Life Span of a Grasshopper

Q: What is the average life span of a grasshopper?
Chessnie

A: "Hmmm...this actually is tougher than you'd think," muses Jeffery A. Lockwood, entomologist professor at the University of Wyoming.

Aging and natural lifespan generate much interest among researchers these days but information is scarce. Lockwood hazards an estimate: about a year.

Females lay eggs in mid to late summer. The eggs spend the autumn and winter dormant in the soil, about ten months. A typical grasshopper hatches, goes through five molts (called nymphal instars), and becomes an adult after the fifth molt. Each of the nymphal stages lasts five to ten days, depending on temperature. So a grasshopper takes about 25 to 50 days to become an adult after hatching. Counting in life as an egg, the grasshopper is about 11 months old when she reaches adulthood.

Now, the tricky part: life as an adult. She takes ten to 14 days to reach sexual maturity and mate. She lays an egg pod every week or so until she lays one to three pods. Then she dies. So she lives about 30 days as an adult. Adding in time as an egg and spent in nymphal stages we get a 12-month life span.

Of course, a bird or other predator could eat her before then. Grasshopper mortality rates indicate she has a 50 % probability of dying within 50 days after she hatches. This says nothing about the chances some parasite will lay eggs inside the original grasshopper egg, killing her before she hatches.

Further Reading:

U of Wyoming: Grasshoppers of the west

U of California, Berkley: Crickets and grasshoppers

(Answered Oct. 11, 2002; updated Dec. 4, 2007)