Preference for some colours over others is often thought to be a part of human personality. However, human beings are not the only species to have a preferred hue. Many insects including flies do show a preference for some specific shades of coloured light over others, and this is taken into account while designing a fly light trap.   

Karl von Frisch, a German Nobel prize winner, first described colour vision in honeybee over 100 years ago.  Later on, other researchers found out that many other insects are capable of perceiving colours. In fact, many of them including flies have their own favourite colours that affect their behaviour. For example, given a chance, rather than green light, flies move towards light in the ultraviolet (UV) spectrum. 

As you may already know, light travels as wave, in the form of a series of peaks and troughs. The colour of the light is determined by the distance between two adjacent peaks, which is commonly referred to as the wavelength. Ultraviolet (UV-A) light has a wavelength of less than 400 nm and is visible to flies but invisible to humans. 

When light enters the eye, it gets absorbed by a specific type of photoreceptor. When the light hits these photoreceptors, a series of reactions are triggered to send signals throughout the brain. The brain turns these signals into colour vision by compiling and comparing information from the photoreceptors. Organisms are able to see in colour because of comparisons across the photoreceptors. Most of the fly species have two types of photoreceptors. 

How Flies are Drawn to UV-A

Neuroscientists suggest that sensory perceptions are somewhat similar to ladders. Something new is added to the perception while passing through each level of processing in the brain. Most of the living beings perceive their surroundings through this multi-level, hierarchical process. However, flies also have an additional hardwired escape reflex that gets triggered by their favourite colours. Moreover, according to recent studies, there is a special brain circuit in flies that guides them toward UV-A light. The two different photoreceptors found in flies are tuned to slightly different wavelengths in the UV-A spectrum. Their photoreceptors, identify these different colours. Other information is trafficked into a colour-blind pathway. 

The propensity of flies to be drawn towards UV-A light forms the foundation of designing modern-day electronic fly killer light traps. These traps are available in a variety of shapes and sizes including wall mount, ceiling mount, wall sconce, freestanding, etc. Insect light traps are used extensively in commercial settings such as hospitals, restaurants, food processing facilities, and many other areas to achieve a fly-free environment.

At Vectothor, we offer UV-A light output optimised fly light traps that match the vision spectrum of houseflies perfectly. These traps are CE-approved, RoHS Standards compliant (Removal of Hazardous Substances), and approved for use in HACCP approved food facilities. 

To enjoy the benefits of a fly-free work environment, please contact our expert exterminators today.