‘Severe decline in bee species threatens food security worldwide’

At a time when many managed and wild-bee species are in a severe decline that threatens food security, researchers from Athlone Institute of Technology (AIT) and Maynooth University have joined forces with the University of Minnesota, in the US, to tackle diseases affecting pollinators.

Prof. Neil Rowan from AIT and Dr. Michael Goblirsch from the University of Minnesota are collaborating by looking at the specific use of enabling disruptive technologies.

This includes the novel treatment of pollen that may harbour complex parasites and viruses as a critical control point for treating and preventing their spread or cross-transmission to honeybee and bumblebee species.

Agriculture fellowship

The trans-disciplinary research is supported by an OECD (Organisation for Economic Co-operation and Development)  CRP (co-operative research programme) agriculture fellowship and by an EPA (Environmental Protection Agency) co-funded PhD.

The research also acts as innovation platform to unite with Dr. James Carolan of University of Maynooth in co-investigating the impact of such interventions and approaches on bee immunity and health.

The foundation of the work arose from frontier studies undertaken by Prof. Rowan with John Naughton, an MSc graduate from AIT, Dr. Erin Jo Tiedeken, formerly a post-doctoral researcher AIT and now at the University of New Jersey, and Prof. Jane Stout of Trinity College Dublin that was published in a leading agriculture journal.

This applied innovation project is also framed to complement other pollination-based projects affecting agriculture and ecosystem service management – such as the recent H2020 PoshBee project.

Flowering crops

“Animal pollinators are critical for food security and ecosystem servicing that ensures the reproduction of the majority of wild flowering plants, as well as most flowering crops,” said Prof. Rowan who is director of the Bioscience Research Institute at AIT.

87 of the main 124 crops used directly for human consumption require or benefit from animal pollination annually. Pollinator services contribute €153 billion and €54 million to the global and Irish economies respectively.

“Wild bees are often the most effective animal pollinators. However, domestic honeybees have been introduced worldwide for commercial crop pollination. In the 1980s commercial rearing and importation of bumblebee colonies for pollination of certain crops began,” said Prof. Rowan.

Today, commercial bumblebee colonies are imported by over 50 countries and the practice has an estimated annual value of €55 million.

However, many managed and wild-bee species are in severe decline that threatens food security worldwide.

“More than half of Ireland’s bee species have experienced substantial declines since the 1980s, so this issue is of great national concern – evidenced by the recent publication of the All-Ireland Pollinator Plan.

“A critical contributing factor to pollinator decline is an increase in the spread of a broad range of parasites, including mites, protozoans, bacteria, fungi and viruses. Some parasites appear to be host-specific but most appear to infect multiple bee species.

“The host range, natural geographic range and virulence in different bee hosts are poorly understood for bee parasites. That reflects in part the absence of effective mitigation strategies to address this significant problem,” Prof. Rowan said.

Serious concern

He highlighted that there is also considerable concern that the or human-influenced movement of managed bees for crop pollination purposes has led to the accidental introduction of bee parasites into countries and continents where they do not naturally occur.

“This exposes native bees to parasites which may have little resistance,” he said.

“Parasites can move between managed or commercial colonies and can even spill over into conspecific wild bee populations that is a serious concern.

It was pointed out that such disease associations have already occurred between managed and wild bees, both in the UK and Ireland.

73.5% of screened commercial bumblebee colonies imported to Ireland were infected with a least one harmful parasite.

“Mitigation measures that reduce parasite loads among managed bees must therefore be developed and implemented in order to protect wild bee populations,” Prof. Rowan stressed.

He highted that “multiple stressors” – such as exposure to pesticides – affect honeybee and bumblebee health, well-being and pollination functionality.

“Uncertainty brought on by large variances in climate change may contribute significantly to this problem,” he said.

Appeal to farmers

Recently Juanita Browne, All-Ireland pollinator plan project officer, expressed concern about the continuing decline of the Irish bumblebee populations.

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