Marine officials don't want a repeat of Thursday's tragic scene involving a whale and a cargo ship.
In an attempt to protect whales traveling in and around the Golden Gate, marine sanctuary officials are asking boaters and vessel operators to take extra care when navigating the waters off San Francisco.
Large whales swim along the North-Central California coast year-round, but the whales are showing up in numbers now to feed on krill -- tiny shrimp-like crustaceans that are in abundance this time of year, according to Gulf of the Farallones Marine Sanctuary officials.
Many of these whales travel directly through the busy shipping lanes off San Francisco because they migrate to the sanctuary located just beyond the Golden Gate.
Thousands of ships and smaller vessels pass through the Golden Gate each year. At times, the whales are so distracted by eating that they fail to evade oncoming boats, sanctuary officials said.
Whales are especially vulnerable around fast-moving boats because of the threat of being sucked up into the ship's hull and propeller.
Collisions with the animals, which are protected by the Marine Mammal Protection Act, can have disastrous results for both the whales and boats, no matter how large or small.
Boaters are advised to keep a minimum distance of 100 yards from any whale. Additionally, boaters should avoid cutting across a whale's path, making sudden speed or directional changes, or separating a whale cow from her calf, which would likely die of starvation, officials said.
Some local species, such as humpback and blue whales, are also considered endangered and are shielded under the Endangered Species Act.