BY JACK SHORT - On Thursday, April 25 incoming president and CEO of Mote Marine Laboratory Dr. Michael Crosby opened the last in a series of five lectures outlining the directives central to the Mote/Boca Grande partnership, a presentation about snook and tarpon stock enhancement.
He emphasized the importance of research being put to good use in the community, and that Mote was founded on philanthropy and research.
“That’s our heart and soul, that’s our core,” Crosby said.
Because Mote is an independent institution, he said, they must rely on partnerships with the community and other institutions for support.
Mote’s “2020 Vision” includes efforts to connect their research to sustainability as well as economic growth, Crosby said.
That economic growth may come from programs such as biomedical research that they hope will lead to tools that can be used to fight cancer, and, indirectly, their tarpon and snook restocking and habitat protection programs.
Dr. Kenneth Leber, senior scientist and director of their fisheries and aquaculture program, presented, alongside Dr. Kevan Main, president of the World Aquaculture Society and director of Mote’s 200-acre aquaculture park.
Main’s aim is to develop and improve aquaculture technology that will allow them to raise stock that can be introduced to the natural environment. Leber’s work focuses on understanding how to most effectively add stock to area waters by identifying and protecting habitats vital to the success of stocked fish and determining optimal conditions under which to introduce those fish.
Leber said his field was basically uninhabited when he began 25 years ago, and much needs to be done before scientists can understand and gauge the effectiveness of stock enhancement programs.
This is important work because the economic impact of sport fishing on Florida is $8.6 billion, $6.9 billion of which is the output from saltwater fishing, Leber said, citing a 2011 study by the American Sport Fishing Association.
But in order to maintain the health of that industry, he said, Florida must manage its fisheries.
“We need studies that show how fish habitats are truly integral in maintaining and sustaining viable populations,” Leber said.
He said Charlotte Harbor is fortunate to have plenty of good habitat with shoreline vegetation that is so critical for the protection it affords juvenile fish, and the protection and restoration of that habitat is crucial to sustain the current quality of fishing.
Controlling mortality through regulation and responsible restocking are equally important, he said. Responsible use of genetics, understanding what has led to declines, and the use of experiments to determine the effectiveness of stocking efforts all contribute to a plan for responsible stock enhancement.
In Hawaii in the 1980s Leber said he lost entire stock populations before he learned the importance of choosing where and when to release fish. To that end, when he came to Florida to work with snook, he began by evaluating release sites with small-scale experimental releases.
Leber and his associates also found that care must also be taken not to displace natural populations or even previously restocked populations by overstocking, he said.
Tarpon stocking is still in its developmental stage, he said, partially because less is understood about larval food and behavior patterns.
He also said funding for stock enhancement for snook has declined due to the recession, which is why they are not stocking right now in Sarasota.
Dr. Main said they still need to improve the technology and achieve a better understanding of snook nutritional needs in order to produce the amount of fish that would be needed for a large-scale stock enhancement program.
Main also said the focus of the technology development and aquaculture activities at Mote are aimed at producing stock enhancement fish or fish for consumption with minimal impact on the environment.
Genetics of the animals being used are possibly the most important factor, she said, because they can be used to identify the “better performers.”
“(Genetics) shows us who’s participating, are they spawning multiple days in a row, … ,” she said. “Some fish are carrying the majority of the weight.”
They are also working to identify the optimal culture conditions for all life stages in the hatchery. This includes the right food that can be produced in sufficient number, aeration, current, lighting and more. They are also very delicate during certain stages of life.
“If you even look at the tank sideways you can wind up with them keeling over,” Main said.
Some other problems Main and her associates have been working to reduce are cannibalism and deformities among fingerlings, she said, and, finally, to condition the snook for release into the wild.
Main reinforced the idea that tarpon present a unique set of challenges, and research on them with regards to stock enhancement and aquaculture lags behind snook research.
For example, she said, tarpon only develop organs that allow them to eat normally after about 70 days. Until then they absorb food through their skin.
“It’s definitely not your standard fish in terms of reproducing them in captivity,” Main said.
She and her associates hope to work with researchers in Japan, one of the only other places in the world trying to develop an aquaculture program for tarpon.
View More images >>
E-mail (required, but will not display)
Notify me of follow-up comments
Click for a larger view