Hale Kula ElementaryGrowing Sea Urchins

Problem-Invasive Seaweed( Smothering Seaweed and Gorilla Ogo )

• Invasive algae (Smothering Seaweed (Kappaphycus / Eucheuma), and Gorilla Ogo (Gracilaria salicornia) has been growing in Kaneohe Bay for more than 30 years. Many reefs throughout the bay are highly affected by their spread.

Possible Solution 1- Super Sucker• Good tool to collect invasive algae from Kaneohe Bay.• Collects about 2-8 thousand pounds of limu per day.• Given to farmers for composting.• However, in 5-6 months algae returns.

Possible Solution 2-Sea Urchins

• Sea urchins will eat invasive seaweed (Smothering Seaweed and Gorilla Ogo ) and help control its growth in the ocean.

Method 1-Growing Sea UrchinsFresh Water + Salt Water Powder

Water:- Mixture of freshwater and

instant ocean water mix.Sea urchin food:- Seaweed - Farm feed- NoriResults:- Many of the sea urchins in our

tanks did not survive, about 15-20 sea urchins were released in December 2012.

Students Taking Data

Method 2- Growing Sea UrchinsUsing Salt Water

Water:- Salt water was obtained

from a faucet in Sand Island.

Sea Urchin Food:- Only limu or ogo Results:- Higher percentage of

survival rate for our sea urchin.

Ocean Release of Sea UrchinsDecember 2012

Conclusions- Best way to grow Sea Urchins

• Avoid touching sea urchins regularly.

• Use ocean water to grow them in.

• Clean water filter and scrub aquarium weekly.