Whether the sighting of a hammerhead shark on Tuesday off Dana Point–the second in a week–has anything to do with a developing El Niño is debatable.
But both were unusual, if not rare sightings, and some are speculating that unusually warm surface temperatures off Southern California are a factor.
The 6-foot hammerhead was spotted by passengers on a whale-watching trip with Captain Dave’s Dolphin & Whale Safari , which runs from Dana Point Harbor. (Be sure to watch the video in HD.)
[youtube https://www.youtube.com/watch?v=fqv6F1ImQfY?feature=player_detailpage]
Hammerhead sharks, which can measure 15-plus feet and reach weights of about 1,000 pounds, are so-named because of the odd shape of their heads, which they sometimes use to pin prey, such as stingrays, to the sea floor.
They reside in tropical and temperate seas around the world, but seem to show off Southern California during warm-water events. Sightings were made locally during the past two strong El Niño, in 1982-83, and 1997-98.
Surface temperatures off Southern California are ranging from about 71 to 75 degrees, 2-3 degrees above normal in some areas for this time of year.
Because the water is so warm, some exotic species of fish are beginning to show in local waters.
These include yellowfin tuna– a small yellowfin was captured recently in Newport Harbor –and needlefish.
As for El Niño, which is born as a result of abnormally warm water in the equatorial Pacific, NOAA will release its next forecast on Thursday.
The last forecast , issued June 5, stated that there’s a 70% chance of El Niño becoming a reality during the Northern Hemisphere summer, and an 80% chance during the fall and winter.
–Pete Thomas
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