Honey bees are essential for the pollination of flowers, fruits and vegetables, and support about $20 billion worth of crop production in the U.S. annually, Matthew Mulica, senior project manager at the Keystone Policy Center, a consulting company that works with the Honey Bee Health Coalition, told ABC News.

Campaigners have handed in a letter to the Minister for Agriculture, Michael Creed, calling on him to support the banning of more pesticides which harm the bee population. The European Commission has already banned three pesticides because of their impact on the declining bee population, but campaigners want the commission to go further.

The global grassroots organization Slow Food was among the groups that called for far greater attention by world leaders to the "debilitating" loss of biodiversity and the disastrous effects the decline is having on food system, which was outlined in a first-of-its kind report by the Food and Agriculture Organization of the United Nations (FAO).

Buying organic food is among the actions people can take to curb the global decline in insects, according to leading scientists. Urging political action to slash pesticide use on conventional farms is another, say environmentalists.