Missing Humpback Whales

File - In this March 21, 2012 file photo, a humpback whale dives near Starrigavan estuary in Sitka, Alaska. Over the past several years researchers have noticed a decline in the number of North Pacific humpback whales showing up in their traditional breeding grounds around Hawaii. The missing humpbacks migrate each autumn from Alaska, where they feed during the summer months, to Hawaii, where they mate and give birth during the winter. (James Poulson/Daily Sitka Sentinel via AP, file)