The QFF Lifecycle

The Lifecycle of Queensland Fruit Fly

Queensland Fruit Fly can complete it’s lifecycle in 28-32 days on average. Warmer climate and ideal conditions can accelerate this process as does cooler weather making the process take longer.

ADULT

The QFF adult spends it’s day in the tree tops and on the bush floor eating naturally occurring proteins and sugars. The flies feed in the morning, rest during the heat of the day, and feed again in the evening to prepare for their evening rituals.

    QLD Fruit Fly

    QFF adult, credit Deb Yarrow 

    MATING

    The female QFF is attracted to the male “lek”, a group of several male QFF in the tree tops that forms when the temperature is 15 deg C. or warmer at sunset. They all release pheromones to attract the female. She will choose one or many males on these occasions.

    The male spends his day preparing for this mating event by sleeping, eating, searching for and consuming a para pheromone that he later uses to make his own pheromone for attracting the female QFF.

      QFF mating, credit Ajay Narendra

      QFF mating, credit Ajay Narendra

      Queensland Fruit Fly

      QFF eggs in fruit, credit Agriculture Victoria and NSW DPI

      EGG LAYING

      Once mating has occurred, the female QFF can store the male sperm for later use. The eggs are fertilised and she seeks out fruit that is turning from green/underripe to coloured/ripe. This is her plan so that her babies mature at the same rate as the fruit ripens. Hanging fruit is preferred in comparison to fallen fruit, however in times of high QFF population, fallen fruit can be sought by desperate female QFF. 

      LARVAE

      Once the larvae hatch from the egg, microbes assist the fruit flesh to rot and decompose. The larvae eat the fruit jelly with it’s two narrow jaws. As the larvae mature they go through three instars (stages of development). Once they are mature larvae, they make their way to the outside of the fruit to escape the rotting fruit environment.

      FRUIT DROP

      As the fruit drops to the ground, the larvae sense the thud on the ground and promptly exit the fruit. From the day they were eggs to now was timed by nature to be co-ordinated! Longer development time can be associated with colder weather. The larvae once on the ground can jump or skip by placing head to tail then leaping or flicking their bodies out of danger (predators and the elements)

      QFF larvae in peaches

      QFF eggs in fruit, credit Agriculture Victoria and NSW DPI

      PUPAE

      The larvae digs into the soft mulch, ground cover and soil.

      In the safety of the ground (or corflute cardboard box or grove in the timber) the larvae’s skin layer hardens to form a pupae case. Inside, over about a week-10 days (plus or minus depending on temperature and conditions) the larvae morphs into a fly.

      QFF pupae, credit NSW DPI

      QFF eggs in fruit, credit Agriculture Victoria and NSW DPI

      EMERGENCE

      Once the fly is ready to leave the pupae case it breaks it open at the top and tunnels to the surface. This happens best when the soil or medium has sufficient moisture and is common to occur after rain. The newly emerged fly dries out their wings and flies off to look for food, water and shelter.

      Newly Emerged FF on Apricot

      MATURING

      Each fly needs sugar, water and protein to survive and mature. Like a child and then a teen, the fly needs to eat proteins to sexually mature. This takes about 10 days (shorter or longer depending on temperature and conditions). Once mature, the flies are ready to mate and the cycle starts again.

      Mature QFF edited