Pieris oleracea
In 3 days ~20% in a week ~50%
Pieris oleracea, or more commonly known as the mustard white, is a butterfly in the family Pieridae native to a large part of Canada and the northeastern United States. The nearly all-white butterfly is often found in wooded areas or open plains. There are two seasonal forms, which make it distinct from other similar species. Because of climate change, populations are moving further north.
As indicated by the common name, P. oleracea adults and larvae primarily feed on plants in the mustard family, Brassicaceae. The species is threatened by the rapid, and monoculture-forming, spread of the invasive species Alliaria petiolata, which is toxic to larvae. Populations of P. oleracea have been declining. It may be that this butterfly is slowly adapting to garlic mustard. However, it may not be a fast enough process to ensure its survival, due to the high level of aggression on the part of the plant and the continuing encroachment of human development.
Its specific name oleracea means "related to vegetables/herbs" in Latin and is a form of holeraceus (oleraceus). Pieris oleracea eggs are yellow and shaped like cones, with vertical ridges. Larvae that are mature... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Elk Island National Park | 🇨🇦 Canada |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Edmonton | 🇨🇦 Canada |
With luck
About 10% of wildlife watchers report a Mustard White sighting in Edmonton on a given day, based on 77 verified sightings from GBIF citizen-science data. It is the 36th most-seen of the 390 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
May
In that month about 20% of wildlife watchers report a Mustard White in Edmonton on a given day, against under 5% in September to April, the lowest months. That is one of Edmonton's wettest months, with about 65 mm of rain against 20 mm in February.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Mustard White sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Edmonton, in our data
Edmonton is the only city on Wallace's Line with enough records to rate Mustard White sightings: about 10% of wildlife watchers there report one on a given day.
GBIF citizen-science records
It is estimated from how often the Mustard White is recorded against all the insects logged in Edmonton (77 verified sightings), 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.
