Saturday, August 05, 2006

Cicadas and Cicada Killers

Cicada-killer Wasp [wings open]

Cicada-killer Wasp [wings closed]
Photos by Lloyd Spitalnik [
taken at Sterling Forest - 8/1/06

This year's first annual or dog-day cicadas showed up in Central Park about two and a half weeks ago. Jimmy Lewis, one of the regular Moth devotees, heard a single Cicada song on the afternoon of July 19. About a week later we began to see cicadas emerging from their larval cases on the usual trees near Cedar Hill, at the path to Fifth Avenue and 79th Street. [See post of 7/31/06]

If the cicadas are here, can the cicada-killers be far beyond? One follows the other, as the night the day. [That may have a familiar sound, but Shelley and Shakespeare's copyrights expired a few years ago.]

Three nights ago Nick, Noreen, Lee, Jimmy and I made our way to the usual Cedar Hill spot, near a small outcropping where we've watched cicada-killer wasps digging their tunnels in years past. Sure enough, we saw the tell-tale little mounds of damp earth near the rocks, with small tunnel-like holes at the end of each mound. Within a minute or two, out came a cicada-killer, the largesat wasp in North America. She [only the female makes and provisions the nest] was backing out of the tunnel, adding another little pile of earth to the mound. Then back she went to dig some more.

Below, some internet information about cicadas and some rather gruesomefacts about cicada-killer wasps.


from Wikipedia]

Most of the North American species of cicada are in the genus Tibicen—the annual or dog-day cicadas (named after the "Dog Days" because they emerge in late July and August). [Our Central Park cicadas are annualacicadas.]

Adult cicadas, sometimes called imagines, are usually between 2 and 5 cm (1 to 2 inches) long. Cicadas have prominent eyes set wide apart on the sides of the head, short antennae protruding between or in front of the eyes, and membranous front wings. Desert cicadas are also one of the few insects known to cool themselves by sweating, while many other cicadas can raise their body temperatures voluntarily to around 40°C, even when the air temperature is only 18°C.

Male cicadas (and only males) have loud noisemakers called "tymbals" on the sides of the abdominal base. Their "singing" is not stridulation as in many other familiar sound-producing insects like crickets (where two structures are rubbed against one another): the tymbals are regions of the exoskeleton that are modified to form a complex membrane with thin, membranous portions and thickened "ribs". They rapidly vibrate these membranes with strong muscles, and enlarged chambers derived from the tracheae make their body serve as a resonance chamber, greatly amplifying the sound. Some cicadas produce sounds louder than 106 dB (SPL), among the loudest of all insect-produced sounds. (This amazing sound has frequently inspired haiku poets in Japan to write about them.) They modulate their noise by wiggling their abdomens toward and away from the tree that they are on.

Only males produce the cicadas' distinctive sound. Both sexes, however, have tympana, which are membranous structures used to detect sounds; thus, the cicadas' equivalent of ears.

Cicada killer Wasps

The cicada killer wasp, Specius speciosus is the largest wasp we have in the Eastern United States

Cicada killers, which range from 1" to 1.5" and have a wing span of nearly 3", are solitary digger wasps that do not make paper nests or hives like many of their relatives.

A female cicada killer constructs a nest in the ground consisting of long tunnels. Dry, sandy or slightly elevated soil is preferred because it does not invite mold or mildew.

The burrow has a gentle sloping entrance about six inches long then usually a right angle turn. The turn is probably for protection against other predators. The tunnel then continues another 6 to 8 inches and ends in one or several globular cells about 1.5" in diameter. Once the nest building is completed, the hunt begins.

Adult wasps emerge at the same time as when the cicada are most numerous. Often you can see the large cicada killer flying around a tree in which a cicada is singing. Suddenly the regular buzz of the cicada breaks into a distressed cry (similar to an electric shaver when you try to cut steel wool). The cicada, which has no defense except flight, is quickly overcome by the wasp's sting, and often both fall to the ground during the struggle. The sting does not usually kill the cicada, but paralyzes it and throws it into a comatose condition from which it never recovers.

Now the real work begins. The cicada, being larger and heavier than the wasp, cannot be flown away simply. It has to be laboriously dragged up a tree or other higher point. Frequently it takes the cicada killer an hour or two to get high enough to fly and glide at a downward angle toward its nest.

At long distances from the burrow, several climbs have to be made and the return trip may take the better part of the day. After reaching the burrow, the cicada is dragged down into one of the cells and a single egg is deposited near the base of the cicada's middle leg.

The egg hatches in 2 to 3 days and the larva immediately starts to feed on the paralyzed victim. If the cicada dies, the venom of the wasp's sting helps to preserve the tissues for the feeding larva. The larva feed from the outside until full-sized in about a week or so. Only the hollow shell of the cicada is left over. Often two cicadas are placed in one cell with on egg. This results in a larger adult wasp. It is believed that wasps resulting from one cicada turn into males, while those resulting from two cicadas turn into females. Females are always much larger than male.

After the larva reaches its maximum size obtainable from the food supply at hand, it spins a silken cocoon which is completed in two days. This "silken" cocoon is a mixture of earth and silk, and has special breathing holes around the middle. The larva remains unchanged and stays in this "resting" stage throughout the winter.

In the spring, the larva changes into the transitional pupa, shortly before the appearance of the adult. The newly emerged adult chews its way out of the cocoon and digs its way to the surface and completes its one-year life cycle. Like all wasps, the cicada killer can sting as many times as it cares to. Being our largest wasp, the sting is severe, and needless to say, should be avoided.

Friday, August 04, 2006

The Mulberry--a last note

Betty Jo McDonald, a Pale Male fan from Camarillo, CA, who once sent a batch of unbelievably delicious avocados and limes from her own backyard trees for the delectation of the Central Park Hawkwatchers, wrote me a note today about the death of the Mulberry Tree:


I am not surprised that you wept on the news of the tree's death. I have done so many times over the unnecessary removal of a tree. They live so long, provide so much to our world--shade, beauty, fruit, nuts, shelter for animals; they even nourish their own roots by dropping leaves. Indeed, RIP to the old mulberry.

Betty Jo

I answered:

Thanks, Betty Jo, though this removal was not unnecessary. The old tree just keeled over.

Lee's tree with a PS from Regina

Nan Holmes, a frequent correspondent of this website, comments on Lee Stinchcombe's painting of the old mulberry tree , posted here yesterday. Thanks, Nan, from all of us.

"The tree is symbolic, of course, of the losses each of us have. Your connection, and indeed that of all the CP regulars, is profound to this park and its residents: flora; fauna; mammalian; raptor. In the midst of this city you all have an almost rural connection with this piece of land."

PS. Regina sends in an addendum this morning:
 We did a ring count and the tree was about 80-85 years old, which coincides  with our
records of when it was planted

Thursday, August 03, 2006

In Memoriam

A painting by Lee Stinchcombe of the beloved Mulberry tree
Today I received an e-mail letter from Regina Alvarez, Woodlands Manager of Central Park :
Hi Marie -
I thought you might like to know that our old friend, the Mulberry tree
in Shakespeare Garden finally fell over. Very sad day. We are removing
it today.

The letter made me weep. When I called Lee Stinchcombe with the news she wept too It's odd to feel so connected to a member of a different Kingdom from one's own, but that Mulberry was a beautiful old tree,and we all loved it. The Shakespeare Garden, a magical spot, will be less magical with the Mulberry gone.

RIP, old friend.

Lee sent me a photo of a painting she had done a few years ago of the tree. That's it above.

Tuesday, August 01, 2006

Mars Malarky

I am on a mailing list entitled Star Struck that emanates from the American Museum of Natural History's Hayden Planetarium. It sends out frequent updates on astronomical issues and events. Today a note went out to the Star Struck list from Neil deGrasse Tyson, head enchilada of the Planetarium, discussing a hoax I was familiar with. I had received three versions of it during the last few weeks, and maybe you have as well.:

1 August 2006

Dear Star Struck,

Nearly everyone I know has received an e-mail about Mars from an anonymous source, but sent to them by friends who could not resist forwarding the message to their entire address book. The e-mail declares that at the end of this month (August), the planet Mars will be closer to Earth than it has in the past 60,000 years, thereby offering spectacular views of the Red Planet. The commentary proclaims, with liberal use of exclamation marks, that Mars will appear as bright as (or as large as) the full Moon in the night sky.

This Martian hyperbole dates from August of three years ago, when the message was mildly factual, but vastly over-stated, leading people to believe Mars would be so bright that you might need sunglasses at night while driving. The rapid spread of this information was like some sort of brain info-virus, and led to at least one daily newspaper comic that showed Mars crashing into a home while the husband and wife were indoors, debating how close the planet will come.

Every 26 months, or so, Earth makes a close approach to Mars, as our smaller, swifter orbit "overtakes" Mars around the Sun. Because both the orbits of Mars and Earth are mildly elliptical, some close approaches between the two planets are closer than others, but by barely perceptible amounts.

So the proximity of Mars to Earth three years ago, while indeed closer than in the past 60,000 years, was nonetheless no more meaningful than me swimming a hundred yards out from the California coast (instead of my usual seventy yards) and then declaring to the world "I have never been this close to China before."

True, during close approaches, Mars slowly becomes one of the brightest objects in the night sky. But how bright? Slightly brighter than Jupiter's' average brightness. And not as bright as that of Venus. Yet nobody has ever issued warning statements about the visibility of Jupiter or Venus. In any case, Mars has had a "close approach" 3,000 times in recorded history, and, of course, billions of times in Earth's history.

Now it's time for you to send this antidote to ail the infected people in your address book.

As always, keep looking up.

-Neil deGrasse Tyson

Department of Astrophysics
& Director, Hayden Planetarium
American Museum of Natural History

To add your name to the Hayden Planetarium's
star-struck e-list, send a blank e-mail to

Monday, July 31, 2006

Much ado about Mothing

FLASH: Last night , July 31, the first of the Underwing moths with solid black hindwings appeared at the Moth Tree: the Yellow- Grey Underwing. Also three [count 'em, 3] Oldwife Underwings. Photos of these two not available yet.

Meanwhile, here's a sampling of some of the visitors to the Moth Tree at the East Drive between Pilgrim Hill and the Boathouse and to a tree just west of the 79th Street entrance, near Cedar Hill during the last weeks of July:
Ilia Underwing -- [Catocala ilia ] the most common Underwing moth at the Moth Tree--very variable in forewing pattern---and American Idia [ Idia americalis]

A partially opened Ilia, revealing the bright orange and black hindwing pattern.

Ilia Underwing -, slightly open

The Ex-Girlfriend [Catocala lineela]

We call this moth the Ex-girlfriend because it appears as The Girlfriend [Catocala amica] in the one and only field guide, Eastern Moths by Charles V. Covell. In a list of corrections in a new edition of his book, Covell recanted, and changed the ID. He renamed this one the Little-lined Underwing . But we prefer to call it the Ex-Girlfriend, since that's what indeed it is. It is one of the early underwings to come to the Moth Tree, arriving in late July along with the Ilia, the Ultronia, and the Oldwife.

Firefly -- probably Photinus pyralis

Ultronia Underwing -- Catocala ultronia

At 79th St. -- Cicada just emerged from its pupal case [above it] on a Beech.

At 79th street, an egg mass deposited by a Gypsy Moth on the same tree.

Witnesses to all the above wonders, and more: Nick Wagerik, Lee Stinchcombe, Noreen O'Rourke, Jim Lewis and me--the regular Central Park Mothers [rhymes with authors]. Many other occasional visitors too numerous to mention here.

Sunday, July 30, 2006

Fodder for Pale Male?

In regard to the news of a chipmunk in Central Park, frequent correspondent Bill Trankle of Indianapolis wrote:


It seems Central Park is certainly not static; quite amazing considering it is completely surrounded by dense urban infrastructure. To that point, you mentioned in your squib that chipmunks are found in many other NYC parks, and I was curious if you knew what the distance is from Central Park to the nearest park where chipmunks are common. Even a distance of a few blocks would be an amazing migration for a tiny rodent that would be completely exposed during most of the trip, and if it's a distance much greater than that it becomes unfathomable. It raises all sorts of questions like why did it leave its original environs in the first place--it's not like there's a chipmunk version of Mapquest where they could see, "Hey, 10 blocks southeast of us is the promised land." It reminds me of the ancient Polynesians leaving their homes to travel thousands of miles of ocean to a speck of land that they somehow "knew" was there. Anyway, best of luck--a healthy chipmunk population would give PM and his progeny yet another diurnal food source, if they're quick enough to get 'em!

I answered:

I agree. That's why I firmly believe that neither of these handsome critters got to the park under its own steam. Dumped pets, I'd say.

The thriving threesome

photo by Lincoln Karim

Green Heron news from the Upper Lobe

Remember the former fuzzy foursome? Only three of the young green herons are left; the smallest of the brood died last week, almost certainly of starvation. It isn't because there wasn't enough food. It's because he was too small and got lost in the shuffle while his bigger siblings got all the food. Two of the surviving chicks have become branchers-- that is, they're venturing out of the nest onto nearby branches, practicing flight techniques in relative safety. . One remains in the nest , at least when last seen .

Many young birds in tree nests become branchers in preparation for fledging. How did the Fifth Ave nestlings from 1995 to 2004 manage this stage when born in a nest far from any tree? Similarly, what about the Trump Park kids on a sheer wall thirty-five stories from street level? They used adjacent balconies, ledges, fire escapes and rooftops as their branches, hopping from one to another in preparation for longer flight.