"If the bees are in trouble, so are we," says Jack Stone as he tends to a beehive on the rooftop of a cafe in Brisbane.

Mr Stone is one of the growing number of 'urban apiarists' around the world working to improve the plight of the bee, whose numbers have been in sharp decline for the past 10 to 15 years.

"We currently have 15 hives in place around Brisbane," says Jack, owner and operator of Bee One Third, a Brisbane company placing and maintaining beehives in urban locations.

"And we have a waiting list that includes a number of schools looking to integrate the teachings of bee literacy into their curriculum."

The increase in urban beehives around the world started at the same time as the first reports of declining bee numbers.

No one city is credited with having given birth to the popularity of beehives, although London saw a 220 per cent increase in beekeepers between 1999 and 2012 and now hosts around 3,200 hives.

New York City follows with around 400 and hives can be found in other international cities, including Paris, San Francisco, Hong Kong, Honolulu, Shanghai and Toronto.

Australian cities have also come onboard and Brisbane, Sydney, Melbourne and Adelaide now host beehives.

Many of these hives can be found on rooftops, where bees are able to go about their business out of sight, out of mind for the city-dwellers living around them.

"Bees are actually quite harmless," Mr Stone said.

"Their job is to gather nectar and make honey and they'll only sting you if they think you're going to harm them.

A bee smoker sits on a rooftop beehive before being used. ( ABC News: Giulio Saggin )

"If one does buzz around you, gently wave it away with your hand."

Australian city-dwellers are learning to embrace the bee and the idea of having a hive 'upstairs' is becoming more and more popular.

"We started out three years ago and now have 70 beehives around Melbourne," Melbourne City Rooftop Honey's Vanessa Kwiatkowski said.

"Sixteen of these are in the CBD, including 10 on the rooftop of Federation Square.

"We have around 400 people and businesses interested in either sponsoring or adopting a hive.

"We're taking on another person next year to help deal with the demand."

The same is happening in other Australian cities hosting beehives.

CBD Bees started in Adelaide just over a year ago after Linda Walker and Sandra Ullrich met at a beekeeping course.

"We started out wanting to have 10 hives in place within the first year," Ms Ullrich said.

"We recently marked our one-year anniversary with 20 hives in place, including on top of the Adelaide Zoo."

Beehive clientele vary but it is more popular among cafes and restaurants.

Doug Purdie, from the Urban Beehive in Sydney, says about half their hives are in place with food-related businesses.

"Many of our clients are interested in using local product and keeping the food miles down," he said.

A big advantage of having a beehive or beehives close by is the availability of clean, pure honey."

The Gunshop Cafe, owned by Jason Coolen in Brisbane's West End, has two beehives on its roof.

"The flavour you get from our honey is unbelievable," he said.

"The amazing thing is the honey from the two hives is completely different, even though they are side by side."

Bees crawl over an egg-laying frame. ( ABC News: Giulio Saggin )

Scott McCutcheon from the Downtown Honey Co in Brisbane says the differences in the honey come from where the bees choose to forage.

"Bees forage different locations and plants, even if the hives are next to each other," Mr McCutcheon said.

"Honey changes depending on the time of the year and what plants are flowering.

"When the jacarandas are in bloom each spring, the honey is translucent and sweet, almost like maple syrup.

"But in late autumn, when many plants have stopped flowering, the honey has a distinct eucalypt taste."

Bees forage up to five kilometres from their hive, so they relish the greater diversity of plants spread throughout suburban gardens, many of which have not been subjected to pesticides.

Ms Kwiatkowski cites one example:

"Honey from beehives in Paris have been analysed and more than 250 different pollens were discovered, whereas 15 or 20 pollens can be found in honey from rural hives," she said.

Bees disappearing worldwide

Bees are responsible for pollinating more than 70 per cent of crop species, worth $30 billion a year, that supply the world with 90 per cent of its food.

In 2010, a federal government report stated that about 65 per cent of agricultural production in Australia, including 35 industries, depends on pollination by European honey bees.

As a result, the decline in bee populations worldwide are of great concern.

In 2006, some beekeepers in the USA reported the sudden, unexplained disappearance of their bees, with no dead bodies found near the hives.

This phenomenon resulted in hive losses of 30-90 per cent and was given the name colony collapse disorder (CCD).

Since 2006, bee numbers have dropped at an alarming rate and beekeepers across Europe and the USA have reported annual hive losses of 30 per cent or higher.

The reason behind CCD is still unknown, but many causes have been put forward, including human impact on the environment - habitat loss, pesticides, monoculture and climate change - and, possibly, the most destructive, the varroa destructor mite.

According to the Australian Department of Agriculture, varroa mites are "external parasites of bees that are about the size of a pinhead, use specialised mouthparts to attack developing bee larvae or adult bees, resulting in deformed bees, reduced lifespan and ultimately the destruction of the colony or hive".

Australia is the only country in the world without the varroa mite and CCD, so the bee population is still relatively healthy.

"But many say it is only a matter of time before varroa gets here," Mr Stone said.

Beekeepers, scientists and the agricultural industry across Australia hope this isn't the case.