The adult SWD is about 2 to 3 millimeters long, with distinctive red eyes and a yellowish-brown body. The males have a characteristic dark spot on each wing, which gives the species its name.
SWD females possess a serrated ovipositor, an adaptation that allows them to cut through the skin of ripening fruit to lay their eggs, making them particularly troublesome for fruit producers.
How Salt Water Makes theLarvae Wiggle Out
Soaking strawberries in salt water is a method that exploits the larvae’s sensitivity to changes in their environment. When strawberries are submerged in a salt water solution, typically made with a ratio of about 1 tablespoon of salt per cup of water, the osmotic pressure changes around the larvae.
Measuring salt beside a bowl of strawberries and water
Measuring salt beside a bowl of strawberries and water
The salt water draws water out of the larvae’s bodies, causing them to become distressed and vacate the fruit insearch of a more suitable environment. This reaction is what causes the larvae to wriggle out of the strawberries, making them visible to the naked eye.
