Tiger Swallowtails of NY: Finger Lakes, Part II

[Chuck]

About Papilio canadensis:

No source I've seen has ever claimed or proposed that canadensis is bivoltine; in fact most research, including extensive breeding experiments, indicate canadensis is an obligate dipauser and univoltine.

The wonders of iNaturalist images by nature lovers are well used to reveal the flight period of canadensis in Alberta. Here one can see a number of adults photographed during the month of August, over several years. https://www.inaturalist.org/observation ... fiable=any

UNLESS the iNat records above are wrong; according to iNat, Papilio rutulus also occurs in Alberta. https://www.inaturalist.org/observation ... fiable=any

Now, the horrible fault of iNaturalist! Same search but for New York state (ie canadensis, August, New York) has 23 observations ALL OF WHICH ARE WRONG.

In general, Papilio canadensis does not occur in Finger Lakes region, whether the geological Finger Lakes or the state-dictated marketing Finger Lakes region.



To the north (top) of regions 1, 2, 4, and the west (left) of region 5 is Lake Ontario, and above that, Canada.

In Canada, pretty much everything due north of the NY lake shore is Papilio canadensis; Toronto is a tad NW of the most NW point of NY (top of region 1) and Toronto has glaucus/ MST, but not too far north of Toronto it's canadensis. The previously cited articles have maps of canadensis, glaucus, and MST distribution.

In NY, canadensis range follows, perhaps not surprisingly, that of many other species, such as Eacles imperialis pini. P canadensis is found in the cold hills of regions 5 and 6, with limited range along the northern NY lakeshore of region 4, and rarely region 2. Region 2 being Finger Lakes (according to the marketing experts in New York State government) technically then, Papilio canadensis does occur. However, I've not been able to prove the existence of canadensis anywhere in Finger Lakes south of the lake shore.

[Chuck]

Now, on the bigger scope of the Tigers in Canada and Finger Lakes:

Morphology, food plants, and flight period are used to determine the species. In Toronto it's either glaucus or MST; on the eastern end of the lake it's either canadensis or MST. I'm dubious of the validity of some of the morphology, but the flight periods have limited overlap.

In Ithaca (bottom of yellow region 4) Hagen and Lederhouse (1985) also show distinct flight periods for glaucus and MST ("late flight").

Where most of my field work has been done recently (just to the right of the number 2), it's a train wreck. This year there was no observable wane in any population's flights, only an increase from mid-May, with big increases first weeks of July then again August, with a final drop off mid-August. As noted, I'm now dubious of morphological identification based on what I've seen, and without (at least this year) any drop in population there is no way to say "this is spring form glaucus, this is MST, this is summer form glaucus."

There are hints, albeit the ranges are in flux, likely due to warming. Hagen and Lederhouse (again, 1985) said there (was then) no second generation of glaucus in Ithaca or in NY above 41 degrees (most of my field work is above 42.6 degrees.) This is reflected in where I started this whole study, first post on the subject on the old forum: in the 1970s and 1980s Finger Lakes also had only a June flight of Tigers, but now we have a flight(s) in massive quantity in July and August.

I propose that there still is no second generation of glaucus, despite it being plainly evident that the spring form glaucus in June has more than ample time to produce a second generation. In fact, warming aside, there always has been sufficient time, at least for the past 7,000 years. So I'm proposing that in our area there is no "summer form" glaucus, which would need breeding experiments to prove.

I'll wrap up for now with a heretical proposal that will leave me open to ridicule: From various sources and examining the range of many species, there is what I think of as The Sudden Stop Line of Death, from Erie down to about Pittsburgh, across to north of Philly, then up inshore of the Atlantic coast. Above that line, many southern species are rare, or don't exist. For example, Battus philenor and the black female form of Papilio glaucus. But there are many, many others. I propose that black glaucus doesn't stop at that line because of the lack of a mimic, but because the species (used loosely) ends there, meaning that in Finger Lakes the two flights (not counting canadensis) are not glaucus, but something else. Whether they be a valid full species as we know it now, or subspecies, or cryptics or recombinant hybrids, the two flights do not appear to be the same, and are markedly different morphologically from standard/ southern glaucus.

[jhyatt]

Very interesting, Chuck. Dogged, persistent systematic collecting can yield a lot of insights given enough time and material.

I'm wondering, does Collias eurytheme fizzle out above your "Sudden Stop" line?

Cheers,
jh

[Chuck]

Very interesting, Chuck. Dogged, persistent systematic collecting can yield a lot of insights given enough time and material.

I'm wondering, does Collias eurytheme fizzle out above your "Sudden Stop" line?

Cheers,
jh

Colias eurytheme is common in Finger Lakes. However, it flies very late here- small in numbers in late July, with about third week of August being the height of the population. When we have an unusually warm fall is when they fly into October (when everything else is dead) and that's when we get the really expressive forms- white females, very bright males, and expressive markings. We also have philodice, which flies from late May through the end of the season, and occurs with eurytheme.

I dabbled in Tigers in 2020, more doggedly in 2021, and hard core in 2022; in 2022 almost to the exclusion of everything else. I now have more questions than answers, and more questions than I started with.

One thing I noticed was the selection of nectaring preference, it changes every couple weeks. One could be looking for Tigers and see none, while there are dozens 500m away. The inference is that absence of observation is not evidence of absence. In NY: Ontario Co., Sodus Point the MST nectared on milkweed only a little bit (whereas other places the milkweed was covered with them) and only for a couple days. During the 8 or so days at the height of the flight they were readily observed flying all over, but damned if I could find them nectaring on anything. Then they disappeared, or apparently disappeared, with zero observed after about 15 July. But why? I saw Tigers three miles, and 12 miles, to the east. And 40 miles south Tigers were still out yesterday. So did the Sodus Point population uniquely crash? Did it move to an unknown nectaring source? Is the Sodus Point Tiger population MST which crashes, and so do the MST 40 miles south, but the 40 mile south population in late July/August yet something different?

Meanwhile, one field of thistle, popular with Tigers every year, I saw zero in 2022. ZERO. Why?

I have a pile of them for the geneticists, let them figure out what these things are, and are not. Whatever they discover, what is certain is that the behaviors (including emergences) vary drastically year to year, and by location.

[Chuck]

Very interesting, Chuck. Dogged, persistent systematic collecting can yield a lot of insights given enough time and material.

I'm wondering, does Collias eurytheme fizzle out above your "Sudden Stop" line?

Cheers,
jh

Oh, BTW John, on naming conventions: I referred to it as the Sudden Stop Line of Death, but I also think of it as the Terminus of Southern Aggression, a nod to the sudden termination of the aggressive ranges of many southern species. Do you have a preference?

[jhyatt]

Very interesting, Chuck. Dogged, persistent systematic collecting can yield a lot of insights given enough time and material.

I'm wondering, does Collias eurytheme fizzle out above your "Sudden Stop" line?

Cheers,
jh

Oh, BTW John, on naming conventions: I referred to it as the Sudden Stop Line of Death, but I also think of it as the Terminus of Southern Aggression, a nod to the sudden termination of the aggressive ranges of many southern species. Do you have a preference?

No real preference, Chuck - but now that I think about it, maybe one could designate the invasion of southern climes by northern species over the last century (P. virginiensis, B. bellona toddi, Coenonympha tullia, etc) as the "War of Northern Aggression". But that term may have already been pre-empted.

Down here near the VA/TN border P. glaucus is still flying, but is decidely scarcer than it was about 3 weeks ago. And like yours, our late season
(October) C. eurytheme are the biggest and prettiest of the year.

Our third brood E. marcellus are likewise the biggest and best-looking ones of the year, but by a huge margin they are the rarest. I've always wondered how such a scarce brood can lead to the exceedingly common spring brood of marcellus. Maybe some of the 1st or 2nd brood offspring don't eclose until the next spring?

jh

[adamcotton]

I've always wondered how such a scarce brood can lead to the exceedingly common spring brood of marcellus. Maybe some of the 1st or 2nd brood offspring don't eclose until the next spring?

Probably the majority of summer generation offspring do not emerge in late summer but go through the winter as pupae. I have often seen similar with local Leptocircini here, such as Graphium antiphates. Pupae from larvae I reared in late June often do not emerge until the following February. Of course, the offspring of the ones that do emerge in summer add to the numbers of the spring generation.

Adam.

[jhyatt]

I've always wondered how such a scarce brood can lead to the exceedingly common spring brood of marcellus. Maybe some of the 1st or 2nd brood offspring don't eclose until the next spring?

Probably the majority of summer generation offspring do not emerge in late summer but go through the winter as pupae. I have often seen similar with local Leptocircini here, such as Graphium antiphates. Pupae from larvae I reared in late June often do not emerge until the following February. Of course, the offspring of the ones that do emerge in summer add to the numbers of the spring generation.

Adam.

Adam,

Thanks for your comment. That would account for the higher numbers of spring-form specimens.

The three broods of marcellus are very recognizable - the spring form is small with short tails, the summer "brood" has much longer tails and is larger overall, and the rare fall ones are the biggest of all, very long-tailed and considerably darker. Are we therefore to assume that these differences are due to environmental conditions affecting pupal development? I guess it'd have to be that way, if the summer brood's offspring can become either spring or summer emergers... which begs the question of whether these are "broods" at all, in the usual sense of the term.
Cheers,
jh

[Chuck]

Tiny details in variations. I noted this one quickly, then looked at other specimens; the "window" within the black is there, but none have this level of brilliant blue. I wonder what is the purpose?

[Trehopr1]

I would think miniscule details or variations such as this bespeak of individual genetics at work. The bloodline (so to speak) within this particular butterflies ancestry produced this extra dash of blue.

I would hardly think there is a purpose to it or for it; it is simply an ever so slight (variation) which can occur in differing populations.

Just my humble opinion here. Perhaps, Adam would agree or could forward his own thoughts as he is our resident papillionid specialist.

[Chuck]

I would hardly think there is a purpose to it or for it; it is simply an ever so slight (variation) which can occur in differing populations.

I believe you are correct. It's a minor variation, albeit one that really pops out in real life, much better than in the photo.

I do wonder what morphological attributes are important, and which are not. Tails and eyespots I think are pretty well tested. There have been studies on black female glaucus and predation, as well as thermal effects. The fact that Tigers have three stripes, what if they had five? I read one paper (forgot which) that demonstrated that Tigers on flowers, with wings folded above the thorax, are shockingly difficult to see. I concur. It's the motion that gives them away.

[Chuck]

Some events are more fortuitous for some than others, and so it was 03 Sept 2022.

It's been over a week since I wrapped up the field work on Tigers. Admittedly, it was a relief. Kinda sad not to see another Finger Lakes MST though.

But alas, fortune smiled on me at a winery patio up on a hill. My family had already been seated while I grabbed drinks, and not noticed it. I of course have a habit of looking on the ground. And there it was.


It had been stepped on, specifically on the head, which was sad as there's no doubt it was headed to pupate- SO CLOSE! But lucky for me, otherwise it wouldn't have been there. Dead, black blood on the concrete. I of course picked it up and put it on the table for a photo, wouldn't you?



I sent the photo off to Eurytides who responded right away. And then I thought- duh, why toss it? So I went and hunted it up in the grass where I'd tossed it. I can't believe I found it. From there it went into one of those plastic bags they use to pack plastic forks and knives. Then overnight in the small freezer, followed by a rough passage to home port in 45kph winds and 2.5m seas. Then into the fridge at home.

To preserve it I first cleaned it with a Q Tip as much as possible, since there was black goo all over it. The still-inside goo had an exit near the head (from the death step) but not enough, so I slit the rear and squeezed the goo out with an a round punch. It too several runs over the body to get the goo out, and stringy stuff was torn out with a dental pick.

Then I used a plastic syringe (I love these things, I use them for all sorts of projects) to inject silicon, starting near the head and working backwards. And stuck a small triangle of cardboard into the rear for future pinning.





One hour later, the silicon stuffed body was able to be handled without squishing. There's discoloration, both external and internal.




I'm certain there's still biological goo in there which can rot, so tomorrow morning I'll hit it with some heat to dry it out.

[jhyatt]

Chuck,

Well done, but it sure sounds like a lot of work compared to freeze-drying larvae.

jh

[Chuck]

Chuck,

Well done, but it sure sounds like a lot of work compared to freeze-drying larvae.

jh

It really wasn't difficult at all. Snip end, squish out goo, fill with silicone. Last night I hit it with heat for 15 minutes to dry out biological goo remaining. Total time invested less than 30 minutes.

Freeze drying: some people have used 18 months in the freezer; I don't know what a commercial freeze dryer costs, I'm sure it's not inexpensive. A few years ago on the old forum I asked about vegetable dehydrators, but no response.

Far in the past I'd done some Lep larvae with the air pump and hair dryer method, which is slow and larvae tend to bend in a direction of their choosing. Silicone is faster, and one can shape the larva to be more natural.

I'll give it a week to finish drying, and post a photo.

[jhyatt]

I bet it turns out great, Chuck. Look forward to seeing the photo in due course. I've been spoiled on freeze-drying by working all my career in labs with easy access to high-vacuum pumps, liquid nitrogen, and vacuum chambers. I have no idea what a good dedicated unit would cost, but you're right, it'd be a lot.
jh

[Chuck]

Eight days after preparing the larva with silicone, there really isn't any change.

Depending on the lighting, it sometimes looks darker than it is; from some angles it looks translucent- and I note that some aspects changed from the "living" specimen, probably as a result of those organs/features being removed.




It was a poor specimen to start with, but it didn't get any worse.

Contrast the first image of the subject specimen with a live specimen from New Hampshire:



Given that the skin is relatively translucent, when guts are removed colors are lost. One could colorize the silicone somehow.

Aside from that, the specimen is pretty sturdy.

[Trehopr1]

I think the best way to appreciate lepidopteris larvae is through pictures (these days). With all the advancements in professional cameras, pixels, and even cell phone cameras -- there really is nothing that comes close.

I have seen a few select freeze dried larvae which turned out pretty dang good. However, the freeze drying apparatus is completely unaffordable for the private individual, thus, only those who have access to a lab environment could ever experiment with larvae.

There is of course an age-old time-honored method of "inflating" larvae which is (here and there) shown in older lepidoptera books. I know of no one who practices it these days and I am sure that any of the nuances of that unique method have probably been lost to time. Perhaps, some old notebooks may hold some secrets to the methodology but, where they may be is anyone's guess.

I have seen seven or eight really well prepared "inflated" larvae present in the collection of the museum where I once worked. That was all that were there from the collection of one individual.

I would postulate that it probably took that collector several tries and several larvae just to wind up with one particularly nice example. A meticulous and tedious affair to wind up with so few (present) in his collection.

Yes, photography is the way to go and the wonderful live shot of that larvae on a leaf is example enough for anyone.

[Cabintom]

Yes, photography is the way to go and the wonderful live shot of that larvae on a leaf is example enough for anyone.

Replace "larvae" with "butterfly" and I think you'll quickly understand why I disagree with this line of thinking (even though I'm not a collector of larvae).

[Chuck]

Update: I delivered almost forty frozen specimens of Finger Lakes region Tigers to Mr. Genetics. They span from early July through late August.

Morphologically, I see a trend toward "more canadensis looking" in early July, and "more glaucus looking" in late August, but the reality of it is 90%+ of the specimens from 2022 have mixed attributes so it's impossible to say which are Spring form glaucus, which might be MST/ Late Flight, which, if any, are Summer form glaucus. I did note that specimens from the northern most reaches of the Appalachian Plateau are larger. That said, I can pull two specimens from the same place, same day and one looks "MST" and one looks glaucus.

The flight period(s) in 2022 are useless to prove anything. Hagen's 1985 paper on the late flight ("Polymodal") has nice charts over several years showing discreet flight periods. My 2021 experience was June was cold and wet so nothing flew; in 2022 June was slow but the population from late June through late August was nothing but up, up, up.

In all thus far, I've been unable to prove any hypothesis. Very frustrating. Often what I see in recent data contradicts "the obvious" inferred by past years' data.

The general consensus amongst those who've studied Tigers over the past 40 years is that there are likely multiple "tribes" or groups of Tigers that developed along the lines of Papilio appalachiensis. Which, if any, of the Finger Lakes Late Flight populations are more Appy-like than glaucus I hope we'll known in a few months.

What flies in early Spring (2nd and 3rd week May) remain unknown. In 2022, like every year, I get one shot; and in 2022 like every year, I blew it. This too is very frustrating- I see them, but they don't alight; I spent many days in the field mid-May through June with ONE capture. Next year I'm going to try decoys.

One big take-away (and this reflects on another thread about the lack of observed butterflies in Panama) is that the Tigers have a preferred nectaring plant at any given time starting in late June, and which plant it is changes over night. This also varies regionally. So if one is, as I was, targeting Tigers, it would be very easy to see nothing or a few, when less than 1km away there are dozens nectaring. Once I picked up on this it became evident that it's not just the Tigers that have this routine.

Now, I have a paper to write to fulfill my collecting permit, and I think not a one of the questions posed in the application are answered. I have nothing really concrete to offer, unless "I dunno" is concrete. LOL.

[Chuck]

Gotta think some things through sometimes.

@eurytides wrote me If it turns out to be a new species, you will have the largest collection and should probably designate that as a type series.

@!&%% I hadn't thought of that! Then I'd have to give them all away post haste! Oh no! Which reminds me, I'm working on a different publication and when "somebody" sees the images they're going to want some of those specimens too. Everyone is always taking my type specimens.