New Zealand's agricultural sector stands to lose up to $700 million a year if bee numbers continue to fall, according to a new study.
Beehives have been declining in numbers across the world in recent years, including New Zealand, in a process known as colony collapse disorder (CCD). It's not yet known what's behind CCD.
Rather than calculate the financial impact using "desktop calculations around the value of crops and the dependency of those crops on pollinators", researchers at Lincoln University instead went out to commercial fields and covered some of the plants, to see what impact it had in seed yields and fertilisation.
The results were then extrapolated New Zealand-wide - between $295 million and $728 million a year in lost production.
Professor Stephen Wratten says intensive agriculture is having the greatest impact, and we need reinstate bee-friendly orchards.
"Hedges are taken out and there's higher weedkiller use. It means that those weeds that flower and provide nectar and pollen to bees are very rare now."
Professor Wratten fears many consumers won't notice until it hits them in the pocket.
"I think they'll understand it more clearly when the price of apples in supermarkets goes up 50 percent - or oranges or mandarins or satsumas or peaches or apricots or cherries. That's when it hits home, really."
Eighteen different crops were used in the calculation.
Prof Wratten says though CCD is still a mystery, scientists are closing in on ways to fight it - but this knowledge is useless if it doesn't reach farmers.
"There is a lot of scientific knowledge accumulating but this has to be turned into 'recipes' for end users like farmers to understand and implement.
"The big challenge is to have a recipe that works. Give farmers the right seeds to plant. Make sure the bees get what they need. It's not about planting pretty flowers - it's the science that counts."
"The best way to deliver this is through what we might call 'farmer teachers' - farmers who understand and use the recipe, who will get out into the paddock and be listened to by other farmers."