Tag Archives: cobia

Summer Term 2013: Student Update July 6, 2013

Orientation Week continues with kayak and SCUBA!

P7050849
K4 prepares for their daylong kayak trip.

The kayak trip was a great experience for all Island School students.  We learned the basic kayak skills, such as what to do in a situation when the kayak tips over.  The current was both with and against us at different points during the trip.  We traveled from campus to Triangle Cut then through the Marina to Sunset Beach.  At Sunset Beach, we began a lesson about the moon phases and how the position of the moon affects the tides.  We enjoyed a short snorkel and swim at the beach.  For lunch, we ate awesome PB&J tortilla wraps with great GORP (Good Old Raisins and Peanuts) on the side.

After lunch, we got back in our kayaks and made our way to No Name Harbor, where we explorP7050840ed the mangroves while fighting the current which tried to push us to shore!  The wind began pushing us back to campus as we started our travel in our kayaks. Although we were tired and sore by the time we got back, it was a great day on the water.  We finished up our kayak day by washing the kayaks and lifting them back under the boat house and we were free to explore the Cape for exploration time!

In addition to kayaking on the surface of the water and exploring the island on vans on the South Eleuthera Road Trip (SERT) this week, we began to develop a sense of place for South Eleuthera through SCUBA diving!

“We are ok!” Student’s head out to dive on the Cobia.
“We are ok!” Student’s head out to dive on the Cobia.

We took our first breath underwater and plunged deeper and deeper into the ocean.  In order to be certified divers, most of us had to develop skills such as buddy breathing, buoyancy, and other basic skills.   In addition to these requirements for certification, we had a great time taking in our surroundings.  A couple of ways that we made the dives fun were break dancing in the water and doing handstands.  While underwater, we also had the opportunity to see some really cool marine life such as: sting rays, battle stars, and many colorful fish.

Students on Boys Dorm Beach for the 4th of July bonfire.
Students on Boys Dorm Beach for the 4th of July bonfire.

Even though our orientation week has been really busy, we are learning a lot about where we are and we even found time to unwind on the Fourth of July to celebrate America’s independence. We roasted marshmallows on the bonfire and we made s’mores (which for some of us was a first!) out on Boys Dorm Beach. We laughed and sang songs that reminded us of home. We realized how close we had become in only a few days!  We lit sparklers and hung out all together.  We are getting even more excited for the Bahamian Independence Day celebration tonight in Governor’s Harbour!

Thanks to Taylor, Tim, Sophie, and Sydney for this Student Update!
Thanks to Taylor, Tim, Sophie, and Sydney for this Student Update!

 

 

Cleaning the Aquaculture Cage

As another piece of the Food week curriculum, students dive the offshore aquaculture cage. The SeaStation is a 3000 cubic meter cage, presently housing roughly 1000 cobia. The following photos were taken last week when the students visited the cage and spent the afternoon cleaning the netting and learning about aquaculture in The Bahamas. Check them out!

[slideshow]

Cobia Moved to the Aquaculture Cage!

The aquaculture program here is running essentially a model system for the commercial aquaculture industry; we aim to display that (delicious) carnivorous fish, cobia in our case, can be farmed in the Bahamas in an ecologically and economically sustainable fashion. Just last week we moved all of the juvenile cobia (around 1,000 fish) from the wet lab into the cage, which was quite an impressive feat. I don’t know why little fish would fight going into a huge shark resistant cage in the ocean to be fed every day, but fight they did. Though, with the help of pretty much the entire staff here at CEI the process went very smoothly. While one team transferred the cobia to two 1,400 L (~400 gal) totes to be anesthetized with clove oil, another team prepared another two totes onboard the aptly named research vessel, the Cobia, and waited at the marina down the road. The initial two totes were driven over, and the fish were transferred with nets to the totes on the Cobia. Some of the fish didn’t feel like consuming the clove oil and being calm apparently, so this part was very slippery and prickly (cobia have spines) for us humans. All the fish were moved safely though, and we drove the boat out to the cage.

In order to put the fish in the submerged SeaStation cage, we crafted a “toilet” of sorts: a bucket with Continue reading

More Baby Fish Have Arrived!

On Friday, January 27th half a million eggs arrived from Miami, Florida! They were placed in an incubation tank, where they hatched early Saturday morning. To the naked eye they looked like pieces of rosemary floating in the water. But under the microscope you could see the egg sack that was encased around the head and the tail was sticking out. The bottom of the tank was siphoned in order to get rid of the unhatched eggs and dead larvae. This is very important because if they were left in the tank bacteria can grow, which can kill the larvae. After determining how many larvae were alive, they were then transferred into six larval rearing tanks. They will obtain their food from their egg sack for three days. Cobia develop after they hatch, which means their mouths are very small and in turn can only eat rotifers for the first couple of weeks. They will eat enriched rotifers for about three weeks and then move onto eating artemia for another 45 days. Once they start growing more we will be able to wean them onto dry food and then eventually bring them out to the offshore cage that is fitted with shark resistant netting that was donated by DSM Dyneema!

[slideshow]

The Fish Have Arrived!

I repeat…THE FISH HAVE ARRIVED!

[slideshow]

After much anticipation, we got the call! The cobia fingerlings had a long journey from The University of Miami’s experimental fish hatchery at RSMAS to the Cape Eleuthera Institute. We spent the day preparing the tanks for the fingerlings…scrub, rinse, soak, drain, scrub, rinse, fill! Marie and Josh took the truck to pick up the 13 boxes from the Rock Sound Airport Friday afternoon. It was like Christmas morning when the truck finally pulled up. We put the bags in the tank to acclimate the cobia to their new home. After, we opened each bag and carefully let them free! The fingerlings will be used in an upcoming feed trial. Continue reading

Aquaculture Research Class

[slideshow]Digging my fingers into the dog food like fish meal, I grabbed a handful and tossed it into the large tank filled with ravenous cobia. This is one moment that we experienced during our introductory day to the world of aquaculture. Many people don’t fully understand how aquaculture works or even simply what it is. Aquaculture, otherwise known as fish farming, is the cultivation of aquatic plants and animals, and is often perceived as a sustainable practice. However, people do not realize the negative repercussions that it has. To sustain the farmed carnivorous fish, smaller pelagic fish must be harvested to create fish meal. Our goal through this project is to determine if we can use a smaller percent of fish meal in the feed and still produce an equal amount of growth.

Last semester a group students compared the growth of fish using 40% fish meal feed and 80% fish meal feed and found that there was no difference in the rate of growth. This summer we are comparing the growth of fish using 25% fish meal to 40% fish meal. We are predicting that the fish fed 25% fish meal and the fish fed 40% fish meal will grow at the same rate. If our data supports our hypothesis, then aquaculture can become a more sustainable industry. Currently we are testing 3 tanks filled with cobia, 2 of which are fed 40% fish meal and the other 25% fish meal. One problem we face with the cobia in close proximity is the transmission of parasites.

One method used to remove parasites is formalin, a chemical that can cause excessive damage to not only ourselves but the environment around us. A new method that has been recently proposed is the use of gobies, which are cleaner fish. Another thing we would like to study in this term is the use of formalin compared to the use of gobies to remove parasites. We hypothesized that sadly the formalin will be a more effective parasite removal method. This is because the gobies have too many variables that we are unable to control, such as the cobia may eat them.

We have already learned much about the sustainability and misconceptions of fish farming. We hope that we can find ways to make aquaculture a more sustainable industry for the future! Working in the lab is always a fun and interesting part of our day and we cannot wait for the results of our experiment.

Fish Silage: Turning Fish into Fertilizer

Island School students, Aldis, Brett, and Sara are doing a human ecology project that utilizes the cobia harvesting waste into livestock feed and fertilizer, trying to further close the loop in our sustainable model here at CEI/IS.  The fish silage will be used to feed the pigs and tilapia, as well as a fertilizer at the farm. Continue reading

Cobia for Parents Weekend Dinner

The Island School parents arrived for the weekend’s festivities full of excitement and overjoyed to see their children and their life for the past 3 months.

After 7 months of raising cobia, CEI’s aquaculture program decided to conduct the first harvest of 2011, just in time for parents weekend. A total of  150 cobia were harvested and filleted by CEI staff and IS students Brett, Sara, and Aldis. All fillets were prepared on the grill by Geoff and our lovely kitchen staff.  The grilled cobia fillets were presented at dinner and cobia ceviche as an art show appetizer wednesday evening.  After so much hard work and various obstacles, the aquaculturalist’s at CEI were overwhelmed with joy and tasted the success of cobia at dinner!  There is more to come!

Where does all the cobia carcass waste go?  

Stay tuned for our next update… “Fish Silage”

It is official, Gobies clean brood stock cobia!

What an exciting Monday morning for aquaculture! We now have 3 goby breeding pairs that have all laid eggs this week. Our most recent pair needed to be separated from the two other resident gobies, so we decided to experiment. It has been relayed by word of mouth that gobies will clean parasites off the cobia. Nothing is ever that easy at CEI, so we needed to see it to believe it.

Nine thirty this morning, Marie and I decided to take the leap of faith and place the 2 gobies into the brood stock cobia tank. No one knew what to expect. Would the gobies like their new home? Would the cobia know to stay still so the gobies could clean them? How long would it take until we would observe the gobies actually cleaning the cobia?

Continue reading

Harvesting Cobia with the Aquaculture Research Team

Eliza shows off her filleting skills

Today we strayed from our usual “water parameter, goby feeding” routine and went diving into the offshore cage. We loaded nets, bags, and scuba gear into Red Rising. Sitting on the bow of the boat, we looked at the aquaculture cage 50 feet down in the water. Snappers, grouper, cobia, and even two bull sharks circled the cage. Then, we began our decent. As we approached Continue reading