Two humpback whales swam in the Sacramento River on Tuesday (May 15) as concern grew over their welfare. Officials believe the mother whale and her calf got lost while migrating to Alaska and the mother is believed to be entangled in a fishing net. Humpbacks whales are an endangered species under U.S. law. The adult whales is approximately 45 feet long ( 14 meters) and her calf is approximately 17 feet (5.18 meters) long. The whales have traveled more than 50 miles (80 kilometers) from the Golden Gate bridge area of San Francisco. The Sacramento area had a whale sighting in 1985 when "Humphrey" the humpback whale captured curiosity before it was escorted back to sea.