A new gold fever has struck California - but this time it's almonds, not nuggets. On a surface area twice the size of Belgium in the state's central valley a huge agricultural zone produces around 82% of the world's almonds, an industry worth billions. Demand for the humble almond is booming, especially from China and India where it is considered a healthy, non-fattening source of high energy food. Because of this rising demand, the price of almonds has doubled over the past five years and many valley farmers have dug up their fields and planted young almond trees.
To grow almonds effectively, however, you need water - lots of water - and pollinators. Providing the latter is an army of bee keepers from across the United States who transport around 1.5 million bee colonies, or approximately 70 billion bees, to California to let them loose on the almond orchards. The annual ritual draws bee keepers from as far away as Maine and Massachusetts since the fee per colony - at $ 180 - makes even a long journey across the US a worthwhile venture. Many of the bee keepers own several thousand colonies and can make a tidy sum during pollination season.
Pollination by bees is far more efficient than by wind, which has kept demand for bee pollination up over the past years. Yet since 2006, an unexplained malady is affecting America's bees with scientists divided over the reason for their plight. In that year, American bee keepers lost half of their colonies. Since then they've tried to rebuild but year after year, the bees keep dying - 42% of them in the last winter.
Some blame so called Colony Collapse Disorder (CCD) for the catastrophic death rates of their colonies. This phenomenon sees hives completely deserted, with only a few dead and dying bees left after the winter. The causes of CCD are unclear but may include the varroa mite (or varroa destructor), a parasite that sucks the body liquids out of bees and their larvae the use of powerful neonicotinoids as insecticides. Some believe that the spread of monocultures is depriving bees of sufficient food.
Many beekeepers have given up their trade and bee colonies are now in short supply. Scientists are experimenting with solitary bees who live in cooler climates and don't live in hives but capturing them in cooler climes, shipping them in cooled transportation and then keeping them in refrigerated 'bee hotels' until the next season is an expensive undertaking. The solitary bee is far away from being numerous and affordable enough to replace the honey bee.
California's almond growers face another challenge: water shortage. The state is experiencing the worst drought in 90 years are city dwellers are increasingly hostile toward an industry that consumes 8% of the state's water resources - more than the amount of water used by San Francisco and Los Angeles combined. Many wonder why they are being asked to cut down on water usage while almond growers get unlimited amounts to grow a crop that is mainly for export.
Dieter Telemans, a beekeeper in his native Belgium himself, travelled to California to witness this vast migration and to document an industry that is under pressure from different directions.