The number of baby gray whales migrating along the U.S. Pacific Coast is increasing and scientists say it may be a sign of Arctic warming.

National Oceanic and Atmospheric Administration researchers counting the calves passing California's Point Piedras Blancas near San Luis Obispo tabulated 1,018 calves this year, up from 945 during 2005, The San Francisco Chronicle reported.

The agency reports an upward trend since the counts of 3-month-old, 20-foot-long whales plummeted to less than 300 during the years 2000 and 2001.

"In the short term, they appear to be doing well, based on our monitoring of reproduction, NOAA biologist Wayne Perryman told the Chronicle. "But we really don't know how the long-term warming trend is going to affect this population."

Global warming is beginning to affect the northern Bering Sea, the whale's traditional feeding ground, scientists say, noting the whale's favored prey, the fatty amphipod, is less abundant, sending the whales searching for food farther north.

Gray whales have fed in the northern Bering Sea for thousands of years.

Copyright 2006 by United Press International