Polyphemus Moth Eggs Arrive

We have decided to rear the Polyphemus Moth (Antheraea polyphemus) from eggs for the first time.

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Today we had 40 Polyphemus Moth (Antheraea polyphemus) eggs arrive from a breeder in Pennsylvania (coincidentally the same one who sold us the Ceanothus Silkmoth [Hyalophora euryalus] eggs too!). The eggs were stuffed with tissue paper in a plastic case wrapped in lined paper and came by envelope, the exact same way that the Ceanothus eggs were packaged. We had actually ordered 3 dozen eggs (36) but received 40, a few extras as always to compensate for any unhatched eggs. After removing them from the plastic case, we placed them in a small petri dish and put it in a safe place in the house that doesn't get direct sunny that could kill the eggs. However, while doing this we noticed that one of the eggs was already clearly dead for some reason since it was shriveled up, but the other eggs look plump and alive (we assume). We don't know why one died but all is well since our generous seller had provided us with four extra eggs so we still have 39. He did not tell us when they were laid, but we can probably assume it was within a week before we contacted him which was 7/11. That means they should begin hatching either this week or the following week.

Below are pictures of the eggs with a closeup version as well. The eggs are varying shades of brown, with some being almost white as shown in the bottom row. They are flat unlike the Cecropia, Ceanothus, or Luna eggs we have had. There is also a brown ring along the edge.

The Polyphemus Moth is the largest Giant Silkmoth (subfamily Saturniinae) that is native to our region with a wingspan approaching six inches. It is also the most widespread as well, being found in all 48 continental states except for Nevada and Arizona where it is replaced by the very similar and related Oculea Silkmoth (Antheraea oculea). As always, however, our Alameda County just doesn't seem to be a particularly good place for Lepidoptera in the Bay Area because it consistently has some of the lowest number of sightings compared to neighboring counties for a lot of species on BAMONA with only two sightings of the Polyphemus Moth -- one of which was dead while the other was a caterpillar. Since we haven't been able to find it in Albany or nearby cities despite living here our entire lives, we had to resort to obtaining them elsewhere, just like with our Ceanothus eggs. It's really truly unfortunate that we live in an area that just seems to be one of the worst places for Lepidoptera hobbyists since most all the popular species (as well as hobbysists) are found in Eastern North America. 

This is actually not the first time we have purchased this species before; back in the fall of 2009 we bought six diapausing Polyphemus cocoons that eclosed the following spring, but as this species does not mate readily in captivity unlike many other Saturniidae, and we had not learned how to hand-pair Lepidoptera before, we failed to obtain ova from them. This year we wanted to have another shot at this species again, this time straight from eggs, because we really only have a year left before we graduate from high school and wanted to try this popular Silkmoth species while we still have the time. We've read many nice things about this species from sources online and it should be among the easiest Silkmoths to rear along with the the Luna Moth (Actias luna), that we reared quite successfully in 2013. Surely, it will be easier to rear than the two Hyalophoras we are currently rearing right now that are apparently harder and more disease prone species to rear (alas, our euryalus do not look like they will make it to cocoon, let alone moth). 

We wanted to rear Polyphemus caterpillars now during the middle of summer because we want them to diapause rather than create another brood this year. They are normally bivoltine in a lot of places, but can be uni- or multi- voltine as well. Ours came from Pennsylvania where they are bivoltine, so the eggs we received, at least according to the seller, are probably late first brood or second brood eggs. In either case, we plan to overwinter them by subjecting them to a diminishing photoperiod.

As far as host plants go for the Polyphemus caterpillar, we have a lot of choices since this species eats a huge variety of trees and shrubs, but it and its Old World relatives seem to be associated most with oak (Quercus), which is what our seller uses in Pennsylvania. However, the only native oak species we have here is the Coast Live Oak (Quercus agrifolia), an evergreen variety with small, tough, and prickly leaves that doesn't seem as good of a host as the deciduous oak species that are more common in other parts of the moth's range that have large, smooth leaves. We are not even sure if the Polyphemus Moths native to California normally utilize it or not, but nonetheless we will try to rear them on this since it is a Quercus after all and is quite abundant around our neighborhood. However, there are a few landscape oak trees with the large, smooth leaves (not exactly sure what species) that we could use but they are several blocks away from our house. There are also a few alternatives hosts that are somewhat common around here such as willow (Salix), grape (Vitis), plum (Prunus), but obtaining a large supply for the older caterpillars could be a hassle and these are probably less preferred hosts. We will try to go with either the Coast Live Oak or the deciduous oak species.

- Alan