In recent years, bee colonies have died out in alarming numbers, and environmental and public health agencies have striven to discover the underlying causes and implement policies that will reverse the phenomenon, which has become known as Colony Collapse Disorder (CCD). Can cannabis growers help to solve the problem? Read on.
Are bees attracted to cannabis plants?
Generally, bees will are attracted to flowers that are good producers of both nectar and pollen, and will reject flowers that are insufficiently rewarding. In turn, flowers that require insect pollination have generally evolved to produce sufficient nectar to attract bees and other insect pollinators.
Bees are not attracted to cannabis in normal times as it is a wind-pollinated plant and therefore has no need of nectar to attract insect pollinators. But during times of “floral dearth”, when nectar-producing flowers are absent, cannabis flowers can become an important source of pollen. Bees require pollen in order to produce royal jelly, and also glean hugely important proteins, vitamins and minerals from it.
A study conducted in Punjab, India and published in 2012 showed that during a floral dearth period (in Punjab, this occurs in May and June), honey bees (Apis mellifera) turned to the abundant male cannabis plants growing wild in the region as a pollen source. As cannabis flowers do not produce nectar, the bees that were observed feeding on the plants were specialized pollen-gatherers only.
Furthermore, bees were observed feeding on male flowers only during mornings and evenings, and were absent at other times. This is due to the fact that anther dehiscence—the process whereby the male reproductive organs split to release pollen—occurs during these times. Thus, bees are attracted to cannabis plants, but only to males, only during floral dearth periods, and only during periods of peak pollen production.
What is colony collapse disorder?
The phenomenon of colony collapse disorder is characterized by the majority of mature worker bees abandoning the hive, leaving behind the queen and her immature brood—along with plenty of food, and some nurse bees to care for them. That the workers abandon the hive is key—in cases of CCD, no build-up of dead or dying bees is observed around the hive.
This bizarre and intriguing phenomenon has occurred throughout history, and has been known by a variety of names including “spring dwindle” and the “disappearing disease”. In Ireland, “a great mortality of bees” was recorded in 950 CE, and again in 992 and 1443. However, it appears that the frequency and severity of these collapses has been increasing over the past century, and whereas previous collapses would occur in relative isolation, seasonal bee losses are now significantly higher than expected every year. In 2007, some American beekeepers experienced 80-100% losses; ‘normal’ losses are considered to be around 10%.
CCD has been attributed to a variety of factors including viral or parasitical infections, in-hive chemicals used to treat the bees, genetically-modified crops, monoculture, general reduction in plant biodiversity, nutritional stress, and pesticide use. While no one factor has been proven to be responsible (and some, such as GM crops, are not thought to contribute greatly, as areas with large-scale cultivation of such crops are not correlated with high levels of CCD), it is likely that a combination of factors is contributing to the overall ill-health of bee colonies worldwide.
Floral dearth period and CCD
During floral dearth periods, commercial beekeepers often supplement their bees’ diet with high-fructose corn syrup or sugar syrup with added protein. Interestingly, research has shown that bees fed on simple sugar syrup made from sucrose produce more brood in spring than bees fed on HFCS; furthermore, supplemental protein led to higher brood numbers but did not provide the young with complete nutrition.
Thus, beekeepers should supplement their bees’ diet with sugar syrup made from sucrose during floral dearth periods, and should supply them with a more nutritionally-complete source of protein than that provided by supplements. Pollen from cannabis or hemp, or similar species that flower at the appropriate times, would be an ideal way to provide bees with the complete profile of amino acids required to synthesize protein, along with a healthy mixture of vitamins and minerals.
Pesticide use and CCD
The role of pesticides in CCD is controversial and mired in political obfuscation. There are arguments for pesticides having a major role, but there are also compelling counter-arguments suggesting that another, as-yet-unknown factor must also be in play, and that the role of pesticides is supplementary at most. Neonicotinoids, for example—a class of pesticide often associated with CCD—are used as extensively in Australia as elsewhere, but Australia has experienced no significant decline in honey bee numbers.
However, Australian bees have traditionally acquired their pollen from natural, unsprayed plant sources, rather than from commercial crops. As beekeeping in Australia shifts from honey production to pollination of commercial monoculture crops such as almonds (already a common practice in the U.S.), bees there will be subject not only to the nutritional stress caused by prolonged feeding on a single food source but also to increased levels of agricultural chemicals including neonicotinoids.
There is also abundant evidence to suggest that several classes of pesticides and fungicides (including but not limited to neonicotinoids) that are currently used in combination may have a range of sub-lethal effects on bees, including feeding and reproductive behaviour. Furthermore, even a commonly-used organic pesticide, neem oil, has recently been implicated as a potential contributor to CCD.
Neem oil and bumblebee colony collapse
Azadirachtin, the active compound in neem oil, is a fundamentally important pesticide in organic farming, and selectively attacks various pests that cannot be controlled otherwise; however, a recent study concluded that male bumblebees were negatively affected “even at concentrations 50 times lower than the recommended levels used by farmers”.
At recommended levels, no males hatched in laboratory colonies; even at 50 times lower, the few males that hatched were deformed.
Previous research has indicated that neem oil is generally safe for honey bees, but bumblebees are nonetheless highly important pollinators of crops and wildflowers. Furthermore, use of any substance that threatens biodiversity should be avoided at all costs, as the ongoing loss of plant and animal species throughout the planet is now being seen as the Earth’s sixth mass extinction event; threatening the existence of pollinator species, who by their very nature are depended upon for the survival of various plant species, is particularly unwise.
Ensuring your cannabis is bee-friendly
As we have seen, during the floral dearth period, bees may be attracted to cannabis plants. Although far more likely to target male plants, they may also visit females due to similarities in aroma. However, only male cannabis plants can act as a food source for bees. Thus, growers who keep male plants outdoors (or hemp growers, wh0 tend to grow male plants as standard) may be providing an invaluable service to local bee populations during floral dearth periods.
Pesticides used on cannabis, even organic pesticides such as neem, may contribute to CCD in honey bees and bumblebees. Thus, outdoor plants, whether male or female, should wherever possible be managed with non-chemical methods of insect control. Beneficial insects, nematodes, enzymes and so on can all play a part in keeping plants pest-free without the need to resort to chemical sprays, even those with organic credentials.
Cannabis growers can do nothing about the main contributing factors to CCD, which are likely to be related to large-scale agricultural monoculture of insect-pollinated crops, along with the habitat fragmentation, loss of biodiversity and increased use of chemicals that goes with such a system. However, as a community we can ensure that we do the maximum to ensure that our contribution to CCD is minimal or non-existent, and by growing hemp or male cannabis outdoors, we may even help to alleviate the problem to some extent.