This map was created for a National Geographic Daily News article and illustrates how blue whales frequent waters that overlap with some of the busiest commercial shipping lanes. Scientists tagged blue whales and monitored their movements between 1993 and 2008, proving that blue whales spend their summer months in the shallow waters surrounding the Farallon Islands and Channel Islands, both off the coast of California. Unfortunately, shipping lanes run through these "hot spots" and often result in fatal ship strikes. A special thanks to Ladd Irvine of Oregon State University for providing the data.

*Data exclude values less than six.

Credit: NG Staff, Jamie Hawk. Sources: Ladd Irvine, Oregon State University; USGS