Harbor Porpoises in San Francisco Bay Quiz

When did harbor porpoises begin returning to the San Francisco Bay after a 65-year absence?

• January 2012

• January 1972

• January 1940

• January 1950

What contributed to the poor water quality in the San Francisco Bay, driving away the porpoises?

• Shipbuilding industry

• Fishing industry

• Tourism industry

• Farming industry

What was the main reason for the porpoises' return in the 1970s?

• Improved food supply

• War activities ceased

• New shipbuilding techniques

• Increased tourism

What act led to an improvement in the water quality of the bay in 1972?

• Clean Water Act

• Marine Life Protection Act

• Environmental Safety Act

• Pollution Control Act

What species needed to return to the bay for the porpoises' food supply to recover?

• Herring and anchovies

• Salmon and tuna

• Sharks and dolphins

• Crabs and lobsters