Same story at the Arsenal on Monday. I was birding with out of town visitors and we were transfixed........
On Tuesday, September 19, 2017 at 1:35:19 AM UTC-6, SeEtta wrote: > > This was posted on Arthropods Colorado facebook group tonight regarding > the Painted Ladies: > > "Kate Hogan > <https://www.facebook.com/kate.hogan.7169?fref=gs&hc_ref=ARQCxKx90DU4Yl_gV91LEk2Ku_v723Rzmp9Kr0kWUPtfcc1PSl8jh-7KNHu_HamFQrY&dti=381476328587993&hc_location=group> > > A note about the Painted Lady phenomenon - I am colleagues with Dr. Mike > Weissmann who consults on butterfly houses all over the world and started > the Butterfly Pavilion - he shared this with me today: "This is an unusual > population burst that really has more to do with their success locally and > I don't believe is related to any migration. Painted Lady butterflies in > our area are originally from the Sonoran region of northern Mexico and > southern Arizona/New Mexico/California. There they live year-round, and > their population grows during our winter. In the spring, they migrate north > as the weather warms and their food resources in the Sonora become > depleted. This is a one-way migration, and they repopulate the USA each > spring this way. If they had a mild/moist winter with lots of host plant > growth and a low parasite load, we see a massive migration moving north in > the spring, around the time that the lilac bushes are in bloom. If we have > a good spring with lots of nectar and hostplants (they like thistle around > here, but their normal hostplant is mallow and related species), then they > are able to reproduce in fairly large numbers here. What we are seeing now > is the result of a mild local summer with lots of early-season moisture and > a low parasite load creating the right conditions for their population to > explode here, even though their numbers in the spring during the northbound > migration weren't record-setting. Also, the rabbitbrush is in full bloom, > so they have a lot of nectar to keep them going, as well as a great spot to > congregate where we can see a lot of them feeding all at once. However, > this is not like the monarchs heading south - painted lady butterflies have > a one-way migration. Those you see flying around and any eggs/larvae they > produce will die when the frosts come. Meanwhile, the home population in > the Sonoran region will continue on, and next spring more will migrate > north to temporarily repopulate our area again." > > > > > SeEtta Moss > > Canon City > > http://BirdsAndNature.blogspot.com > > On Mon, Sep 18, 2017 at 8:57 PM, Art Hudak <[email protected] > <javascript:>> wrote: > >> Extreme migration/dispersal. On 9/16 I observed 100,000+ combined at >> Centennial park, Harriman lake park and Belmar park. At one point at >> Centennial in a field of 10,000+ 50+ were on me, all clothing covered, >> boots, pants, shirt, arms, hat... >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Colorado Birds" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/cobirds/513cc392-dcdc-4dd1-baf2-32088cf155af%40googlegroups.com >> . >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/294c1c20-25cb-491e-9b24-7d459be344e3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
