Area of Focus: Marine Mammals

Ship noise interferes with the ultrasonic echolocation the marine mammals use to catch fish

Numbers have declined a small amount despite increase in harvesting in some areas

Researchers worry it’s an “early warning sign” that the population is in jeopardy

The species was one of 12 whose statuses were being reconsidered

Researchers combined sounds from the sea with views from the air

The population is down to only 73 reproductive females

An anchovy boom has brought vast numbers to Fisherman’s Wharf

Researchers tested computer programs to see how well they identified individuals by their markings

Resident and transient killer whales overlap but don’t mix

Scientists believe the mammals are contracting the virus from affected seabirds