Florida Seafood Safety and Sustainability

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1 January February, 2011 Volume 52, Number 1 Florida Seafood Safety and Sustainability 2011 Brown Bag Lunch Webinar Series This FREE webinar series will educate seafood lovers about the sustainability and safety associated with some of Florida s most commercially valuable seafood products. The series will help consumers make informed decisions about purchasing and eating Florida Seafood. You will also learn how seafood makes it from the ocean to your table and how it is managed. Never participated in a webinar? Trust me, it is pretty easy. For more information and to sign up, contact Bryan Fluech, Collier County Sea Grant Extension Agent at Fluech@ufl.edu. Photo: Bryan Fluech Webinar Schedule 12:15 PM 12:45 PM Mar 16 Shrimp May 18 Snapper Sept 21 Spiny Lobster Nov 16 Oysters Cortez Commercial Fishing Festival a Smashing Success The Cortez Fishing festival attracted a crowd estimated at 25,000. Festival goers seemed to be delighted with the move of the Festival to the east end of town. Approximately $75,000 was raised to support the expansion and restoration of the FISF Preserve.

2 Did Fishermen Discover the New World? By John Stevely This is amazing. Basque fishermen (folks from a region in northwest Spain and part of France) were harvesting cod from the grand banks off of Newfoundland and the U.S. centuries before Christopher Columbus claimed discovery of the new world in Their production of cod Atlantic cod Gadus morhua produced great wealth and was a source of mystery to other European countries who couldn t figure out where they were fishing. When Jacques Cartier discovered the mouth of the St. Lawrence River in 1534, he also found a fleet of 1,000 Basque fishing boats. These fishermen were indeed intent on keeping their fishing grounds a secret! Sounds like some of my modern day fishing buddies. Why was this such a valuable secret? Dried salted cod was an incredibly valuable item of commerce for a number of reasons. During the Middle Ages food spoilage was a chronic problem. Properly dried and salted cod is an extremely durable food product. Because it has a very low fat content it will last much longer than other dried and salted fish. Also, when properly restored by soaking in water it produces a tasty white flaky flesh. Furthermore, it was in even greater demand due to the establishment of fasting days by the medieval church which forbade the consumption of red meat on these days. These fasting days included every Friday, 40 days of Lent, and other days of note on the religious calendar, and consequently totaled almost half of the days in the year. Thus there was a huge market. If I remember my history correctly, the reason Columbus was sailing around the world was to discover a new route to the sources of spice in Asia. Spice was so valuable because it made suspect food more palatable. Makes you realize how important the invention of refrigeration was in modern times. Once the discovery was out, there was a sort of gold rush for cod. By the middle 1500s 60% of all fish eaten in Europe was cod. The cod was so important to New England's early economy that a carved wooden cod was hung in the Massachusetts House of Representatives in Boston. This is certainly a piece of history I was not aware of. We don t hear much about the seafaring nature of the Basque people. Perhaps this is not so surprising, as the Basque people are an enigmatic group. The origin of their language is unknown and the origin of the people is not found in recorded history. These are the folks that invented the unique game of jai alai. The information in this article comes from the book Cod by Mark Kurlansky I highly recommend it for some fascinating reading. What is present day status of Atlantic Cod? Today, this stock is reported to have decreased by 96% since the 1850s. Moratoriums in the region, in place on and off for the past few decades, do not seem to have worked, and the stock has been depleted to the point where scientists are unsure if it will ever recover. Now that the cod stocks have markedly decreased, their prey (herring, shrimp and snow crabs) have had a population explosion, and now support valuable fisheries.

3 Protecting Florida's Spiny Lobster Fishery As commercial and recreational landings of Florida s spiny lobsters continue to remain below historical levels, new findings about the lobster s ecology are helping guide management strategies to benefit future populations and the fishing industry. Spiny lobsters are one of the largest commercial fisheries in Florida, and one of the most economically valuable in the Caribbean. In the five years leading up to 2001, commercial fishermen in Florida landed an average of nearly 7 million pounds of spiny lobsters each year, worth on average more than $28 million dockside. And then, landings dropped off sharply. For the past 10 years, commercial landings have averaged just 4 million pounds each year, generating about $20 million dockside. A virus contributes to the decline Don Behringer, a marine ecologist at the University of Florida, has been studying the effects of the lethal PaV1 The Caribbean spiny lobster is one of Florida s most valuable fisheries. (UF/IFAS) View this article and other features at Florida Sea Grant, virus that has been killing juvenile lobsters and potentially hurting the commercial and recreational fisheries. Behringer, in fact, discovered the virus while sampling juvenile lobster populations in the Florida Keys in The virus, the first identified for any lobster in the world, has since been reported in Mexico, Belize, Cuba, St. Croix, and St. Kitts, and is suspected to be widespread in the Caribbean. Behringer s ongoing research continues to study the transmission of the virus how it is spread between individuals in the population as well as on a larger scale throughout the Caribbean. Recently, Behringer used Florida Sea Grant funding to determine how lobster traps, the primary means of capture by the commercial fishery in Florida, could impede trap function or contribute to the prevalence of PaV1. We asked if current practices in the fishery compromise lobster resistance to infection, increase disease transmission rates, or if the presence of infected lobsters affects the capture efficiency of traps, Behringer said. We knew that the fishing industry and the Florida Fish and Wildlife Conservation Commission would benefit by using the results to manage the fishery with respect to PaV1 infection dynamics.

4 Indirect impacts on juvenile lobster survival One of Behringer s primary objectives in the study was to determine if a trapped lobster carrying the PaV1 virus would attract other lobsters in the trap, or if healthy lobsters could detect the diseased lobster and avoid the trap. Traps exploit the gregarious, or social nature of young and adult lobsters, because they typically contain other lobsters, but are impenetrable to most predators. In the natural environment, Behringer says, this behavior affects the ability of young lobsters to survive into adulthood. Lobsters view traps as nothing more than a shelter from which only the larger lobsters cannot escape, Behringer said. Small, under sized lobsters are capable of moving freely into and out of the traps, but we were unsure about trap use between healthy and diseased lobsters. Behringer s previous research had shown that healthy lobsters were able to detect and avoid lobsters infected with the PaV1 virus, most likely through a chemical cue. (Recent findings confirm this.) With the assistance of local commercial fishermen, the research team deployed traps containing either a diseased or a healthy lobster. Then, a week later, they pulled the traps to see how they functioned. Indeed, traps with diseased lobsters attracted significantly fewer lobsters, Behringer said, indicating that a trap into which a PaV1 infected lobster has moved will attract fewer lobsters than those containing only healthy lobsters. This avoidance may reduce infection risk, but it also means potentially lower landings for those traps. Furthermore, because healthy lobsters avoid taking shelter with a diseased lobster, it could increase their risk from predators. New research directions Behringer s research also looked at the effect of temperature on the infection. Experiments found that lobsters held in the lab in high temperature seawater and exposed to PaV1 developed active and more intense infections much more quickly than those held at lower temperatures. The finding could become important given rising temperatures in the global oceans. High temperature, even in small increments, often results in stress that can increase the susceptibility of organisms to infection and potentially alter the time course of infection, Behringer said. In future projects we re going to test if water temperature may affect disease susceptibility and infection progress. Behringer was also recently funded by the National Science Foundation for a multi year, $1.4 million grant to study the dynamics of the PaV1 virus throughout the Caribbean wide range of the spiny lobster. The findings will continue to provide fishermen and fisheries managers with a better understanding of how the deadly PaV1 disease spreads in spiny lobsters, which they then hope to use to implement management plans that reduce the impact of the disease.

5 Migrating Sea Turtles Have Magnetic Sense for Longitude Adapted from ScienceDaily.com, Feb. 28, 2011 From the very first moments of life, hatchling loggerhead sea turtles have an arduous task. They must embark on a transoceanic migration, swimming from the Florida coast eastward to the North Atlantic and then gradually migrating over the course of several years before returning again to North American shores. Now, according to an article from ScienceDaily.com, researchers have figured out how the young turtles find their way. One of the great mysteries of animal behavior is how migratory animals can navigate in the open ocean, where there are no visual landmarks. The most difficult part of open sea navigation is determining longitude or east west position. It took human navigators centuries to figure out how to Photo courtesy of NOAA. determine longitude on their longdistance voyages. It appears that the turtles pick up on magnetic signatures that vary across Earth's surface in order to determine their position in space both east west and north south and steer themselves in the right direction. Although several species, including sea turtles, were known to rely on magnetic cues as a surrogate for latitude (a measure of your north south position on the earth), the findings come as a surprise because those signals had been considered unpromising for determining east west position. The loggerheads' secret is that they rely not on a single feature of the magnetic field, but on a combination of two: the angle at which the magnetic field lines intersect Earth (a parameter known as inclination) and the strength of the magnetic field. Near the Equator, the field lines are approximately parallel to Earth's surface. As one travels north from the Equator, the field lines grow progressively steeper until they reach the poles, where they are directed straight down into Earth. The magnetic field also varies in intensity, being generally strongest near the poles and weakest near the equator. Both parameters appear to vary more reliably from north to south than east to west, which had led many researchers to conclude that the magnetic field is useful only for latitudinal information. What had been overlooked before is that inclination and intensity vary in slightly different directions across Earth's surface. As a result of that difference, particular oceanic regions have distinct magnetic signatures consisting of a unique combination of inclination and intensity. The researchers made the discovery by subjecting hatchlings to magnetic fields replicating those found at two locations, both along the migratory route but at opposite ends of the Atlantic Ocean. Each location had the same latitude but different longitude. The turtles were placed in a circular water filled

6 arena surrounded by a computerized coil system used to control the magnetic field and tethered to an electronic tracking unit that relayed their swimming direction. Turtles exposed to a field like one existing on the west side of the Atlantic near Puerto Rico swam to the northeast. Those exposed to a field like that on the east side of the Atlantic near the Cape Verde Islands swam to the southwest. The findings may have important implications for the turtles, the researchers say. One of the study authors stated, "This work not only solves a long standing mystery of animal behavior but may also be useful in sea turtle conservation. Understanding the sensory cues that turtles rely on to guide their migrations is an important part of safeguarding their environment." The discovery may also lead to new approaches in the development of navigational technologies, the researchers added. Seahorses Star in New Mote Show Seahorses are the stars of a new tour at Mote Marine Aquarium. One of Tampa Bay s most engaging creatures is starring in a new tour at Mote Marine Aquarium on Longboat Key. Seahorses live in tropical waters around the world and are considered indicator species because they require stable ecosystems. The new tour highlights the threats seahorses face in the wild along with an in depth look at how Mote is breeding them for conservation. Tours are scheduled on most Thursdays and tickets must be purchased in advance. Photo courtesy of Mote Marine Aquarium Along with concerns about shrinking habitat, seahorses are harvested around the world for traditional medicines, the souvenir trade and for aquaria. More than 25 million seahorses are consumed annually, causing concern that wild populations are becoming depleted. To reduce the pressure on these fascinating fish, Mote raises seahorses that are later displayed in more than 40 aquaria, zoos and science institutions around the country. Not only is it important to raise seahorses, but educating people about them is also key, said Seahorse Conservation Laboratory Supervisor Shawn Garner, who leads the tours and is among the country s most accomplished seahorse aquarists. Only when you learn about seahorses can you fully comprehend their beauty, their uniqueness in the animal world and why we need to protect them. To purchase tickets, call , ext. 536, or e mail groupsales@mote.org. Source: Bay Soundings

7 Florida Sea Grant Extension Agent Newsletter Contributors John Stevely, Manatee, Hillsborough, Sarasota counties: Betty Staugler, Charlotte Count: Joy Hazell, Lee County: Bryan Fluech, Collier County: More information on the Florida Sea Grant College Program can be found at: Florida Sea Grant Share this newsletter with friends and colleagues! They can also subscribe by ing me,