DIFFICULT RUN ABOVE FOX LAKE NEAR FAIRFAX, VA

DIFFICULT RUN VA USGS

DIFFICULT RUN ABOVE FOX LAKE NEAR FAIRFAX, VA (01645704) is a real-time streamflow monitoring station on the DIFFICULT RUN in VA, operated by the U.S. Geological Survey. Riverbot tracks its streamflow and alerts anglers the moment flow and temperature hit their fishing window. 27 fish species are associated with this station in public fish records.

USGS site number: 01645704
Agency: USGS
State: VA
Coordinates: 38.8847, -77.3324

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Fish recorded near this station

Community observations nearby

Difficult Run Above Fox Lake Near Fairfax, VA has 27 fish species documented via iNaturalist research-grade observations within 10 km. These community-sourced records indicate fish presence in the vicinity.

Species include: Yellow Bullhead (Ameiurus natalis), American Eel (Anguilla rostrata), White Sucker (Catostomus commersonii), Rosyside Dace (Clinostomus funduloides), Grass Carp (Ctenopharyngodon idella), and 22 others.

Yellow Bullhead Ameiurus natalis
American Eel Anguilla rostrata
White Sucker Catostomus commersonii
Rosyside Dace Clinostomus funduloides
Grass Carp Ctenopharyngodon idella non-native
European Carp Cyprinus carpio non-native
Amur Carp Cyprinus rubrofuscus
Northern Tessellated Darter Etheostoma olmstedi
Eastern Mosquitofish Gambusia holbrooki
Common Sunfishes Lepomis
Redbreast Sunfish Lepomis auritus
Green Sunfish Lepomis cyanellus
Green Sunfish × Warmouth Lepomis cyanellus × gulosus
Warmouth Lepomis gulosus
Bluegill Lepomis macrochirus
Greengill Sunfish Lepomis macrochirus × cyanellus
Bluegill × Redear Sunfish Lepomis macrochirus × microlophus
Redear Sunfish Lepomis microlophus
Largemouth Bass Micropterus nigricans
Swallowtail Shiner Miniellus procne
Golden Shiner Notemigonus crysoleucas
Rainbow Trout Oncorhynchus mykiss
Black Crappie Pomoxis nigromaculatus
Flathead Catfish Pylodictis olivaris
Eastern Blacknose Dace Rhinichthys atratulus
Creek Chub Semotilus atromaculatus
Fallfish Semotilus corporalis

2 species above are flagged non-native or potentially invasive (Grass Carp, European Carp). Records show what has been observed near this station, not what is native to the watershed.

Where these records come from

Evidence: Community observations nearby; Research-grade community observations (iNaturalist) recorded near this station, not a formal survey.
Records: 27 species; from 200 individual records
Observed: Sep 6, 2025 – Jul 21, 2026; 200 dated records

Sources

iNaturalist research-grade fish observations — 200 records