Harford County officials and Constellation Energy have shut down two well-loved trails around the Conowingo Dam after black vultures gathered near Fisherman’s Park tested positive for avian influenza. The Wildflower trailhead and a stretch of the Mason-Dixon Trail are closed indefinitely while crews remove carcasses and run lab tests.
Constellation told local media the move is meant to keep visitors a safe distance from dead birds after several black vultures produced positive H5N1 results, according to CBS Baltimore. Regulars at the dam, a go-to spot for eagle-watching, reported new warning signs and said the discovery was more than a little unsettling. Park users should expect tight restrictions near the Overlook parking area until officials give the all-clear.
Testing and agency response
Wildlife crews have been working the Wildflower and Mason-Dixon trailheads, collecting carcasses while laboratories conduct confirmatory testing, WMAR‑2 News reports. The Maryland Department of Agriculture is asking anyone who encounters a sick or dead bird to call 410‑841‑5700 for reporting instructions and guidance on disposal and testing, as outlined on the agency’s website. Nationwide surveillance from USDA‑APHIS shows detections of highly pathogenic avian influenza in wild birds are still popping up this spring, which officials say is a reason to stay cautious.
Not the first time here
These same trails were shut down in March 2025 after a similar cluster of dead vultures turned up in the area, as detailed in earlier Fisherman's Park trails closed coverage. Last year’s H5N1 wave killed millions of birds across the country, and this April the USDA logged roughly 220 confirmed wild-bird deaths tied to the virus, including 10 in Maryland, according to CBS Baltimore.
How to stay safe
Public health guidance stays straightforward: do not touch sick or dead wild birds, keep pets away from carcasses, and clean or disinfect footwear and clothing after visiting affected areas, according to the CDC. If you come across a dead or visibly ill bird, report it to state officials. The Maryland Department of Agriculture lists step-by-step reporting instructions and contact information on its website.
Constellation and its state partners say the trail closures will remain in place while testing and cleanup continue, and that sections will reopen only after officials determine the area is safe. Birders and anglers planning a trip to Conowingo are being urged to check for updates from Constellation and state agencies before heading out.
