Fifteen pilot whales died in beach strandings Wednesday in southern New Zealand while rescuers refloated another 15 and monitored their progress toward safer waters, conservation officials said. The whales _ which ranged in size from calves to 6 meters (20 feet) in length _ were found beached at two locations on Farewell Spit on New Zealand's South Island, Conservation Department ranger Nigel Mountford said. Fifteen of the whales were dead when discovered. Rescuers helped refloat the remaining 15, but they were not out of danger yet because they remained in a tidal area where they risked beaching themselves again, Mountford said. A conservation worker was sent aboard a plane to monitor the bay for whales at risk of further stranding, he said. Department spokeswoman Trish Grant said the whales were last seen several kilometers (miles) from shore in eight meters (26 feet) of water, which was a good sign. «They were in fairly deep water ... so it's a good chance that they are just going to make their way back out to sea,» she said, «but nothing is certain.» Watchers were on duty in case the pod headed back toward the shore, Grant was quoted as saying by the Associated Press. Scientists are unable to explain why whales strand, but some believe it is caused by disorientation in their sonar sounding systems. New Zealand has several mass strandings each summer, with Conservation Department records showing more than 5,000 whale and dolphin strandings since 1840. In January 2006, 178 pilot whales stranded in the Farewell Spit area, a broad expanse of sandy bar at the northwest tip of the Golden Bay region, about 100 kilometers (60 miles) from the city of Nelson. Twenty-nine died.
