Observation: Photuris forresti

Observation: Photuris forresti

Primary Observer:

Richard Joyce

Event Date:

2022-06-01

Status:

Verified

Survey

Site Name:

Harris Shoals Park, Watkinsville

Province/State:

Georgia

Event Date:

2022-06-01

Time of Day:

Night-Time

Start Time:

20:45

End Time:

22:50

Number of Observers:

3

Primary Observer:

Richard Joyce

Additional Observers:

Gordon Ward, Rob Tiffin

Target Species Genus:

Photuris

Target Species Species:

forresti

Location and Habitat

Location Accuracy (meters):

25-50

Habitat Type:

Open Freshwater Wetland - Wetland Bog, fen, freshwater marsh

Habitat Type Notes:

Shrubby marsh upstream from a dam on Call's Creek. Flora include alder, red maple, arrow arum, and jewelweed.

Elevation (meters):

200

Area Searched (hectares):

0.5

Artificial Light Sources

Vehicles: No
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): Yes

Artificial Light Notes:

Only skyglow in wetland interior. Trespass and glare from houses and streetlights at the edges.

Observation

Observation Type:

Flashing

Number Observed:

11-50

Genus:

Photuris

Species:

forresti

Observation Notes:

Captured male estimated to be 12-13 mm long (using 5 mm gridded paper).

Specimen Voucher Number:

Flash Behavior

First Flash Time:

21:20

Last Flash Time:

22:37

First Flash Temp (F):

77

Last Flash Temp (F):

77

Flashes in Pattern:

>4

Flash Color:

Green

Flash Pattern Period:

Longer than could be easily measured (>20 sec)

Flash Duration:

0.4 seconds

Flash Interval:

0.6

Male Height Zone:

Low (0-3 ft), Moderate (3-8 ft)

Flash Location:

Male flashes were above the wetland vegetation, especially in the slightly more open area downstream from the middle of the boardwalk. Flashes of presumed females were from foliage of vegetation (including willows) at heights of 2-8 feet. Voice recordings used to estimate flash intervals, and flash durations estimated based on flash intervals.

Male Flash Behavior:

Vertical up-and-down flash-trains with 5-7 flashes. Estimated "around a dozen" males displaying around the boardwalk.

Female Flash Behavior:

Female Photuris observed flashing erratically from vegetation, but these flashes were presumably not flash responses to male displays.

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