Observation: Photinus pyralis

Observation: Photinus pyralis

Primary Observer:

Ed Chapman

Event Date:

2025-07-18

Status:

Verified

Survey

Site Name:

Rutgers University Somerset Street New Brunswick, NJ

Province/State:

New Jersey

Event Date:

2025-07-18

Time of Day:

Night-Time

Start Time:

20:15

End Time:

21:00

Number of Observers:

2

Primary Observer:

Ed Chapman

Additional Observers:

Norma Hoffman

Target Species Genus:

Photinus

Target Species Species:

pyralis

Location and Habitat

Location Accuracy (meters):

0-25

Habitat Type:

Developed - Sub/urban areas; parks/gardens

Habitat Type Notes:

Mature oaks, maples, evergreens; mowed lawn

Elevation (meters):

65

Area Searched (hectares):

1

Artificial Light Sources

Vehicles: Yes
Street Lights: Yes
Buildings: Yes

Artificial Light Types

Sky Glow (diffuse illumination in the sky): Yes
Light Trespass (light cast on surfaces beyond its intended target): Yes
Glare (bright light causing visual discomfort): No

Artificial Light Notes:

Post lighting, some security lighting, vehicles nearby but not through site.

Observation

Observation Type:

Flashing

Number Observed:

11-50

Genus:

Photinus

Species:

pyralis

Observation Notes:

30-50 males flying 3-6 feet scattered across the lawn; a few stationary females spotted.

Specimen Voucher Number:

Flash Behavior

First Flash Time:

20:15

Last Flash Time:

21:00

First Flash Temp (F):

75

Last Flash Temp (F):

75

Flashes in Pattern:

1

Flash Color:

Yellow

Flash Pattern Period:

6

Flash Duration:

1

Flash Interval:

5

Male Height Zone:

Moderate (3-8 ft)

Flash Location:

Scattered across mowed lawn under mature shade trees. Interestingly, as darkness progresses, they move more toward security lights.

Male Flash Behavior:

One flash, 5 second intervals, typical upswing J pattern.

Female Flash Behavior:

Females stationary, single flash, intermittent flash pattern.

1 thought on “Observation: Photinus pyralis”

  1. Thanks for submitting this firefly observation! Even without photos, this observation can be verified based on the characteristic flash pattern, and the urban setting also makes sense for Photinus pyralis.

    Interesting observation about the security lighting!

Leave a Comment

Connect

Sign up for our newsletter to receive updates.

Follow

Follow the Xerces Society.

Share

Share this page.

Support

Support the Xerces Society's conservation work.

This is a project of the Xerces Society, working in collaboration with the IUCN SSC Firefly Specialist Group and New Mexico BioPark Society.

Copyright © 2025 The Xerces Society •1631 NE Broadway Street, #821 • Portland OR 97232 USA