They clumsily bang against our windows and make themselves a springtime nuisance - but the humble bumblebee could prove more valuable to New Zealand's economy than we ever imagined, researchers say.
The furry foragers are increasingly being eyed as pollinators in orchards, with the potential to make a significant contribution alongside honeybees.
Scientists at Plant and Food Research are analysing the earliest findings of a six-year programme which has established hundreds of nest boxes in New Zealand orchards.
Of those set up in Bay of Plenty avocado orchards, about 30 per cent have been occupied by queen bees, considered a highly successful rate.
"In the future, I would hope to see bumblebees become as commonly used as honeybees to increase pollination in orchards," Plant and Food Research scientist Dr David Pattemore said.
For orchardists trying to boost production by increasing pollination rates, bumblebees were appealing. Producers traditionally used honeybees to pollinate their flowers, but rental charges were growing as beekeepers had to spend more to manage their bees in the face of the destructive varroa mite. Dr Pattemore said that bumblebees were not vulnerable to varroa, were more effective at cross-pollination and didn't mind working in the often cold, wet and windy spring weather.
"Honeybees, being a very large colony of 60,000 individuals, have got a real tight division of labour, and each individual bee is very specific to what type of flowers they visit."
"Whereas bumblebees are less specific, they don't have such a specific colony structure and just go out and individually forage."
Further, international studies had shown increased competition between bees meant more movement, which in turn meant better pollination. The problem, he said, had been that not enough was known about bumblebees.
Dr Pattemore said the research programme, in trial orchards in five test regions and being funded by the Government and industry groups, had already come some way in solving some of the big mysteries.
So far, queens seemed to prefer nest sites in banks over flat ground.
"It will be quite exciting to see what results we get in the next few years."
5 reasons bumblebees are top pollinators
1 According to Biobees, a company specialising in bumblebee pollination, bumblebees can forage in windy, low-light and drizzly weather and at temperatures as low as 5C. In these conditions, honeybees tend to stay home.
2 Their large size and hairy bodies mean they can collect larger quantities of pollen. It's estimated a single bumblebee can do the work of 50 honeybees, meaning fewer bees are required.
3 They perform "buzz pollination", a technique used to free pollen from anthers, which is particularly important for tomatoes, potatoes and eggplants.
4 Rather than visit certain types of flowers as honeybees do, bumblebees will fly between many and of both sexes, increasing pollination.
5 Research has shown that having more competition between different species boosts pollination and thus production.