I noticed something on the wall adjacent to the stairwell leading up to my apartment on one September evening: An unidentified bug just standing there, doing nothing in particular.
I assumed that the big was just resting. I left it be. However, I happened to notice the next day, and the day after, that the bug was still standing in the exact same spot. It was so still I wondered whether it was dead, but upon close inspection I could see that its antennae were moving and its legs occasionally twitched.
I took the above photograph about three days after first seeing the bug. By this point I told myself that I would “rescue” it since I was beginning to think that some combination of being indoors, the color of the wall, and or the lighting had disoriented our six-legged friend. However, I forgot about rescuing the bug for another two days or so until I was walking out one evening. I noticed that the bug was still there and that its antennae were still moving. At this rate, I figured the thing could not be far off from dropping dead from starvation or something, so I decided it was then or never.
It was time to be a hero.
I returned to my apartment and retrieved about three ply of toilet paper. Then I went to the wall and used the toilet paper to gently pull the bug from the wall, maintaining just enough grip to keep it from going anywhere but hopefully not so much as to squeeze it into a grim demise. I took the bug downstairs and exited the building. Then, I released my light pressure on the tissue and the bug, which had stood in the exact same spot on a wall, almost un-flinching, for close to an entire week, immediately flew away. While it did not stop to say thank you, I like to think that it was thanking me from the bottom of its little bug heart.
As I explained nearly four years ago, one of the most important parts of being a hero is telling everyone that you did something heroic. With that task accomplished, I decided to investigate what the bug was. Perhaps I should have done that before returning it to nature – but that ship had sailed (or flown the coop). I had a decent photo of the bug (see my photo near the top of the article), so I sent the photo to Google to see what Google came up with.
Google returned a good number of images that almost exactly matched my bug – so all that was left to do was to get the name. All the sources were in accord: I had rescued an Ailanthus Webworm Moth. See BugGuide (to-the-point sitename) for a good collection of photos.
Knowing what it is is not the same as knowing about it. To learn more, let us turn to pages about it at WhatsThatBug.com and Moth Identification.
WhatsThatBug tells us that the bugs technical name is the Atteva aurea, and Ailanthus Webworm Moth is an alternative name. My photo shows it at rest – and the article notes that it “often holds its wings tight against its body when not in flight.” Its tightly-held wings are colorful, as you can see in my photo, and have “a wingspan of around 1/2 inch.” While I did not photograph it in flight and only saw it flying for about a second, that sounds about right. Moth Identification opined that “[t]hese colorful moths look like a beetle or bug when not flying and a wasp in flight.” To be sure, I had not realized it was a moth when it was at rest.
WhatsThatBug explains that our moth had already gone through four life stages (unsurprising as it is a moth): Egg, Caterpillar, Pupa, and then Adult Moth. Adult moths emerge in the summer, so we can infer that it had popped out of its pupa not too long before it found itself lost in my building (Moth Identification lists its season as June-August). Moth Identification noted a moth fact that made me feel even better about my small act of heroism: Adult moths have a “long lifespan.” Apparently, I did not save the moth equivalent of a cicada, but instead a little bug that may have a long (very relative), happy (so long as it stays outdoors) life ahead of it. Well – not too long in New York City: The Missouri Department of Conservation reports that notwithstanding their “very long life-span,” they “cannot survive cold winters, so when it freezes, northern populations are wiped out.” I suppose it may have a few months ahead of it, at least. Also according to Moth Identification, “[t]he female lays eggs within the webs mostly during the evening that overwinter and finally hatch by late spring.”
The common name of the moth betrays its primary food source. Quoting WhatsThatBug:
The Ailanthus Webworm Moth is primarily associated with the Tree of Heaven, an invasive species from China. This moth also feeds on other trees such as the Paradise Tree (Simarouba glauca), and Simarouba amara.
WhatsThatBug notes that it is “native to tropical areas,” including Costa Rica and Southern Florida as examples. New York City is definitely not a tropical area. Why was it here? Quoting WhatsThatBug: “[I]t has expanded its range in response to the spread of its primary host, the Tree of Heaven.” But how has the Tree of Heaven spread? “Urban areas and nurseries with Ailanthus trees are hotspots for Ailanthus Webworm Moth populations.”
WhatsThatBug indicates that while our friend is not native to New York City, it is not especially harmful. In fact, the site suggests that the moth may help control the spread of the Tree of Heaven, with the caveat that it may also inadvertently spread it. However, in good news, the moth has a “[l]imited impact on tree populations” generally. Moreover, “[t]he Ailanthus Webworm Moth also plays a key role in polinization” and is “[a]ttracted to pale or white flowers with flagrance.” The Missouri Department of Conservation did caution that while the moth can hardly be called a “pest” since its primary food source is an invasive species, “in regions where other host plants grow, such as avocado, this species may be a pest on them.” I have not seen many avocado trees in Brooklyn – so perhaps it is all good here.
All-in-all, it seems like my good deed may be a small net positive for nature in Brooklyn. But there is one un-solved mystery. Why did this moth, which according to WhatsThatBug is “active during the day and night,” stand still on a wall, completely inactive for slight antennae twitch, for nearly one entire week (it may have been more thana week – it is possible it was there for a couple of days before I noticed it). I occasionally get moths in my apartment and they tend to fly around randomly. Yet this moth was apparently going to stand horizontally on that wall until life left it. Unfortunately, none of our sources answer this question. I suspect that my original theory that it became disoriented indoors – both for being indoors and also because of the color of the wall and the lighting – caused it to become sedentary. Fortunately, it was hardy enough to hang in there until a humble hero (cough, cough) came to the rescue.
I leave you with a video of the moth on goldenrod courtesy of Bug News so you can see it in action (something I was barely able to do myself). I wish my rescuee the best of luck this autumn (come to think of it, would it have preferred to be indoors for the winter?).
