T he annual Fourth of July fireworks show on the San Francisco waterfront started at about 9:30 p.m. on Friday. The fireworks were launched from two barges on San Francisco Bay, one located at Pier 39 and another located at Aquatic Park. The show went on for about 30 minutes.

"Disturbing roosting migratory birds at night can result in mass deaths," says Bateman. "Disturbing breeding birds can result in colony collapses. Seals and sea lions leave [affected] areas and expend energy swimming away during fireworks."

Friday marks the 249 th anniversary of the adoption of the Declaration of Independence — and the Fourth of July holiday has become one filled with fireworks, musical celebrations and other flag-waving opportunities.

As Americans celebrate Independence Day with fireworks and parades, many businesses and services will alter their hours or close altogether for the Fourth of July. As is standard practice, U.S. stock markets will be closed on Friday in observance of Independence Day.