Observation: Photinus pyralis
Primary Observer:
Lisa Zimmerman
Event Date:
2026-07-15
Status:
Unreviewed
Survey
Site Name:
Kelly’s Run Site 3
Province/State:
Pennsylvania
Event Date:
2026-07-15
Time of Day:
Night-Time
Start Time:
20:30
End Time:
21:50
Number of Observers:
2
Primary Observer:
Lisa Zimmerman
Additional Observers:
Mara Zimmerman
target_species_genus:
unknown
target_species_species:
unknown
Location and Habitat
Location Accuracy (meters):
25-50
Habitat Type:
Woodland/Forest - Trees dominant, and in the over-story
Habitat Type Notes:
Some sections of the forest had small clearings filled with invasive grassy plants.
Elevation (meters):
218.4
Area Searched (hectares):
74.83
Artificial Light Sources
Vehicles: No
Street Lights: No
Buildings: No
Street Lights: No
Buildings: No
Artificial Light Types
Sky Glow (diffuse illumination in the sky): Yes
Light Trespass (light cast on surfaces beyond its intended target): No
Glare (bright light causing visual discomfort): No
Light Trespass (light cast on surfaces beyond its intended target): No
Glare (bright light causing visual discomfort): No
Artificial Light Notes:
Observation
Observation Type:
With Flash Data
Number Observed:
11-50
genus:
photinus
Species:
pyralis
Observation Notes:
These fireflies were mostly observed at the forest edge as we first hiked into the forest and in the more invasive grass clearings within the forest. However a smaller number of this species flashed in the dense forest locations. The caught specimen was 1.4 cm long.
Specimen Voucher Number:
Flash Behavior
First Flash Time:
20:30
Last Flash Time:
21:15
First Flash Temp (F):
86.9
Last Flash Temp (F):
87.4
Flashes in Pattern:
1
Flash Color:
Yellow
Flash Pattern Period:
3.68
Flash Duration:
0.36
Flash Interval:
3.32
Male Height Zone:
Low (0-3 ft), Moderate (3-8 ft)
Flash Location:
These fireflies flashed above short shrubs and grasses at the beginning of the night but then rose higher into the lower tree canopy as the night progressed.
Male Flash Behavior:
The males had a longer flash pattern and flew in an upward j-shape while flashing.
