Helicoverpa zea
In 3 days ~20% in a week ~40%
Helicoverpa zea, commonly known as the corn earworm, is a species (formerly in the genus Heliothis) in the family Noctuidae. The larva of the moth Helicoverpa zea is a major agricultural pest. Since it is polyphagous (feeds on many different plants) during the larval stage, the species has been given many different common names, including the cotton bollworm and the tomato fruitworm. It also consumes a wide variety of other crops.
The species is widely distributed across the Americas with the exception of northern Canada and Alaska. It has become resistant to many pesticides, but can be controlled with integrated pest management techniques including deep ploughing, trap crops, chemical control using mineral oil, and biological controls.
The species migrates seasonally, at night, and can be carried downwind up to 400 km. Pupae can make use of diapause to wait out adverse environmental conditions, especially at high latitudes and in drought. The corn earworm is found in temperate and tropical regions of North America, with the exception of northern Canada and Alaska as it cannot overwinter in these areas. Helicoverpa zea found in the eastern United States also does... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Big Bend National Park | 🇺🇸 United States | |
| 2 | Point Pelee National Park | 🇨🇦 Canada | |
| 3 | Rocky Mountain National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Denver | 🇺🇸 United States | |
| 2 | Austin | 🇺🇸 United States | |
| 3 | Dallas | 🇺🇸 United States | |
| 4 | Chicago | 🇺🇸 United States | |
| 5 | San Antonio | 🇺🇸 United States | |
| 6 | Houston | 🇺🇸 United States | |
| 7 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 8 | Baltimore | 🇺🇸 United States | |
| 9 | Washington | 🇺🇸 United States | |
| 10 | Philadelphia | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Corn Earworm Moth sighting in Rocky Mountain National Park on a given day, based on 14 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 93rd most-seen of the 191 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
September and October
In those months about 20% of wildlife watchers report a Corn Earworm Moth in Rocky Mountain National Park on a given day, against under 5% in November to August, the lowest months.
Between midnight and 3 am
Across all the parks we cover, that three-hour window holds the most Corn Earworm Moth sightings with a recorded time, and about half of them come between 6 am and 6 pm: it is seen both by day and at night.
Among the best
Of the 3 parks where we can rate Corn Earworm Moth sightings, Rocky Mountain National Park ranks 3rd at about 10%, level with the leaders once rounded. The best odds are in Big Bend National Park (United States, about 10%) and Point Pelee National Park (Canada, about 10%).
Same family: Noctuidae
The closest relatives of the Corn Earworm Moth that you can see in Rocky Mountain National Park (family Noctuidae, Cutworm Moths and Allies) are White-Spotted Midget (about 10%) and Langton's Forester (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Corn Earworm Moth is recorded against all the insects logged in Rocky Mountain National Park (14 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
