Farmers are being urged to: maintain native flowering hedgerows; allow wild flowers to grow; provide nesting places for wild bees; minimise fertiliser use; and reduce pesticide inputs.

Appropriately for the day that’s in it – as today (Sunday, May 20) marks World Bee Day – new research from the National Biodiversity Data Centre shows that the Irish bumblebee populations are still in decline.

The All-Ireland Bumblebee Monitoring Scheme, co-ordinated by Dr. Tomas Murray, senior ecologist at the National Biodiversity Data Centre, has revealed marked losses in native bumblebee species.

The bumblebee populations recorded in 2017 were the lowest they have been since monitoring began in 2012.

The current overall trend from 2012-2017 is a year-on-year decline of 3.7%, leading to a total loss of 14.2% from 2012-2017.

Ireland has 21 species of bumblebee. These insects are vital pollinators of crops and wild plants, according to Juanita Browne, All-Ireland pollinator plan project officer.

Without pollinators, the crops farmers can grow will be limited. 100 crops provide 90% of the world’s food – 71 are pollinated by bees.

“Without pollinators, it would also be impossible to grow our own fruits and vegetables at home and wildflowers would disappear, making the countryside a less attractive and colourful place,” she said.

“If our wild pollinators disappear, we can’t bring them back. It will mean less diversity on our dinner plates and less colour in the countryside.”

Findings released recently are based on the past six years of monitoring the country’s eight most common bumblebee species – as sufficient information has already been gathered on these to accurately assess changes.

The current monitoring scheme stretches across over 100 sites across the island of Ireland and as this expands and the monitoring scheme matures, more species will be included in the analyses.

“Based on a 2006 red list of Ireland’s bees, we already knew that six of our rarer 21 bumblebee species are threatened with extinction from this island,” said Dr. Murray.

“These include the charismatic Great Yellow bumblebee now confined to the north-west and the Shrill Carder bee, with its distinctive buzz, now only found in isolated populations in the west. Indeed, of our 98 wild bee species which includes 77 solitary bees, one-third are threatened with extinction,” he said.

For the first time, these new findings from Dr. Murray’s All-Ireland Bumblebee Monitoring Scheme provide an early warning signal on how Ireland’s more common species are faring.

The large carder bee – Bombus muscorum – is threatened across Europe and, despite Ireland having relatively widespread populations of this species, Dr. Murray has observed a 23% decline in the numbers seen since 2012.

Given the variability around our estimate, we have to be cautious about not crying wolf – but it is telling that we are detecting moderate declines in widespread species after only six years.

“When we drill down into the data and isolate the eight species where we have enough information to accurately estimate how their populations have changed, one is increasing, two are decreasing and five are too variable to assign a trend,” said Dr. Murray.

“It is only thanks to the generosity of 80 ‘citizen scientist’ volunteers across over 100 sites who take part in the All-Ireland bumblebee monitoring scheme that we are able to detect these declines,” he said.

Volunteers walk a fixed route 1-2km walk once a month from March to October and count the number and type of each bumblebee they observe using a standardised methodology.

“In 2017, we collectively walked 883.2km over 490 hours, and counted 12,969 bumblebees across 14 species, making this one of the first national ‘citizen science’ schemes in the world that tracks changes in wild pollinator populations.

“Given that we’re seeing six-fold differences in the number of bumblebees across sites means we now have excellent information on what makes a ‘good’ or ‘bad’ bumblebee area,” Dr. Murray said.

Anyone keen to make their farm the best they can for bees should consult the All-Ireland Pollinator Plan, which has 81 actions, on the project website.

Concluding on a positive note, Juanita said:

The All-Ireland pollinator plan is such an exciting project. Yes, bees are declining, but the good news is we know exactly what we need to do to help bees, and the actions needed are very doable and will show results almost immediately.

Dr. Una FitzPatrick, project co-ordinator for the plan, said the results underlined the urgency with which everyone should get behind the plan.