Polyphemus Notes

Many thanks to those who have been responding regarding flight times for Antheraea polyphemus. I am organizing responses alphabetically according to states and provinces:

British Columbia:
Dean Morewood writes:

I agree that polyphemus is univoltine in Canada, with adults flying late May to July (a little later than Hyalophora euryalus adults in B.C.), but want to note that diapause in this species is facultative. I might be able to dig up a few references, but can vouch for this from my own experience.

A few years ago I reared a small brood of polyphemus in southwestern B.C. (local stock). I ended up with about a dozen cocoons and, having reared the larvae indoors, all of the adults emerged in August!

California:
David Wikle confirms A. polyphemus from Cloverdale in Sonoma County with female taken at lights on August 24, 2003.
This is probably from a June flight.

David Gaban writes, May 29, 2003, "I can confirm from personal experience A. polyphemus and H. euryalus occur in San Benito County, CA."

Hernan Espinoza from the Stanford Biochemistry Department confirms with a picture, Antheraea polyphemus June 1, 2003, on the side of the Beckman Building at Stanford in Santa Clara County.

Chris Conlan writes from San Diego County, "Antheraea polyphemus does occur here but it is not common and tends to only be on the wing in spring. I have specimens to prove it that were taken right at my back door."

Non-member Sharon Wilson from southern California: Orange county, Yorba Linda, California, writes, "I found a female Polyphemus moth on the 20th of May 2008. She laid eggs and they hatched in about 11 days. There were 23 caterpillars. I now have 16 cocoons, the others didn't make it. They seem to die at different stages of their development. There is still one that seems to be developing very slowly, so I don't think it will make it either. I don't know if something has gone wrong or what. I was under the impression that the cocoons would hatch in 3 to 4 weeks. It's been just over 4 weeks (August 15) for the first cocoon and nothing has happened. How long should I wait before I know they didn't make it?"

Florida:

On January 30, 2004, in Palm Bay, Florida (Brevard County) a female polyphemus was observed at a laundramat by non-member Joan Molozaiy (even the moths have to wash their socks!), so it would appear this species is on the wing all months in Florida, and probably in south Texas too!

Eggs from the female polyphemus reported above on January 30, 2004 have hatched, so there had to have been a wild male on the go as well.

Non-members write:

On January 25, 2003, I received a report of a pair of polyphemus in Florida. Adult moths were seen in the same area in late November.

Today (February 24) my wife and I saw this moth (Antheraea polyphemus) outside a laundromat in Naples, Florida, at about 1 PM EDT. It was our first observation of this beautiful creature and quite exciting for us, especially my wife. It seemed to be disoriented or groggy, but when we left it, it seemed to be OK hanging onto a branch of a hedge. I just thought you might like to know of this sighting.

Don Ehlen writes, "I can confirm polyphemus for Florida counties:
Palm Beach Co., West Palm Beach, 10 November 1996 "

Louisiana:
Vernon A. Brou writes:

Voltinism of Antheraea polyphemus (Cramer) (Saturnidae) in Louisiana

by

Vernon Antoine Brou Jr., 74320 Jack Loyd Road, Abita Springs, Louisiana 70420

USA email: vabrou@bellsouth.net

"In Louisiana, Antheraea polyphemus (Cramer) has been captured during the months February through October at ultraviolet light traps. Numerous authors have reported that this large and fairly common North American silkmoth species has one brood in its northern range and two broods in the southern United States. In my 26-year Sphingidae study (Brou & Brou, 1997), I discovered that for over a century authors assumed most North American Sphingidae had one brood in northern states and two broods in the southern states. It was very apparent when reviewing a century of sphingid literature, that later authors simply parroted what was previously stated. Some statements, including punctuation, were word for word copies of earlier author's statements. No one actually questioned the validity of their statements, assuming them to be factual. It appears the same situation occurs regarding the Saturnidae of North America.

"Even in our most prestigious Moths of North America series (MONA), Ferguson (1972) stated of polyphemus, 'As far south as Florida, there still seems to be only two broods ... February to April ... October to December.' The question then becomes, to which brood do the May, June, July, August, and September specimens belong. Covell (1984), stated polyphemus has 2 broods, April and September, without further explanation. In Louisiana, polyphemus actually has five annual broods at approximately 47-day intervals beginning with the first brood peaking about mid-March."

Vernon's article/data indicates that moths begin emerging from diapausing cocoons in February with a peak flight in mid March from overwintering stock. The first brood of the new year emerges end of April to early May; the second brood adults appear mid June; third brood moths appear end of July with another peak flight (fourth brood) in mid September. Larvae from this fifth brood develop, spin cocoons (most likely near end October or early November), and then diapause until February-March flight.

A non-member writes:

On January 30, 2003, I received a report of an outdoor polyphemus emergence from Baton Rouge, Louisiana on January 29. I suspect there is at least a partial sixth brood in La., or changes in weather patterns are creating changes in flight seasons.

Massachusetts:
Don Adams writes:

"My polyphemus stock had a very extended season in 2002 with first eclosure, from cocoons kept outside under totally natural conditions, on 30 May and last on 27 July. Had very good luck calling wild males during this entire period. As in past years, had a few double-brood eclosures late in Aug, but no wild callings or pairings from these. I believe polyphemus to be marginally double brooded here in southeastern Massachusetts, but have been able to prove Saturniidae bivoltinism here conclusively only with Actias luna."

Don Adams writes (July 29, 2010), "For the first year in many here in W. Bridgewater, yesterday, three female promethea and one female poly, raised from spring 2010 eclosed parents, popped out of their cocoons, and last PM or very early this AM the poly called two beautiful wild males and is paired with one of these. The female will lay eggs this PM, and cats are easy to raise on Red or Black Oak."

Michigan:
Jeff Ausmus writes:

"About Polyphemus in my area: I am in Erie, MI, which is in very Southeast Michigan, about 5 MI north of Ohio and 3 miles west of Lake Erie. Here, I've had polyphemus come in to scenting females at the following dates:

2001
June 5, 7
July 23, 28, 29, 30

2002
June 12, 17, 18
July 5, 6, 13, 14, 20

These definitely suggest 2 wild broods in this area, and from the actual moths that I raise... they always have 2 broods. I've also consistantly noted an interesting thing about the times the moths come in between broods.

In the 1st brood, the males always seem to come in around midnight, between say 11:00PM and 12:30AM. In the second brood, they begin coming in at about 1:30AM and don't quit until 4:00 or 5:00AM I found that interesting.

Hope this information is helpful to you!

Don Ehlen writes, "I can confirm polyphemus for Minnesota counties:
Sherburne Co., Big Elk Lake, 2 June 1991"

New York:
Spider Barbour writes:

"In the mid-Hudson Valley of New York (Eastern Ulster County, Dutchess County, Orange Co., Rockland Co., Westchester Co.) polyphemus is both univoltine and bivoltine. I suspected this after finding a couple of eclosed cocoons in September that were wrapped in dry (but green!) leaves, obviously same years' growth.

Confirmation came when I found a 5th instar caterpillar on gray birch on 25 July 2000 in Fishkill, Dutchess Co. NY. Within a few days the caterpillar began spinning. The cocoon produced a female moth on 17 August, which attracted a male that night, and began laying eggs the evening of the 18th, after which I released the female to oviposit in the wild. I reared about 30 of the caterpillars, which began spinning at the end of September through mid-October.

The same year (2000) I collected 22 wild polyphemus caterpillars over the period from 3 September to 5 October. These produced moths in 2001 that began emerging about the third week in May, and continued into mid-July. The reared polyphemus (from second brood parents) emerged throughout the same period, though there were more early than late emerging adults.

2002 had a similar emergence period, but with more cocoons (about 90) I was able to discern a pattern: an early surge from about 18 May - 8 June, few emergences between 10 June and 25 June, then about 60% of all emergences from 25 June to 15 July, a drop and tapering off, with no first-brood emergences after 30 July. Then from about 8 August through 25 August the second-brooders emerged from cocoons spun 15-20 days earlier.

It's interesting to be in what appears to be an overlap zone between single and double-brooded polyphemus. Many questions are raised about the determinants of uni- vs. bivoltinism. For example, to what extent is voltinism determined by genetic, and to what extent by enviromental factors such as photoperiod, ambient temperature, humidity, nutrition, etc.?

Feel free to share this with other members.

Best,
Spider"

Tim Dyson writes:
"Here near Peterborough in south/central Ontario, the earliest and latest I have seen polyphemus at lights is May 24th and July 30th."

Hence, there may be a partial second brood in southern Ontario in years when spring comes early and summers are warm. Bill Oehlke

Don Ehlen writes, "I can confirm polyphemus for Oregon counties:
Jackson County, Colestin, 6 July 2003;
Lane County, Elmira, 1 July 1995."

Bill Oehlke (Prince Edward Island, Canada writes:

Here on Prince Edward Island in eastern Canada, I sometimes have wild polyphemus males fly in to calling females in late May and still occasionally take females at lights as late as July 10. The polyphemus are definitely single brooded here. Eggs incubate for about twelve days and larvae consistently feed for six to seven weeks before spinning.

If I have research orders for summer stock polyphemus, I have to bring in "earlier" eggs from a more southern locale, and rear them indoors for a week or so before putting them out in sleeves and hope we don't get a hard frost.

Summer stock usually emerges about fourteen days after spinup.

I was very surprised one summer to see lunas, columbia and polyphemus at lights near Saint John, New Brunswick, as late as July 16-17. I think the cool ocean breezes delayed an early spring emergence and then warm breezes, off a summer-heated sea, allowed for longer development into the fall. Maybe they are double brooded in southern New Bruswick, but I doubt it. Two weeks in egg stage, six weeks in larval stage, two weeks in cocoon stage would mean second brood moths flying in mid-July would have come from parents that emerged seventy days earlier, around May 8. There is often still snow on the ground that time of year and nights are generally much too cold for moths to be flying.

Tennessee:
Bruce McCarty writes:

In eastern Tennessee, during the past several years the first eclosures were in late April and early May. The second group emerged in mid-August.

Texas:
Mike McCormick writes:

I have routinely seen flying moths as early as early March and as late as early November here in the Houston area of Texas. I'm sure that the time of spring emergence will be a function of the kind of winter we have.

Texas:
Joe McKoy writes:

From a captive female, I collected 78 ova March 22, 2002. Nine days to hatch (3-31-02), and larval stage ran an average of 33 days (to 5-3-02) feeding on Quercus stellata (Post Oak). The pupal stage ran 30 days to the first female (6-2-02). That female took 4 days to mate and lay (6-6-02).

Second generation was laid on 6-6-02 and hatched in 9 days on 6-15-02. So the 1st generation took 76 days start to finish. I did not hold any polyphemus beyond the 6-15-02 hatch. I assume the 2nd generation would take about 76 days which would put us at August 21, 2002. Weather conditions would certainly hold another 76 days up to November 4, but that's probably the limits of favorable weather. I don't know if a third generation occurs here or not (Central Texas, east of Austin) but two three generations seem certain.

Texas:
Jim Klinger writes:

Flight times in Dallas, Texas, for Antheraea polyphemus:

Last year: March 23rd wild hatchings. Many matings the next morning.
72 days later, June 2nd: few wild hatchings. Few matings the next morning.
83 days later, September 24th wild hatchings. Large number of matings the next morning.
69 days later, December 2nd few wild hatchings due to 80 degree warm spell. One wild male flew to cage.

These dates are basically the same each year. Very easy to predict when storm systems approach during these dates.

It would appear that there are three broods annually with at least a partial fourth brood, when weather conditions are favourable.

Don Ehlen writes, "I can confirm polyphemus for
King County, Carnation, 18 June 2000;
King County, Seattle, 2 October 1996;
Jefferson County, Quilcene, Early July 2002."

It would appear that there are probably two broods annually in Washington especially along inland waterways, where there may be prolonged warmth even into early winter.

Wisconsin:
An adult polyphemus came in to lights in Greenville, Wisconsin about 100 miles north of Milwaukee on June 5, 2003.

Return to Members' Articles

Return to Antheraea polyphemus

Go to Main Index