Did you know that you can tell the temperature by listening to the crickets and katydids chirping at night?

In 1897, A tufts professor named A.E. Dolbear published a paper showing that the rate of chirping of crickets and katydids varies with changes in temperature. His math equations for this phenomena became known as Dolbears law. Interestingly enough, it is thought he derived much of his data from a woman named Margarette W. Brooks who in 1881 published a report titled,  “Influence of temperature on the chirp of the cricket” in Popular Science Monthly.

Board member and volunteer gardener Mary Anne Spradlin, brought in a Fork tailed Bush Katydid for ID this week and it got me thinking about how the night time temperatures are dropping and while there is perhaps a bit more urgency in the crickets and Katydids chirps with the advancing of the season, the rate at which they are chirping is certainly slowing down in the evenings.

In case you are laying awake at night and want to factor in the temperature by counting the chirps outside your bedroom window, here is the equation:

T = 60+[(N-19)/3]

N being the number of chirps in a minute

T being the temperature




Scudderia furcata, Fork Tailed Bush Katydid, found in the Gaiety Neighborhood.