The stench of rotting fish is filling Washington's National Mall during the height of the summer tourist season, placing the Park Service's aging infrastructure and poor ecological design in full view.
The region's heatwave is partly to blame for the hundreds of fish going belly-up on the surface of the Mall's centrally located Constitution Gardens pond near such popular attractions as the Washington Monument and World War II Memorial, the Washington Post reported Wednesday.
National Park Service agents have been scrambling to remove the carcasses of dead bluegill, sunfish and other common species from the pond, while noting that the pungent smell of rotting fish has been lingering in the air for days.
Park spokesman Mike Litterst told the newspaper that "there was still an odor in the air." Nevertheless, such a large fish kill is "not a rare occurrence," he said, especially in light of Washington's hot and extremely humid summer weather. Temperatures have been higher than 90 degrees for eight straight days.
He said the last time a fish kill occurred was in 2013.
The pond's shallowness makes it heat up and lose oxygen fast, suffocating the fish. But heat is only part of the problem. The other problem is the pond's poor ecological design, Litterst said.
The "poor design and construction" makes for "a closed system, which makes maintaining an ecological balance difficult," he said. When combined with the high temperatures, it causes algae blooms that further rob the fish of life-sustaining oxygen.
Park officials said they have longer-term plans to update Constitution Gardens with improvements that would make it "a better ecological environment," the Post reported.