Ho'okena and Beach 69. The Best of the North and South.

   This last week Sandra and I splurged with two wonderful outings.  Early in the week we went to Ho'okena and on Friday we shot up to Beach 69.

Bluefin Trevally Hunting with a Whitemouth Moray

    Although it appeared cloudy as we drove south, by the time we got to Ho'okena the day was clear and bright and the the swell was gentle.  Even more amazing for this time of year, the water was crystal clear.  Varying from our usual plan of attack, about twenty yards out we turned north, parallel to the shore.

    Not too far along, in about twenty feet we saw a whitemouth moray hunting, accompanied by a pair of bluefin trevally.  We were able to watch this interaction for about five minutes, as the whitemouth worked his way from one coral head to the next.  The trevally swam, at times, very close to the head of this large eel.  At least twice the eel reacted in a threatening manner, indicating that he was getting precious little from the association. 

The Whitemouth Moray Threatens the Bluefin Trevally

   About a year ago, one of our readers chided me for not including the eel and ulua in my list of commonly observed symbiotic relationships on the reef.  This association is not nearly as common as the blue goatfish and the ulua.  If octopus was more common here in Kona, I am sure we would see the multiband goatfish and the day octopus teaming up more often, as well.  (As it is, I see a day octopus hunting so seldom that I have not seen one working with a goatfish in a very long time. Mostly when I see an octopus he is diving for cover, the better to avoid Da Poke Shack!)  I'm not sure that I have had as good a look at the eel-ulua relationship before and armed with this new information, I'm fairly sure that I would not call it mutualism, where both species benefit.  The goatfish readily accepts the company of one or two bluefin trevally and the octopus clearly works cooperatively with the goatfish.  This eel did not appear to be getting anything in return.  One does not usually think of a tuna as a parasite, but it appeared that the ulua was gaining something at the expense of the eel.  (According to wikipedia, if the trevally benefits and the effect on the eel is neutral, we should term it commensal.)

     Leaving the eel and ulua to work out their differences without Sandra, who is widely known among the fishes as the "Madeleine Albright of the Reef", we headed for the deeper portion at the terminal footing of the

 Mu Monotaxis grandoculus, juvenile, Ho'okena Sept 2014

defunct landing.  There, between the old pier and the adjacent coral pillar, we saw a bay Mu.  (I can not resist telling you that in bovine cirles the Baby Mu is referred to as a calf.)  The water was clear and we had a fine look at this young grandoculus.  Unlike his elders, who ply the waters of the upper column, the calf never left the bottom thirty feet below.   The water was perfectly clear, so, with my modest diving skills, I was able to get a picture.  But it would have been a better photo had I been able to dive closer.  It should be noted that this calf was every bit as circumspect as his elders,  moving away when I dove for a better shot.  When I see my friend the Mu on the reef, he generally does not allow a close approach, the better to avoid the aforementioned Poke Shack.  So its not clear that, even if I was able to plunge 50 feet like our friend Bob Hillis, that I would have been afforded a better shot.  I hope you enjoy the goldeheaded photo that we did get.

     This brings to a conclusion the first installment of Ho'okena and Beach 69.  Before going my editor wants

 us to throw out a “ Herzlichen Glückwunsch zum Geburtstag.” to Doctor Don, her cousin from New Hampsire, who is a devoted reader of the Kona Beach Blog.  Doctor D has contributed the accompanying photo of a species, the Sockeye Spamon, that he caught spawning while snorkeling in the Back Bay down in Boston.

   So everyone raise a glass and wish the Doctor a Happy Birthday!

jeff