Windsurfers in California's Sacramento River Delta watched a humpback whale calf suddenly breach nearby. A mother and calf, straying far from their normal migratory route in the Pacific, swam far up the river in fresh water, triggering a multi-agency rescue operation. The whales swam back downriver after two weeks, passing ships, boats, and windsurfers on the way.
(Photo by Sarah Wilkin, NOAA)

The mother and calf humpbacks, nicknamed "Delta" and "Dawn", were wounded with gashes, without food, and in completely fresh water that degraded their skin. Their plight captured international interest and prompted the first successful injection of wild whales with antibiotics. Needles from the injection (visible in the larger whale) remain in place for hours before dropping out.
(Photo by Jamison Smith, NOAA)

For two weeks in May, mother and calf humpback whales veered into San Francisco Bay and swam through bays and past bridges of the Sacramento River Delta, ending up 90 miles inland at the Port of Sacramento before turning back downriver. The whales returned to the Pacific Ocean at night, and could no longer be monitored.
(Map by Jack Cook, Woods Hole Oceanographic Institution)