Butterfly and bee species are disappearing from the Irish landscape

Click HERE to listen to report for Drivetime on RTE Radio 1

(Broadcast 5th June, 2017)

Peacock_on_Common_Knapweed800
The numbers and diversity of Ireland’s butterflies and bees is in steep decline. Pictured here is a Peacock butterfly on Common Knapweed (Credit: Jesmond Harding, Butterfly Conservation Ireland) Butterfly Conservation Ireland,

Butterflies, and bees provide a number of ecological services essential for any landscape – including pollination and   – and their numbers and diversity in an area are considered to be excellent indicators of how well insects generally are doing in a landscape.

To see how they are getting on in the Irish landscape I visited Ballyannan woods near Midleton in Cork. This is an area where cultivated fields with neat rows of potato plants lie next to Ballyannan woods, a mixed woodland, containing sycamore, beech and natural oak trees popular with local walkers.

The diversity of the landscape here makes it an ideal location for the National Biodiversity Data Centre to carry out weekly butterfly monitoring, along the same designated route, for seven months per year.

I met Dr Tomas Murray an ecologist with the Data Centre and members of a diverse butterfly monitoring and counting group, which included students, older people and people working with local community groups.

It was an  overcast day, and on days like these, it can be more difficult to catch butterflies, but after a little while we were in luck.

Chemicals 

I also spoke to Dr Dara Stanley, a lecturer in Plant Ecology in the Botany and Plant Science Dept at NUI Galway has investigated how human activities are impact on bees in particular, but also butterflies and other insects.

One of Dr Stanley’s research projects focused on the impact of neonicotinoid pesticides, which are used as seed treatments on crops.

Dr Stanley explained to me that the use of chemicals, herbicides and pesticides of all types is killing bees, but also affecting their behaviour and reducing the food that is available to them.

Over the years, many rare species of bumblebee have been migrating westward across Ireland to those areas where hay making, and hay meadows, which are full of flowers, is still common practice.

Changes in agricultural practice too have reduced the places where pollinating insects can live, and reduced the amount of flowers they can eat. The cutting of gardens in suburban landscapes has a similar effect, Dr Stanley said.

Certainly, changes in the landscape over the last half century of so around Midleton and many other parts of Ireland have been dramatic. Much of the change has come about as a result of more intensive use of the land.

Decline

The decline of butterflies and bees in Ireland has been  dramatic, and the question is what can be done to stop or reverse the decline.

An All Ireland Pollinator Plan, a north-south initiative which began in 2015, set out some specific ways that farmers, gardeners and others can help halt or reverse the decline of our pollinators, butterflies and other insects.

The recommendations for farmers include allowing field margins to grow unmanaged encouraging wild grasses to grow, or to introduce wild flower strips.

For gardeners the message is don’t cut the grass too regularly, every six weeks is enough, and allow one small sunny spot to grow unimpeded.

For now, the decline in our biodiversity is reversible, scientists believe, but if ignore the red flags that nature is raising, we’re likely to pay a heavy price for our inaction.