Farmers are being encouraged to grow more native hedgerows, trees and shrubs on their land in a bid to boost the country’s population of pollinators.

The first five-year All Ireland Pollinator Plan 2015-2020 was launched in response to a decline in pollinating insects.

A new version of the plan was subsequently developed and is due to run until 2025.

The initiative, coordinated by the National Biodiversity Data Centre, includes a wide range of stakeholders including local authorities, businesses, Tidy Towns groups, farmers and members of the public.

Marmalade hoverfly on a dandelion. Image: Ruth Wilson
Marmalade hoverfly on a dandelion. Image: Ruth Wilson

According to Ruth Wilson, farmland pollinator officer with the All Ireland Pollinator Plan, wild bees and hoverflies are the most important pollinators.

In Ireland, there are around 100 different species of wild bees, including around 20 bumblebees species and 80 solitary bee species, and 180 species of hoverflies.

Other insects such as moths, butterflies, ants and flies also contribute to pollination.

Wilson said that data collected by volunteers as part of the National Biodiversity Data Centre’s bumblebee monitoring scheme established in 2012 has shown an overall trend of a year-on-year decline of 4%.

The common carder bee, which is among the most common bumblebees, is now showing a moderate decline.

The large carder bee is in severe decline and is limited to small pockets along the west coast.

Wilson said that each insect has a specific role in the natural world and is vital to food production.

“Bumblebee tongues are all different lengths so they specialise in different flowers. Hoverflies prefer flat small-headed plant-like hogweed, so they’re all quite specialised.

“On a global scale, out of 100 crops, 90% of the world’s food is pollinated by wild bees. In the wildlife landscape, around 80% of wild plants depend on pollination,” she told Agriland.

pollinators bees farmers
Buff-tailed Bumble queen feeding on ivy before hibernation. Image: Ruth Wilson

“In the last 50 years, we have been gone down the road of intensive agriculture and that has led to lack of forage and wildflowers in our landscape.

“For the wild bees, they don’t travel far. A bumblebee will just travel 1km from its nest and a solitary bee doesn’t go as far, 300m is the average. So if you consider that they need food nearby,” she said.

“Habitats like our native hedges are just wonderful, they provide a corridor for pollinators to move through a landscape. The bigger and wider that our hedges are is fantastic.

“We need native wildflowers from early spring right through to late-autumn. Some of the early spring ones are willow and blackthorn and it moves through to hawthorn. In the autumn, bramble and ivy are so valuable,” Wilson added.

Some pollinators will just focus on a particular flower while others will be more general in their tastes as the season progresses.

Pollinators on farms

The All Ireland Pollinator Plan has over 180 actions, the first of which examines ways to make farmland more pollinator friendly.

There are five evidence-based actions which farmers can incorporate into their holding to improve conditions for the vital insects:

  • Maintain native flowering hedgerows;
  • Allow wildflowers to grow around the farm;
  • Provide nesting places for wild bees;
  • Minimise artificial fertiliser use;
  • Reduce pesticide inputs.

Wilson said that a lot of her work with farmers involves promoting native hedgerows, trees and shrubs.

“Farmers are very open to hearing that, they love getting information. They are very keen to hear about our native wildflowers, trees and shrubs.

“I always say that if you can, step back from the hedge a bit and leave an area there, as that is where the bumblebees might be nesting and overwintering.

“It’s very simple action, you just have to not cut as much, but cut and lift once a year is wonderful.

“Insects like the hoverflies are also so valuable and are natural predators. So they are very good for aphid control,” she said.

Cavity nesting solitary bee nest. Image: Ruth Wilson

So where do pollinators go during the winter months?

“Generally, they are tucked away I would say. It’s not a good time of the year to be out. It can get frosty, chilly and very wet which they won’t like and of course there’s a lot less wildflowers in the landscape.

“For the bumblebee, it is just the queen that is left at the end of the season. That’s the last bumblebee you’d see flying around. She’s very big and she looks perfect. She’s just hatched out.

“She will gorge herself as she can and overwinter under soil, under soil or something like that.

“Then for the solitary bees, some nest in the ground and some nest in cavities. Some will be adults and some will be really small larvae,” Wilson said.

The lifecycle of hoverflies varies between species and depends on environmental conditions and the availability of food.

The insects will either hide in soil as larvae or hibernate as adults in nooks and crannies.