may or may not be present.


When filling in my Butterfly Site Details online or in the downloadable Transect details form, what is meant by ‘habitat’?

Habitat is the area that is inhabited by a species. For each section of your walk, specify whether the habitat is grassland, bog, woodland, garden, river, marsh etc.  A detailed breakdown of the habitat classification used in Butterfly Monitoring Scheme can be found [here].


When filling in my Butterfly Site Details online or in the downloadable Transect details form, what is meant by ‘management’?

By ‘management’, we want to know if there is any mowing, grazing, hedge-cutting, application of pesticides, no management etc. for each section of your walk.


How do I get my records to you?

By registering your walk with us online here and inputting your records under the ‘Butterfly Monitoring’ -> ‘My Butterfly Walks’ section of your online account.  The full details of how to do this can be found here.


The white butterflies are difficult to identify – how do I record them?

They are indeed difficult to identify, but there is an estimation one can apply. For example: if you see about 20 white butterflies, but only manage to identify 10, of which 8 might be green-veined whites and 2 are small whites, then you can extrapolate that to 16 Green-veined Whites and 4 Small Whites.