Cicada Mania

Yesterday I visited my family’s house in Metuchen, New Jersey. I looked in the backyard and found loads of cicada holes — a hole every 6″ to 12″. I was also clear that animals, like squirrels and raccoons, had been digging at many of the holes. Today I got a spade and gently dug around one of the holes. About 3″ down I found a Magicicada cassini nymph, about 1 inch in length, legs wiggling slowly, red eyes.

Here’s the hole:

Here is the nymph:

It’s clear that the cicadas are ready to emerge, and are just waiting for the temperatures to get a little warmer (to warm their bodies to around 64 degrees F). Today reached 72 degrees F. It will reach 77 F on Friday, and some will likely emerge. Saturday temperatures will be back down to 39 F. These cicadas will likely be confused for a little while.

More holes, many of which were widened by predators looking for a cicada snack!

Also visit: updates on the emergence.

I noticed that the radiolab Cicada Tracker folks are showing that soil temperatures throughout the emergence area hit 64 degrees this week, but few if any cicadas emerged from the ground. Why not? My guess is that the soil was not warm enough for a long enough time to warm the bodies of the cicadas to 64.5 degrees F. They might have warmed up for a few minutes, started heading toward the surface, but then cooled off again and stopped their ascent.

It’s a good thing that cicadas did not emerge this week. They would have arrived to trees with few leaves (which offer a little camouflage), cool weather and lots of rain.

I hope that the radiolab Cicada Tracker folks are continually sampling temperature information, so we can get a clear picture of not only the temperature that causes them to emerge, but how long it takes to transfer the warmth of the soil to the bodies of the cicadas.

If you’re interested in the topic, a great paper to read is Thermal Synchronization of Emergence in Periodical “17-year” Cicadas (Homoptera, Cicadidae, Magicicada) by James Edward Heath, American Midland Naturalist, Vol. 80, No. 2. (Oct., 1968), pp. 440-448.

Here is a quote:

Soil temperature at 20-cm [7.87 in] depth in seven locations averaged 17.89 C [64.202 F] at the time of emergence, regardless of date. Cicadas emerging from burrows had average body temperatures of 18.04 C [64.472 F]. Synchrony in emergence may be due to animals reaching a critical threshold temperature.

There is also a minimum temperature cicadas need to be able to fly and sing, and a temperature at which they get too hot and seek shade. Read more about that.

My Goals and Objectives for the Brood II Emergence:

1. Continue to spread the word about Brood II periodical cicadas.
2. Take excellent photographs of all three 17-year Magicicada species: M. septendecim, M. cassini, and M. septendecula.
3. Record the songs of each of the species.
4. Document the emergence on video from start to finish.
5. Visit some of the events and exhibits at the Staten Island Museum.
6. Eat at Chez Catherine a cicada-themed restaurant in Westfield,NJ (Westfield will experience Brood II BTW).
7. Travel all around the NJ area, report cicada signings to Magicicada.org.
8. Look out for rare white or blue eyed cicadas.
9. Meet up with fellow cicada enthusiasts and researchers like Elias Bonaros and Roy Troutman.
10. And of course dress the part, and wear cicada-related clothes and paraphernalia.
11. Make sure my sister’s chihuahua doesn’t choke on a cicada.

Chances are you might see me during the emergence. I’m told I look like “Lucius Malfoy”.