A shark was spotted unusually far from home on Monday, having ventured from the ocean into a body of water further inland.
The shark was spotted in Lake Merritt, a tidal lagoon in Oakland, California.
As reported by KTVU FOX 2, the leopard shark had made its way into the lake from San Francisco Bay, which while bizarre, is not the first time marine animals have explored the lagoon waters.
In 2020, local news website The Oaklandside reported that a variety of ocean-dwellers had been spotted in the lake, including sea lions, bat rays, salmon, sturgeon, jellyfish and other leopard sharks.
Leopard sharks are one of the most common sharks along the coast of California. They can be found along the west coast between Oregon to Mazatlán in Mexico. These spotted sharks can grow to around 7 feet long, and spend the majority of their time feeding close to the sea floor in kelp forests, eating small seabed creatures including most significantly crabs, shrimp, bony fish, fish eggs, clams, and a variety of marine worms. The sharks usually don’t swim deeper than around 65 feet below the surface, but have been found up to 300 feet deep on occasion.
Leopard sharks are harmless to humans, with the Florida Museum’s International Shark Attack File only noting one incident where a human was injured by a leopard shark, where a diver with a nosebleed in 1955 was harassed by one of the sharks. These sharks are often deliberately fished for their meat. However, the California Department of Fish and Wildlife warns against eating them regularly due to the high levels of mercury and other pollutants including pesticides, and polychlorinated biphenyls (PCBs) inside their bodies.
Lake Merritt formed around 10,000 years ago, after rising sea levels due to the end of the last Ice Age flooded inland, creating the lagoon. The waters in the lake are brackish, due to being comprised of a mixture of saltwater from the sea and freshwater from natural rivers flowing from inland.
The animals spotted in the lagoon usually venture via the Lake Merritt Channel.
Lake Merritt was designated the first official wildlife refuge in the U.S. in 1870, but has struggled with poor water quality and plastic pollution in the 150 years since. However, the local community is dedicated to cleaning up the waters, with between 1,000 and 6,000 pounds of trash being removed monthly since 1996.
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