Black Swallowtail
Place name abbreviations: MPEA – Middle Patuxent Environment Area; PRSP – Patuxent River State Park; PVSP – Patapsco River Valley State Park; UMDCF – University of Maryland Central Farm.
Click on the common name to obtain additional information from the Butterflies and Moths of North America web page and the following common name for additional information from USGS web page. BugGuide is another web resource.
Legend:
Common name [Link is to BAMONA] (wingspan range in inches) Common name [link is to USGS] |
Occurrence level & flight period. | |
Habitat. | Typically visits (for nectaring). | Larval host plants. |
Black Swallowtail (3.25–4.25″) Black Swallowtail |
Uncommon: May thru Aug | Open, weedy fields & marshes | Common milkweed | Queen Anne’s lace, parsley |
Life history of the Black Swallowtail by Bob Schaefer (Mount Airy, Howard County) 2012
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Egg on dill
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Small larva
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Growing larve
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Larva shedding skin
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Larva in familiar pattern but still with small spines
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Large larva
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Larva preparing to putate
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Pupa attached by thread
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Rear view of pupa
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Empty pupal skin
Black Swallowtails from Caterpillar to Adult
Kristin and Eric Trouton “had a total of 10 black swallowtail caterpillars on our dill! They ate all of our dill, and I also placed all of my parsley nearby and they ate all of that as well.” Below is a series of time-lapse movies and photographs as some pupated and emerged as adults:
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The phenograms show the maximum number of individual butterflies of this species seen in the first eight years of the Howard County Butterfly Survey. From these graphs, one can see the number of broods of each species, when they are active, and the relative abundance of the species in each brood. The observed early and late dates are shown below The graphs can be used to anticipate the first sighting of a given species in the year and can help with identification.
Early: 4/11/2017 Late: 10/28/2014