Bee Aware

by Jordan Pennells

In the same way that cows are considered sacred in the Hinduist faith and the Dothraki worship their horse companions, the Australian Honey Bee is worthy of this honour! Not only is it one of my favourite animals, their presence contributes significantly to the sustainability of the environment and the global community in a range of ways. The importance of the Honey Bee to our daily lives is not to be underestimated!

So what function does the Honey Bee have within the web of nature, and how does this role disseminate throughout the world? Certainly, the introduction or removal of any animal from its ecosystem will result in a significant disruption. This is evidenced firstly by the introduction and domination of cane toads within Australia in an attempt to eradicate the destructive cane beetles, or the removal of apex predators causing a host of negative, and sometimes unforeseen, flow-on effects. It has been theorised that the (predominantly) Japanese whaling industry in the 20th century has led to such a loss in great whale numbers, that an estimated 105 million tonnes of sequestered Carbon, that would have settled to the bottom of the ocean in the form of whale faeces, is instead now present in the atmosphere as CO2, contributing to climate change.

However, the effect from the disappearance of bees would be arguably more dramatic. Not only do they produce between 20,000-30,000 tonnes of honey in Australia annually, they are the most indispensable pollinators in a world in which one third of all food consumed by humans is pollination dependent. The key features that allow a colony of up to 50,000 bees to produce up to 27kg of honey per season (on top of for their own personal use) include their amazing flying ability, highly organised behaviour and keen sense of smell.

The cult classic Bee Movie opens with:

According to all known laws of aviation, there is no way a bee should be able to fly. It’s wings are too small to get its fat little body off the ground.

Despite being taken as gospel by many people, it has been proven as a myth that bees shouldn’t be able to fly. The misconception is speculated to have began at a ‘raging’ party attended by scientists and engineers. An entomologist quizzed drunk engineers about the fluid dynamics involved in insect flight. The engineers took the chance to show off their mathematical abilities, formulating a series of equations with assumptions that counter-intuitively revealed that, according to physics, bees shouldn’t be able to fly. As confident as drunk engineers can be, it had multiple flawed assumptions that led to this conclusion.

The most important of these incorrect assumptions was that bees employ the same flight technique as airplanes, which create a lift force by pushing air downwards. In fact, bees beat their wings, which are slightly tilted at an angle as to catch the wind, in a similar fashion to a helicopter propeller. This technique forms eddies of low pressure air above their wings, creating an upward force allowing for them to remain in flight.

honeybee-streamline-model

Computational flow-field model of the Honeybee flight technique

This flying ability allows bees to travel up to a 10 km radius from their hive to source their honey-producing nectar, but this is not the only feature that contributes to their success.

As if from a feminist’s pipedream, worker bees are solely female with specialised physiology that allow them to collect nectar and pollen, while the male drone bees linger in the hive without providing any useful work for the colony, with exception to occasionally mating with a queen of another colony. Female worker bees recognise this discrepancy in contribution towards the success of the hive between genders, which is exacerbated by the fact that drone bees eat three times as much food as the worker bees. At a time when stress is placed on food supply for the colony, such as nectar and pollen resources dropping when winter is coming, the drone bees are expelled from the hive and left outside to starve. This organisation lends itself to the construction and maintenance of a complex nest structure, a coordinated defense when the hive is under threat and inter-bee communication.

Bee communication includes both behavioural traits and pheromone signalling. The Waggle dance is not a new hit song from The Wiggles. Instead, it is an ingenious form of communication that the forager bees use to explain to the rest of the colony where new food sources can be found. The dance is performed in a figure-8 manner, with the angle at which the bee doubles back corresponding to the position of the food source relative to the ultra-violet light of the sun (the YouTube hyperlink gives a much better explanation, or if you just want to see a bee twerking).

bee-dance

The Waggle dance as communication between forager and recruit bees

Concurrently, dancing bees release a profile of 4 semiochemical pheromones (signalling chemicals), that motivate the recruitment of other bees to leave the hive.

Pheromones are an imperative communication device that bees have adapted to alert others within their vast community of changes in environmental conditions or imminent threats to the hive. Bee’s antennae,  are so sensitive that they can detect volatile chemicals in the air at a concentration in the range of parts per trillion. Upon identification of this fact, researchers attempted to harness this ability to train bees to become the next explosives-detection animals.

bee antenna.PNG

Microscopic image of a Honeybee antennae magnified 150x

If you aren’t yet convinced by how cool bees are, just have a look at the food they produce for us. Honey can legitimately be called a superfood. It is assumed to be able to be preserved forever, after it was discovered in a 3,500 year old Egyptian tomb and was found by paleontologists (with much risk) to be perfectly edible. The science behind the amazing preservation properties of honey can be attributed to its low pH of around 3-4.5, and the maintenance of its naturally low moisture content when stored in an airtight container. These conditions prevent the survival and proliferation of bacteria, through the acidic condition stripping microorganisms of their electrons, whilst low moisture content leaches water from the bacteria through osmosis. Past civilisations, such as the Ancient Egyptians, recognised these seemingly magical properties of honey and used it as an antiseptic ointment for skin and eye conditions.

The case for the classification of honey as a superfood comes in the form of a swathe of research evidence. Ajibola et al compiled a review of this evidence, highlighting that honey has a range of health benefits that include:

  1. Haematology – enhance blood profile; increased haemoglobin concentration erythrocyte count and haematocrit levels.
  2. Immune – enhanced immune response; higher lymphocyte and neutrophil count.
  3. Oral Health – prevention of dental plaque, gingivitis and periodontitis.
  4. Gastroenterology – Honey contains prebiotics (substances that facilitate the enhanced growth and biological activity of beneficial bacteria in the gut). It has been shown to be a gastroprotective agent, with anecdotal evidence suggesting treatment of ulcers, gastritis and gastroenteritis.
  5. Ophthalmology – success of human clinical trials using natural honey for patients with eye disorders not responding to conventional treatment confirms the well documented practises of ancient societies using honey remedies for eye problems.
  6. Cardiovascular – ameliorates risk factors of metabolic and cardiovascular diseases.
  7. Wound Healing – due to antiseptic properties of honey.
  8. Antimicrobial activity – potent broad spectrum antibiotic.

(Note: predominantly based on rat model studies)

Despite bees best efforts with their advanced communication techniques, a threat to Australian Honey Bee colonies that is causing conniptions amongst apiarists is the Varroa mite (with the apt scientific name of Varroa destructor). This parasite hitches a ride on their host, the Asian Honey Bee, which are immune to its devastating effects through their synergistic evolutionary history.

Upon infestation, mites feed on larvae and also increase the rate of deformity in maturing bees, causing the colony to collapse and die within 3-4 years. Whilst the Varroa mite has previously wreaked havoc upon bees and the honey community in parts of Europe, it has not been sighted within Australia.

…. Until very recently.

Biosecurity Queensland has put the Far North under lockdown after the discovery of Varroa-supporting Asian Honeybees in the Port of Townsville mid way through 2016, with the culprit bees assumed to have been accidentally imported into the country in a shipping container.

The spread of the Varroa mite would not only devastate bee and honey lovers everywhere, but would spell widespread economic disaster for pollination-dependent food stocks and all related industries.

The message that the Government Department of Agriculture and Fisheries is sending the general public to stop the spread of the deadly Varroa mite:

“Bee aware”.

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