Monday, July 4, 2011

Brood XIX—the famous 13-year “Great Southern Brood” Magicicada emergence!

Yes, yes, it’s a mushroom blog, but I keep finding other marvels too, and I take pictures and then I have to post about it.  And sometimes it’s just in-between mushrooms.

I’ll stall a little to give you a chance to leave, if you’re not into big close-ups of bug faces and bulging red eyes (especially the very last image) and waving bug legs, and worse, because that’s what’s coming up here. I even heard some “Bleah” and “Ew” from people who aren’t all that squeamish and “love nature.” I got a little squirmy about some of this too. But I did it anyway, even after telling myself not to get all swept up in this crazy Magicicada phenomenon because half the internet was going to be filled with images of emerging cicadas, so why should I make pictures of the same thing? But I couldn’t resist, once I saw it.
It was nuts!

(Last chance—leave now if you’re not into giant bug faces)

So, let us begin.

Mid-Missouri (and many other states) just experienced the emergence of millions of 13-year cicadas. There’s “annual” cicadas and “periodical” cicadas, and the broods are made of periodical cicadas, and Brood XIX is Magicicada with a 13-year life-cycle (there’s four in the genus, I don’t know which one we had, could be more than one).

Periodical cicadas have 13- or 17-year lifecycles. The "annual" ones actually have 2-to-7 year cycles, depending on the species (there’s not really a one-year model) but some come out every year. They’re not synchronized, so even though a species may have a 3-year cycle, some come out one year, and another group comes out the next, kind of leap-frogging. The "years" refer to time spent underground as larvae, quietly feeding on sap from tree roots. Broods are named for life-cycle length, and region, and the fact that they’re periodical, and synchronized so they all come out the same year. Brood XIX only comes out every 13 years, and in a particular area. It’s also the biggest brood (numbers-wise), showing up along the east coast to the Midwest, in about 15 states! All at once! Pretty much! Depending on weather and soil temp. I can’t tell you how long it took me to get this straight. I hope I have it right.

I’ve never caught the familiar dog-day cicada molting (well, once, but years ago, and no camera), but there were so many of these (let me stress that—SO MANY) that it was hard to miss. For at least a week, you could just walk outside and see them all over the trees and walls and fences around the house, before they took to the trees and started singing and looking for mates. Pretty much everywhere. I took pictures over several weeks, so some are on fences, and some are on trees, and some are in state parks and some are in my front yard, etc.

Here we go!

Cicada-4         DSC09545 

Cicadas busting out of their shells (things that make you go “bleah”)

cicada bulge

Their best option is to be vertical. After they split their shell (“eclose” from their “exuvium”) they stick out horizontally for a while, with the end/tip of their abdomen still in the shell.


(From above--the camera’s aimed towards the ground)


I like their little orange armpits.

Nobody talks about how their tiny empty feet stay grabbed onto things.

cicada face top view

Above, that’s one of my favorites…

cicada emerging top view

They just hang there for a couple hours, doing whatever secret things they do. Their wings start to un-crumple.

What happens next is they wiggle all the way out of their shell and grab onto it (or a tree or whatever) and hang vertically, as their very delicate wings take shape and dry. If they’re not in the right position when they come out of their shells, things don’t go right. Sometimes they can’t get into the right position, sometimes because there’s so many other cicadas in the way, but their sheer numbers (hundreds of thousands per acre) compensate for the ones that don’t make it. I skipped pictures of problems. Big fat “ew” there.

There’s billions total in this brood, no lie.


They start out pink and tender (just like soft-shelled crabs!) with tomato-red eyes and two dark patches.

cicada hanging on shell side view

cicada hanging

Cicada wings flat
I wonder if they saw me looming over them in their most vulnerable state and thought, “Oh sh*t oh sh*t oh sh*t”…sorry!

Here’s one (below) in an in-between stage, starting to darken…
halfdry cicada

brood 19 cicadas on bush                             

  brood 19 many on bush

Above left, dozens of cicadas and shells on bushes in the backyard      
Above right, hundreds on bushes at the edge of the woods

Here’s five of them marching along a blooming rose bush, really lush colors all around, fresh cicadas, after a spring morning rain
brood 19 5 cicadas on rose bush

Let’s see what else we have here--

Fresh cicadas

Mating cicadas!
mating cicadas on ground2

They lay their eggs in slender branches, near the end, by cutting a series of slits in them, and laying a bunch of eggs in each slit. I didn’t catch them laying eggs, but I did find all kinds of evidence of this. First I saw crazy numbers of branch tips all over the place, which I thought was just an odd result of some recent violent storms. They were everywhere, for weeks. These branch tips had a lot of people scratching their heads! Eventually I understood that the branch ends must have been weakened by the slit-making, making it easy for storms or wind to tear them off the tree.

cicada flagged branches

cicada flagged branch
Above, a torn-off branch. If you click to enlarge you can see many slits along the broken end.

Below, cicada egg-laying slits.
 cicada egglaying slits

Here’s one with my finger for scale:
Cicada egg-laying slit with finger for scale

Then I got even more curious, and started messing with the branches, and broke one open, and there were the eggs (sorry)!
cicada eggs

They look like little grains of rice. They lay 24-28 eggs per slit.

Shortly, the eggs will hatch, the nymphs will burrow into the ground (oh, how I wish I could have found some newly-hatched nymphs!), and spend 13 years underground, sucking sap from roots and not doing much of anything else, as far as I can tell. Occasionally molting as they get bigger. That’s really all.

So, over about six weeks, mid-May to the end of June, this whole 13-year cicada thing happened.

Bonus: I noticed that shiny black cars with their brake lights on looked like Magicicadas!

The red light of their eyes goes out when they die:
dead cicada

And this, below, turned out to be my all-time favorite image capture of the whole crazy phenomenon:

cicada head and ants

I owe a lot to these websites that helped me untangle the facts:
What's that bug?                                                                              
Cicada Mania                                                                            

The end!