(Seattle, WA)  --  A Puget Sound southern resident orca is missing and presumed dead.  The Center for Whale Research says the 23-year-old male orca named L-92 has been missing for about a month.  The organization says the loss of the whale brings the southern resident orca population down to just 75.  The entire Puget Sound orca population is currently sitting at a 30-year low.