Tennessee Wastewater Operator Practice Exam

What condition do filter flies require for their egg laying and reproduction?

1. Moist surfaces

2. Dry surfaces

3. Submerged areas

4. Sunlit areas

The correct answer is: Dry surfaces

Filter flies, also known as Sciaridae or moth flies, require moist surfaces for their egg laying and reproduction. These flies are commonly found in environments where organic matter is decomposing, such as in wet, decaying materials found in wastewater treatment plants or near stagnant water areas. The moisture is essential because the larvae, which hatch from the eggs, thrive in these damp environments, feeding on decaying organic matter. Without the necessary moisture, the eggs may not develop properly, or the larvae could struggle to survive after hatching. Therefore, the necessity of wet conditions is key to their life cycle. The presence of dry surfaces or areas submerged under water does not provide the suitable habitat that filter flies need for reproduction, nor does exposure to direct sunlight contribute positively to their reproductive success. This ability to thrive in moist environments is what allows them to become a common nuisance in places where wastewater and organic waste are present.