Red Admiral Butterfly

Red Admiral Butterfly

American Lady Butterfly

American Lady Butterfly

Painted Lady Butterfly

Painted Lady Butterfly

West Cost Lady Butterfly

West Coast Lady Butterfly

This is a web site to coordinate observations of territorial behavior, migration, life history, population studies, seasonal variations in abundance and body size, and number of broods per year (voltinism) of butterflies in the genus Vanessa, including Vanessa atalanta, V. cardui, V. virginiensis, V. annabella, V. tameamea, and V. kershawi. (Red Admiral, Painted Lady, American Lady, West Coast Lady, Kamehameha Butterfly, and Australian Painted Lady).

Although the lady butterflies of the genus Vanessa are not as familiar or as well-studied as the Monarch (Danaus plexippus), their behavior and migration are likewise well worth observing. Much remains to be discovered about their habits and how their behavior and seasonal distribution varies by geographic location. Observers and experimenters ranging from casual to serious can discover new and valuable information about these butterflies. The list above links to more detailed information, including summaries of published findings and methods for observing these fascinating butterflies.

Royce J. Bitzer, Ph.D., Department of Plant Pathology, Entomology, & Microbiology, Room 504 Science II, 2310 Pammel Drive, Iowa State University, Ames, Iowa 50011, U.S.A.
Phone: (515) 451-9057   e-mail:

This site was most recently updated on August 23, 2023.

Recent News

August 23, 2023

Today, August 23, is Ukrainian National Flag Day, and tomorrow, August 24, is Ukrainian Independence Day, marking 32 years for Ukraine as an independent country.  

As my way of celebrating these Ukrainian national holidays, I encourage you to visit the iNaturalist project page, Lepidoptera of Ukraine.  Ukraine is quite the biodiverse country, from the montane conifer forest of the far western Carpathians to the central European mixed forest of the northwest, the forest steppe of the northeast, the open southern grassland steppes, and along the southern coast of Crimea, the Submediterranean Forest Complex.  This great diversity likely yields correspondingly diverse communities of butterflies and moths.

Last but not least, I've been amazed by how many Ukrainians have been posting observations on iNaturalist, despite the ongoing events of this terrible war.

-- Royce Bitzer

April 10, 2023

Spring has arrived here in Iowa, and so have the butterflies, including Red Admirals.  After the last three years with low numbers, it’s now looking like 2023 is going to be a more active, abundant, and exciting year for Red Admirals.  I’m still not sure how the Painted Lady population will develop this year, owing to the unusually intense and variable weather in California this past winter.

Red Admirals are now arriving in the upper Midwest, following two strong and very stormy weather systems that transported warm, moist air from the Gulf of Mexico into our area.  Red Admirals arrived soon afterward, with the first report from Omaha, Nebraska on April 4.  I spotted my first ones here in Ames, Iowa on April 7.  It’s likely they were here sooner, perhaps as early as March 31, but it was difficult to tell because cold weather followed each of the two frontal passages.  Since then, I’ve started receiving more reports from around the upper Midwest.

As always, I’m seeking not only first sightings of Vanessa species, but also sightings of migrating butterflies and sightings throughout the season.

-- Royce Bitzer, April 10, 2023

November 7, 2022

Two updates:

All links to images on our site have been restored.  Links had been broken for the past several weeks as a consequence of switching the site to a different server.

We have a new mapping platform for our interactive map - Leaflet.  Leaflet is based on Open Street Map and was created by Volodymyr Agafonkin, a Ukrainian citizen from Kyiv.  More information about Leaflet can be found here.  The available map formats include a street map and a terrain map, with the terrain map as the default setting.

--Royce Bitzer, November 7, 2022


September 26, 2022

A southward Painted Lady migration has been underway in central Iowa for at least the past three days. After a summer with none observed here, a few appeared in late August into mid-September, and then recently, larger numbers arrived after September 21. Although most have been spotted nectaring, several have been seen flying southward after the passage of a cool front on September 24. As of today, September 26, winds continue blowing from northerly directions, carrying Painted Ladies southward at heights of from 5 to 10 meters/15 to 30 feet.

--Royce Bitzer, September 26, 2022

April 27, 2021

I've received an e-mail from a friend who was wondering when Red Admirals would be arriving in the upper Midwest this spring.  He had not seen any postings of that species on the Wisconsin Butterflies recent sightings page, or on iNaturalist, and asked me how unusual it is to not see Red Admirals this far into the season.

The first Red Admirals in central Iowa have been later than average this year (the average arrival time here is in mid-April, but the first one can arrive as early as late March to as late as mid-May).  There have been several possible reasons for this:
1) It has been a generally cold spring until now.
2) Whenever there were warmer temperatures above 60 F with southerly winds, the air was very dry.  They prefer not only warmth and winds from the south, but also sufficient humidity, with dew points above 55 F.
3) The jet stream for the last few weeks was passing from central Texas through Mississippi, Alabama, and Georgia and then into South Carolina.  This pattern kept the warm, humid Gulf air well to our south, and brought several weeks of rainy, stormy weather to those states while we in the upper Midwest stayed unusually dry.

All three of these factors changed yesterday, April 26.  A loop in the jet stream moved northward, which allowed southerly surface winds to bring warm, moist air into our area.  Not only did the temperature rise rapidly into the low 80s, but the dew point also gradually rose from 41 F before sunrise to 56 F in mid-afternoon.  So yesterday was the first day this year that was favorable for Red Admirals in our area to be active and to migrate.

This spring I've been out checking the Iowa State University campus for Red Admirals each sunny or partly sunny afternoon above 60 F since late March, without finding any.  Likewise, there were none on April 25 - it was still too cool and dry.  But when I went there yesterday, I found the first one of the season, perching on and patrolling around the sunny west wall of Catt Hall.  It was a pleasant surprise, but one also anticipated due to the favorable conditions.  Now, as spring continues and  the weather becomes more favorable, we can expect more Red Admirals to be arriving in the upper Midwest.

Here is a dew-point map for 1 p.m. Central Daylight Time, April 26, showing the warm, moist, southerly air flow into the upper Midwest (attribution: RAL Real-Time Weather Data, National Center for Atmospheric Research,

Also note the dry line running from southwest Texas to western Kansas.  Here the moist air from the Gulf of Mexico meets dry air from the desert southwestern states.  Thus this line is likely to be the farthest possible western extent of any ongoing Red Admiral migration at this time.  The dry line is also notorious for spawning severe thunderstorms and tornadoes along the moist side of the line.

-- Royce Bitzer