WASHINGTON, Oct. 26 (UPI) -- Antarctic killer whales engaging in rapid migrations to warmer tropical waters may be seeking spa-like relief in the tropics, U.S. researchers say.
Scientists at the National Oceanographic and Atmospheric Administration said tagged Antarctic killer whales monitored by satellite traveled more than 5,000 miles to visit the warm waters off southern Brazil before returning immediately to Antarctica 42 days later.
This was the first long distance migration ever reported for killer whales, a release from NOAA's National Marine Fisheries Service said Wednesday.
"The whales are traveling so quickly, and in such a consistent track, that it is unlikely they are foraging for food or giving birth," NOAA researcher John Durban said. "We believe these movements are likely undertaken to help the whales regenerate skin tissue in a warmer environment with less heat loss."
A yellowish coating often observed on Antarctic killer whales -- caused by a thick accumulation of diatoms, or algae, on the outer skin of the animals -- is noticeably absent when they return from their warm-water trip Durban said.