Total Lack of Monarchs in Baltimore?

[aspawn]

We have been tagging in northern Baltimore City for the past 5 years. We have constructed a waystation with a large amount of milkweed and nectar plants, and each year we have seen our number of tagged individuals grow - last year, we raised 130 and tagged 100 of them.
This year, however, my students and I have been distressed to find not a single larvae in our milkweed patch. We began looking in early September, and have found nothing - our milkweed is pristine and uneaten, and we haven't even seen any egg-laying adults.
One complicating factor is that we did release ladybugs into the patch three times during the summer, to control an aphid infestation that really knocked back our milkweed last year. We still have very large numbers of ladybug larvae on all of the plants. We also have also been overrun by globe milkweed, after a colleague donated one plant as a curiosity, which this year has outcompeted our showy and tropical milkweeds. It was our experience last year that larvae don't feed on globe milkweed.
We saw good numbers of adult monarchs in the patch all summer, and had a big caterpillar population in the spring. Has anyone seen monarchs during September in Baltimore? I'm guessing that the ladybugs preyed on caterpillars as well as aphids, but the lack of adult butterflies has me puzzled. Did the migration go through early?
Thanks for any feedback you can provide.

[Mona Miller]

Hurricane Hanna went through here pretty hard. We had winds of 40-60 mph and 8-10 inches of rain. Also this year I am noting European Paper Wasp and other paper wasp patroling through the milkweed patch searching for caterpillars. There has been an explosion of stink bugs this fall, too. I did net two females going through in late August and they both had heavy OE. The last batch of eggs that I collected out of my garden only 1/3 of them hatched.

I had promised a teacher in Woodbridge, VA to help her with some caterpillars, but finally had to tell her to order some on line. I had none to give her. So far, this year I am not seeing the numbers of Monarchs in Herndon that I saw in previous years. If the migration is late, this year--it is very late or has bypassed us.

Monarch Teacher Network
This is an international program which includes Canada, USA, Mexico, Peru, and New Zealand
http://www.eirc.org/website/Programs-+a ... r-Network/

http://monarch.pwnet.org/
Monarch Live = A couple of USA film makers will be following the migration of the monarch and broadcasting it live via satellite feed to class rooms this year. Live from Mexico.

[Mona Miller]

viewtopic.php?f=7&t=1439
I posted some sources for native milkweeds.

A friend in Woodbridge, VA also had the swan plant (Asclepias physocarpa) reseeding naturally this year. Our winter was rather mild, so in her town home community people had volunteers coming up here and there and every where. They do use it at Meadowlark Gardens in Vienna and also at my house where I never seem to get it to seed before frost comes. I'd recommend pulling it out where it is not needed, but on the other hand the tropicals are still green when our native milkweeds are usually spent.

It also reseeds in New Zealand where it is the primary food for their Monarch population.
http://www.monarch.org.nz/monarch/

[Mona Miller]

I was out washing the aphids off my tropical milkweed today and found 21 caterpillars. Keep a check on your tropical milkweed, they just might be there now. I wouldn't mind sharing a few if you need them. I do have my permit for Maryland.