Questions on which generation occur by me.

[keithpetrosky]

I was wondering, the monarchs I find on Long Island, NY, what generation are they? Are they the generation that migrate to Mexico? I usually see them in bulk here during July,August, and more less in September.

[Mona Miller]

If you are seeing them for the first time in July they could be second to third generation. They start hitting the USA in late March to April. We used to see them here in Virginia in late April. Last year I had a Monarch show up in mid May. She looked like she had traveled from Mexico. In a good year, we might even see 6 generations. I sent a group of Monarchs down to VA Beach on November 4 via express mail. It was too late for them to travel out of the area.

In mid to late August we start getting migratory Monarchs. But, the problem is that you can get reproductive Monarchs that are pushed South by the cold. You can have Monarchs in diapause and also reproductive Monarchs traveling in the same direction.

[keithpetrosky]

They start hitting the USA in late March to April.

I know for a fact that's too early here for them, March NY can still get snow an April we get frost sometimes, May is usually when we start seeing all of our insects like caterpillars and butterflies.

I have observed monarchs laying eggs here usually in July or early Auguest, so I think that was the 3rd generation, and their offspring migrate from the 4th.

[Mona Miller]

The latitude for Long Island, New York is 43. Peak migration times for your area are September 3 - 15; September 11 is the midpoint. That is when you should tag and that is when you would probably find Monarchs in diapause.

http://www.monarchwatch.org/tagmig/peak.html
Peak Migration Dates

These vary a bit from year to year. They can start earlier or later.

[keithpetrosky]

Great thanks, that was very helpful!

[Paul Cherubini]

We used to see them here in Virginia in late April.

In warm years like 1997 and this year they still do show up in Virginia in late April:

[Mona Miller]

Paul Cherubini,

According to one of the greatest Monarch scientist, Dr. Fred Urquhart, they start traveling from Mexico in late February. That would be enough time to make it here. And, Dr. Fred Urquhart used to tag Monarchs in Mexico and had a remigrant picked up in NY that is beyond where I live.

Or is it one of those pesky farm raised butterflies messing up the natural data. I'll be testing them for OE when they emerge.

[Paul Cherubini]

Or is it one of those pesky farm raised butterflies messing up the natural data. I'll be testing them for OE when they emerge.

You already said the wild female you saw today was faded, hence old, hence has already laid alot of eggs, hence will leave behind many valuable offspring.

Good thing no monarch enthusiast caught her early in her life, because some enthusiasts (not me) like to test adult monarchs for OE and then freeze them if they test positive.

[Mona Miller]

Paul Cherubini,

Can you prove that this isn't a farm raised butterfly? I'd say no.