Let’s get curious and ask ‘do bees fly at night?’ and ‘can bees see in the dark?’! But…what do we actually mean by ‘night’ and ‘dark’?
A creature may be nocturnal in its habits (active at night 🌔), crepuscular (active during dusk and dawn 🌅) or diurnal (active during the day 🌞).
While most bees are diurnal, there are a few exceptions with a small number of bees being crepuscular or even nocturnal. They actively forage for food, and have evolved the ability to see and fly in the dark.
As far as we are aware, nocturnal or crepuscular bees are mainly tropical species. Interestingly, a number of tropical wasp species have also evolved this lifestyle. Such bees (and wasps) are able to fly and navigate through a dark forest between their nest and target foraging site. There are however significantly more crepuscular bee species rather than nocturnal ones, and either way, all these bees still need some light, just that they can function lower levels of it compared to their day light friends. So at least some moonlight is necessary.
Bees have 5 eyes in total. Two compound eyes, which are made up of many hexagonal facets, meaning that they can simultaneously see all around them – above, below, side to side, and forwards… and three simple eyes, or ocelli, which are 3 eyes positioned on top of the head. These eyes are sensitive to light and aid the bee in its orientation. In night flying bees, the limited amount of light available, has resulted in the evolution of proportionately larger eyes overall. In particular, the three ocelli (which are more sensitive to light) are much larger.
Picture from the Bee Aware Brisbane blog page
But what is the point of these bees being active at night or in the dark? Here are some of the reasons why:
Pressures from predators and parasites
Bees foraging at night are less susceptible to attack from predators and parasites.
Competition for limited food sources
There is less competition for food. Bats and moths are the only notable competitors at night time.
Flowering patterns of local habitat in tropical regions
Some flowers only open at night, while some produce nectar both during the day and at night.
Some of the bees may live in dry environments, and flying during the colder morning and evening hours minimizes their loss of water.
Ultimately, I think people often forget to be curious about the world around them and don’t ask themselves questions such as ‘are bees active at night?’ – but hey, I went ahead and asked it for us all! Now we know that some of our little pollinating friends are indeed up until late.