June 10, 2016

During the last several days, the Red Admiral population in central Iowa has rapidly risen as the new summer generation butterflies have emerged.  The larger, darker summer butterflies are quickly displacing the smaller spring-generation butterflies from the territories that Red Admirals occupy in the evenings.  We have also been seeing some of these fresh individuals flying northward during the day, perhaps migrating, so observers to our north might want to watch for migrants from the south.  Also look for the local summer generation butterflies farther north to start emerging during the next few weeks.

Also, be aware that there may be especially large concentrations of Red Admirals emerging within a few miles or kilometers of rivers, lakes, or wetlands where stinging nettles, the larval foodplant, grow abundantly.  In late June and early July 2015, huge concentrations of Red Admirals appeared in at least a dozen locations in Iowa; most or all of these sites were near rivers or streams.  We will be watching for similar outbreaks this summer.  Observers typically report hundreds to thousands of Red Admirals swarming along roadways on either side of a bridge, or when canoeing or kayaking on a river.  So, if you see one of these outbreaks, please note the date, location, and its approximate size and report it to us.

--Royce Bitzer, June 10, 2016

June 09, 2016

We now have a Vanessa Migration Project page on for reporting sightings of Red Admirals, Painted Ladies, and other Vanessa species. If you often report observations to iNaturalist, or would like to post photos with your butterfly reports, our iNaturalist project page is another way for you to share your observations with us.

--Royce Bitzer, June 9, 2016

March 17, 2016

Two Painted Ladies were spotted in Ames, Iowa on March 10, 2016 by two different observers.  These sightings occurred nearly two months before the typical first Painted Lady sighting in early May.   Another early Vanessa sighting was of a Red Admiral at Point Pelee near Leamington, Ontario on March 16, perhaps a month earlier than is typical for that area.  The strong El Niño and unusual weather patterns this winter may be partly responsible for these butterflies' early emergence and arrival.  There may be more early arrivals in other places this year, so please watch for them.  What you think at first might be an early spring Comma or other anglewing could actually turn out to be a very early Painted Lady - so check carefully!

--Royce Bitzer, March 17, 2016      

February 17, 2016

The strong El Niño event in the Pacific Ocean this winter has given rise to increased rainfall in southern California during the past 30-60 days.  Rainfall has also been very heavy this winter farther up the Pacific Coast from central California to northernmost Washington State and perhaps further northward.  These conditions are very favorable to give rise to a potentially enormous spring migration of Painted Ladies.  Among this massive stream of butterflies may also be West Coast Ladies, Red Admirals, and perhaps even some American Ladies.  So please watch for them, share your sightings, and especially note flight directions and estimate numbers of butterflies you see.  With the several hundred (or more!) observations we anticipate receiving this spring, we'll have a good opportunity to trace some detailed patterns of butterfly movement as this migration unfolds.

--Royce Bitzer, February 17, 2016

July 06, 2015

Unified Butterfly Recorder (UBR) is an Android app that provides butterfly researchers and enthusiasts with a tool to use in the field to efficiently record butterfly sighting data. It was designed by a group of computer engineering students as part of a senior design class at Iowa State University in collaboration with the Entomology staff at Reiman Gardens. The purpose of the app is to allow the user a quick and efficient method to collect data across a variety of survey protocols traditionally used by researchers and citizen scientists in the field. The UBR has many unique and useful features, including automatically recording the time and location of each of your butterfly sightings, tracking your own survey route, and creating a map of your butterfly sightings. For more information, select "Population Surveys" from the primary links on the left side of this page, and then select "Unified Butterfly Recorder."

--Royce Bitzer, July 6, 2015

June 30, 2015

Have you noticed enormous swarms of Red Admirals in your area?  Observers throughout Iowa have been reporting huge outbreaks of Red Admirals along particular stretches of roadway, most of which are near the floodplains of streams and rivers.  One of the first of these outbreaks to be reported was discovered on the road west of Luther, Iowa, which crosses the Des Moines River.  The number of flying butterflies started increasing at the western edge of Luther, and seemed to grow exponentially for the next several miles until they peaked near the river, where perhaps several thousand butterflies were swarming at any one time.  They seem to be concentrated in a belt along the river and extending two to three miles on either side of it.

These butterflies had nearly all emerged recently, and had most likely fed as larvae on stinging and wood nettles that are especially abundant in floodplains.  If the kind of outbreaks now happening in Iowa are also occurring elsewhere in the Midwest or in other parts of North America, the Red Admiral summer generation this year could be enormous, perhaps one of the largest ever observed.

Royce Bitzer, June 30, 2015

May 06, 2015

The first arrivals of the western Painted Lady migration reached the Seattle area on April 30.  They had probably flown northward from where they had been concentrated in southern Oregon and northern California.

-- Royce Bitzer, May 6, 2015

May 06, 2015

Red Admirals have been migrating northward through Iowa in larger numbers beginning on Sunday, May 3. Some Red Admirals have been here for the past few weeks, but the larger numbers we’re seeing since this weekend appeared rather suddenly here in central Iowa on May 3, migrating northward, and they still continue to do so. They arrived in Story County, Pocahontas County, and doubtless in many other parts of the state at this time, flying toward the north-northeast. They probably came with the arrival of the first warm, humid air mass to reach our area this spring. When the winds picked up from the south, so did the butterflies, riding the wind flow northward from some as-yet-unknown area to the south.

Accompanying this wave of Red Admirals has been a relatively small number of American Ladies traveling northward with them.

From where have these butterflies been coming?  Have any observers in states south of Iowa been seeing this migration before May 3?

-- Royce Bitzer, May 6, 2015

April 28, 2015

The Red Admirals are out in central Iowa!  I saw the first one on April 17, but then it got cold for the next week and I didn't see any more.  But then we had a beautiful sunny day in Story County on Sunday, the 26th, and a group of us saw three flying around at East Peterson Park in the early afternoon.  Then yesterday on the 27th, I spotted three more while surveying the Iowa State University campus on another bright, sunny afternoon after 5 p.m.  So who else has been seeing them in Iowa or elsewhere around the Midwest?  Please keep us posted!

--Royce Bitzer, April 28, 2015

April 28, 2015

At this time in late April, Painted Ladies have been abundant in northern California and southern Oregon for at least the past two weeks.  Some of the butterflies may have been continuing to migrate northward in southern Oregon, but this activity was not definite - the butterflies were nectaring on dandelions, and most seemed to be flying northward when they left the flowers, but the direction wasn't as obvious as it had been in late March.

Are other people elsewhere in northern California and the Pacific Northwest seeing more Painted Ladies this spring?  What's happening in Portland?  In Seattle?  Elsewhere?  With more of us reporting, we can get closer to figuring out the actual extent and timing of this Painted Lady irruption.

-- Royce Bitzer, April 28, 2015


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