Thursday, September 17, 2020

Learn about the Crown-of-Thorns Star

The crown of thorn Starfish are found on nearly every site we visit on the Kohala Coast. Divers often ask us after a dive "What was that cactus looking thing" or "was that a weed on the coral?" Read on for some info on these interesting invertebrates. 

By  Dominic S. Romer

Dive Master

While enjoying the reefs of Hawaii and all their marine life, spare a thought

for the corals on today’s menu!

The diner is Acanthaster planci , Crown-of-Thorns star (COTS) and his

favorite meal is coral polyps, especially those of Pocillopora meandrina

(Cauliflower coral).

The body is disc-shaped, up to 18” across, with as many as 21 arms, it’s

usually red/green in color and the whole thing is covered in venomous

spines. Don’t get too close...many divers will tell you of their discomfort

having inadvertently got too friendly with this star (burning pain, numbness

and possible discoloration of the area for a couple of days)!

They are impressive creatures, using all of those arms to climb atop coral

colonies where they then extrude their stomachs and secrete enzymes to

liquify & digest individual coral polyps. Just the white coral skeletons

remain, when they absorb the available nutrients and move on. True horror

movie stuff!

While these stars have wreaked havoc on some reefs around the world

(including the Great Barrier reef), here in Hawaii we don’t appear to have a

big issue with them yet and usually, one won’t see more than a few at any

one site. In places where they have become a real issue, divers can

physically remove the creatures or inject them with household vinegar to kill

them...although either option is time consuming & costly.

There are some in Hawaii who believe that this predator may in fact be

doing some good for the reef, feeding on some of the faster growing corals

(such as Cauliflower & Rice corals) and increasing coral diversity on

Hawaiian reefs.

In Hawaii, their main natural predator is the Triton’s Trumpet snail; also

Harlequin Shrimp, Stripebelly Pufferfish and Lined Fireworms will feast on

this star.

We hope you will get a chance to observe this impressive star, when diving

with us at Kohala Divers in Hawaii!

Wednesday, May 20, 2020

Divers Who Defog: Your Glasses!

Is this you?!?! Do you exhale in your socially-distant mask and fog your glasses? Well, the people who de-fog your scuba mask have some advice:

1) Start with a clean pair of glasses. This goes for your scuba mask, too! Use your dish soap: It is a fabulous de-greaser! Clean both inside and outside lenses, nose-piece, ear wands... all of it. Leave to dry or dry with a soft micro-fiber cloth.

2) A close fitting nose piece on your mask will reduce the fog exiting the top of the mask onto your glasses. Re-bend your nose wire (if it has), use a buff, situate it a little lower on your nose bridge (but still wear it properly! Cover those nostrils!)

3) When I know I will spend all day in glasses/mask combo, I clean my glasses that morning!

4) Our goggle/eyewear defog spray is made for this purpose: Spray both sides and clean dry with a cloth. DO NOT USE concentrated scuba defog, meant to be used with water! Check the print on your defog: Goggle defog is already watered down for use that close to the eyeball.

5) Hey! While you are at it, get your scuba mask out and give it a clean! Use that same dish soap! Then allow to dry and store in it's box. If you have a neoprene mask strap, remove it from the mask while in storage: Neoprene off-gasses and discolors silicone mask skirts. We will be back using that spotless and non-discolored scuba mask in no time at all! Promise!