Mushroom Fly Behavior
Understanding the natural history and biology of an insect is an integral part of characterizing it's behavior. Once we've characterized mushroom fly behavior in the laboratory and on mushroom farms, we will identify behaviors that are susceptible to manipulation, and incorporate these manipulations into Integrated Pest Management (IPM) strategies.
The Mushroom Growing/
Fly Development Complex
Because of how closely fly development is associated with the mushroom growing cycle, both will be presented as a single complex:
Sciarid Eggs
Mushroom Phorid Egg
Spawn Run Compost
Sciarid Eggs
Oviposition
Mushroom fly adults lay eggs in the mushroom compost during "Spawn Run". This is when the mushroom mycelia (like the "roots" of the mushroom) are actively growing. One female fly can lay over 50 eggs!
Larval development
Eggs hatch in 2-3 days and larvae develop in the maturing mushroom compost (Spawn Run). Mushroom Phorid Flies are extremely specialized, only capable of feeding on actively growing mushroom mycelia. Larvae cannot develop on dead/steamed mycelia. Spawn Run is ~16 days on mushroom farms.
Mushroom Phorid Larva
2 week old sciarid larva
3 week old sciarid larvae
Mushroom Phorid Larva
Phorid Pupa 1
Phorid Pupa 2
Case Hold Compost
Phorid Pupa 1
Pupation
Larvae develop and pupate in the compost. As the compost matures a casing layer is applied on top of the compost. The casing layer has antimicrobial properties, adds and retains moisture, and helps to stimulate pinning (growth of the mushroom fruiting body). The Case Hold phase lasts ~14 days on mushroom farms.
Adult Emergence
Adults emerge 20-28 days after eggs were laid (based on growing conditions) typically when the rooms are being harvested. Because adults live for ~5 days, they must very quickly find a mate and lay eggs. Flies emerge in harvesting rooms and leave these rooms to find a mate.
Mushrooms are picked in three successive harvests. Mushroom flies vector mushroom diseases that can devistate yields and lead to a complete loss of the third harvest.
Mushroom Phorid Fly Adult
Sciarid Adult
disease infested 3rd flush
Mushroom Phorid Fly Adult
Mating
Flies leave the harvest rooms and mate outside. Flies are most active at dawn and dusk, but mating can happen any time. After mating, a female will locate a spawn run or case hold room to begin the process continue a cycle. The fly life cycle is 21-28 days, and one female can lay 50 eggs, so it does not take long for populations to grow out of control.
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While outside, phorid flies may be blown by the wind into residential communities, with potentially thousands of flies invading a single home in a given day. Because flies typically only live 4-5 days, homes experiencing strong invasions are likely getting new flies every day.
Flies on a vent window
Worker creating an attract and kill station
Flies on a vent window