Thursday, July 28, 2011 –
Our connections in Angra dos Reis with the IED-BIG/ Projeto POMAR's are great. This aquaculture education/ environmental restoration project has been supported by Petrobras (Brazilian state oil company) for 17 years now, mostly under the supervision of our friend Dr. Luiz Zaganelli, who has hosted UA Dallas students and teachers for 3 consecutive years now.
Initially, the baby scallops settle down in Netlon® netting. (see blue and green netting on right side of below image.) As they grow, they are transferred to ‘lanterns’ which may vary in mesh size and holding capacity, from a few millimeters and several thousand individuals per level of the lantern to finally a large gauge netting holding only 2 dozen scallops in a 6 tier lantern such as held by Emily (see far left of the below image).
These lanterns, of course, must be periodically cleansed of marine ‘fouling’ i.e. several other (undesired) species of marine organisms willing to settle and grow on the lantern surfaces, thus reducing the free flow of water and food supply for the baby scallops.
During their 2 weeks in the POMAR lab, scallop babies are fed a diet consisting of up to 10 different species of marine microscopic algae, furnished sequentially as a function of the baby scallops capacity to ingest different sizes of phytoplankton, and their changing dietary requirements.
Whereas scallop farming and scallop stock enhancement are the primary goals of POMAR, a new line of use for this important mollusk is being examined – its potential as a bioindicator of environmental quality around petroleum production and research operating equipment. Thus, adult individuals are placed in cages around oil rigs and platforms to be later recovered and examined for evidence of environmental quality history.
Finally, we are thankful to Dr Zaganelli not only for giving us a complete tour of the site, but also for inviting UA Dallas students to come in the future as scientific trainees. In the past he has received students from the US, Cuba, Germany and Venezuela which have collaborated in the production and also managed to collect and compile data which have been used in several theses. He would be happy to have any of our promising group of young scientists!
Nodipecten nodosus, is the scientific name of the local species of sea scallop. It is an endangered species, still recovering in numbers but under special protection status. To assist in this environmental restoration, the POMAR Project produces between 3 - 12 million scallop 'spat' per year. Part of these very young scallops are released in sheltered areas of the Ilha Grande bay where they can then grow and enhance local stocks, allowing the fishery to fully recover. Another part of the lab production is distributed among shellfish farmers - aquaculturists.
The 'baby' scallops are born as free swimming planktonic larvae by the millions… However, in the open sea, they are mostly devoured by other marine organisms low in the food chain… At POMAR, Nodipecten ‘babies’ are artificially mass produced and reared under the protected conditions of the lab environment for at least 12 days. They then settle down on rigid surfaces provided for them. Passing through a metamorphosis they grow in their adult ‘benthic’ form, looking much more like their parents, as a little two-valve mollusk! We had a peek at some 11 day old planktonic babies, under the microscope just a day before they should be ‘settling’ down for their adult life.
The 'baby' scallops are born as free swimming planktonic larvae by the millions… However, in the open sea, they are mostly devoured by other marine organisms low in the food chain… At POMAR, Nodipecten ‘babies’ are artificially mass produced and reared under the protected conditions of the lab environment for at least 12 days. They then settle down on rigid surfaces provided for them. Passing through a metamorphosis they grow in their adult ‘benthic’ form, looking much more like their parents, as a little two-valve mollusk! We had a peek at some 11 day old planktonic babies, under the microscope just a day before they should be ‘settling’ down for their adult life.
| 11 day old planktonic scallop larvae observed by keen UA Dallas budding scientist |
| Juvenile Scallop rearing tanks at POMAR |
| Our group with scallop rearing lanterns of varying capacities |
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| Samantha and Rachel observing future seafood |
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| Machelli and a juvenile Nodipecten nodosus scallo |
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| Scallop rearing lantern - 10,000 individuals here... |
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| Dr Zaganelli, Jessica, Machelli, Rachel, Samantha, Dr Scott, Emily and Ms Haley |
1 comment:
Well here am I sitting at a desk on a Sunday afternoon, and you guys out there having all the fun.
This looks like the sort of course that would make you fall in love with oceanography for life. Although I'm confused about the penguin. I think he needs a new GPS (global penguin system).
Phil, you're only making me jealous!
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