Rearing Notes and Stats 8/20/16-8/27/16:

Stats:
Encounters this year:

• Eggs (21) Difficult to identify whether they are Red Admiral or Satyr Comma
• Larva (21) 
• Pupae (1) 

Locations:

• Tilden Regional Park District, Berkeley, CA (E21) (L21, P1)               

Months:​ ​​

• July (E19) (L10, P1)    ​    ​
• August (E2) (L12, P0) 

- Brian

Today, the first of our many tachinid fly (Tachinidae) pupariums emerged. It originally parasitized one of our Gulf Fritillaries (Augraulis vanillae).

On 7/2, we found out that one of our wild caught Gulf Fritillaries was parasitized. Three maggot bit their way out of the chrysalis and pupated. They were huge pupa, quite obviously some kind of tachinid fly and not a parasitoid wasp which are often much smaller and come in huge numbers. 

For such a small insect, it would be logical to assume that the tachinid flies have a fast life cycle. We expected that the pupariums eclose within a week or two. But it took over one month for even one of them to emerge! We're not even sure whether the other ones are even still alive (we have gather quite a lot of them from outer wild caught chrysalises over this past month) or they really do take such a long time. 

After the fly emerged, we put it in the freezer. The scary part about parasitoids is that they look surprisingly similar to their non-parasitoid counterparts, just usually smaller. This tachinid fly has the same basic appearance as any other harmless fly you see around. This makes it just the more important to keep the pupa after they come out so you can see and document what they eventually become for future reference!

- Brian

Rearing Notes and Stats 6/28-7/12:

7/5-7/6:  Nothing significant worth noting.

- Brian

Today we witnessed three huge tachinid fly (Tachinidae) larvae crawling out of one of a Gulf Fritillary (Augraulis vanillae) chrysalis from a wild-caught caterpillar.

Virtually every species of caterpillar have natural parisitoid enemies. Some species are routinely parasitized such as Monarchs (Danaus Plexippus) with tachinoid wasps (Tachinoidae) while it can be rare in other species. For the record, we have never had any problems with wild-caught Gulf Fritillary (Augraulis vanillae) caterpillars being parasitized -- until today. 

Today we had the honor of witnessing three ridiculously fat maggots eating and crawling their way out of our oldest Gulf Fritillary chrysalis that pupated on 6/29. The chrysalis was made by a wild-caught caterpillar that we caught in fifth instar which we noticed was significantly smaller than the three other wild-caught fifth instars we had (so far, we don't think these three have been parasitized). Being undersized is a typical symptom of being parasitized for pretty obvious reasons -- they are being eaten alive by the parasites!

After the maggots came out, they hardened into extremely round, dark brown pupariums. There are endless species of parasitoid wasps and flies (order Hymenoptera and Diptera) and it is close to impossible to identify them down to the exact genus and species until they emerge, and even then it is difficult. But we can say pretty safely that they are  probably just tachinid flies since parasitoid wasps rarely get this big. When they emerge a week or so later, we will be sure to take some more pics and report back!

- Brian