Algae Bloom along coral reefs in West Maui, Hawaii

Ursula Keuper-Bennett howzit at
Mon Jun 18 07:56:57 EDT 2001

Dear Coral Reef and Algae researchers,

We're writing to make you aware of a major Cladophora algae bloom at our 
dive site in Maui --a main Hawaiian island.  Local papers have published 
several articles about the extent of this bloom.

The most recent appeared yesterday in the Maui News:


Two Oahu papers published algae-related articles about two weeks ago.  We 
offer them here as background information:



We're sharing this information because of its relevance to coral reefs, 
phycology and environmental degradation.

The papers report that columns of algae "stretch for miles from Kapalua to 
Black Rock in Kaanapali in west Maui."

Our dive site is dead centre of these two places.

Yesterday's Maui News article reads, "'It is in an uncontrolled state,' 
said Vickie Betts, resort manager with Kahana Village. The condominium 
project has hired two workers to keep the shoreline clear of the seaweed 
that began piling up on the shoreline from Napili to Honokowai at the 
beginning of May."

Honokowai is our dive site and the home of the turtles we write about on 
our webpage, Turtle Trax.

While the papers report this 2001 bloom to be the first since 1991, there 
were actually blooms in 1998, 99 and 2000 --each progressively worse than 
the other --with last summer's as bad as the original bloom of 1989.

This new 2001 bloom will make the fourth consecutive Cladophora bloom.  We 
suspect that like the past three summers, there will be a Lyngbya majuscula 
bloom as well.  (Lyngbya has a reputation for being toxic; Cladophora does 

Worse, the newspapers' descriptions lead us to anticipate this newest bloom 
will be on level with that of 1991.  If it IS as bad as 1991, the 2001 
bloom will be a killer for corals, unlike the previous three years.

We continue to sweep the Internet for news reports of algae blooms 
--especially blooms in green turtle foraging habitat.  Our own interests 
are in --but not limited to-- Cladophora and Lyngbya blooms.  For example, 
we know that Moreton Bay, Australia has experienced progressively worse 
annual Lyngbya blooms for several years now.  There appear to be annual 
Cladophora blooms sliming the water and littering the beaches in some part 
of the Florida west coast.

At Honokowai, these blooms coat conventional turtle forage --although he 
have no idea what effect if any this has on the turtles.

We're posting these mpgs because we want list members to see what we see 
underwater --the extent of these blooms--and view clips of turtles living 
in these conditions.   We hope this will be of particular interest to 
researchers working with blooms elsewhere.

(Note from 1988 through 1995 we did not use a filter on our camera so video 
appears blue-green)


Bloom on a strong current day and how it killed coral


Ursula sinking into the stuff --the sheer volume that collected between 
reefs.  There's nothing wrong with this footage --that's what conditions 
were like!



Typical of our green turtle pasture/residency site.  Here Lyngbya mixes 
with Cladophora coating extensive fields of Halimeda.


With the volume of Lyngbya came a "bloom" of sea hares (Stylocheilus) in 
the water column and yet many times more thousands littering the ocean 



Cladophora and Lyngbya bloom together again.


And effect on turtles?  Cladophora/Lyngbya snags a tumoured turtle.


This is our friend Polzbarney known since 1995 when he was an apparently 
healthy youngster.  Here in 1999 Cladophora trails from his eye tumours.


2000 --last summer:

Peter at a place we call The Graveyard because it's where the worst-case 
tumoured turtles prefer to hang out.


We have several "favourite" corals that survived the early 90's blooms and 
we've been helping them out during the last three bloom summers.  Cleaning 
algae from them has become part of our routine.  The trouble is they needed 
someone picking them clean all of this May and June.


And this was typical inshore --one to one-and-a-half meter depth.  Algae 
drifted and collected making navigating the shallows worst of all.


In those shallows are where the juvenile sea turtles feed daily...

And there's every indication 2001 will be worse than this.

If anyone knows of other tropical/semi-tropical areas blighted by repeated 
Cladophora and/or Lyngbya blooms we'd be interested in comparing 
notes.  Please feel free to pass this on to others who you think might find 
this of interest,  Or better yet --people who would be able to offer 
INSIGHT into what on EARTH is happening here.

And why it's happened four summers in a row.

Quotes from news story suggest these blooms are "natural".

Thank you for reading this far,
Ursula and Peter
               ^               Ursula Keuper-Bennett
              0 0              mailto: howzit at
     /V^\             /^V\
   /V     Turtle Trax     V\
  /                         \

"Men have forgotten this truth," said the fox. "But you
must not forget it. You become responsible, forever, for
what you have tamed."

           \       /     --The Fox shares his secret
           /  \ /  \       Antoine de Saint-Exupéry
          /__| V |__\
         malama na honu  

For directions on subscribing and unsubscribing to coral-list or the
digests, please visit, click on Popular on the
menu bar, then click on Coral-List Listserver.

More information about the Coral-list-old mailing list