Local Research Institutions Working to Restore Florida Keys Coral Reefs

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1 Local Research Institutions Working to Restore Florida Keys Coral Reefs July August 2007 Volume 49 3 Coral might be the slowest-growing crop ever farmed, but researchers say damaged reefs could be repaired faster if they perfect methods to cultivate the marine organisms. The Florida Aquarium, working with researchers from the University of Florida s Tropical Aquaculture Laboratory in Ruskin and Mote Marine Laboratory s Summerland Key station, is helping to make that happen. With the loss of naturally growing coral, it is imperative we determine the causes of its destruction and then methods to supplement the loss with new growth, like seeding native waters with healthy coral fragments, said Ilze Berzins, vice president of biological operations for the Florida Aquarium. Seven coral species were harvested from an underwater sea wall at the U.S. naval base in Key West Harbor. Planned sea wall construction threatened to encase or destroy existing corals. Last year, almost 160 cookie-sized coral fragments were placed at a reef near Key West where a freighter ran aground in Fragments placed at the Key West site had been managed in one of three ways. One set was raised in a Ruskin greenhouse, held in tanks of artificial seawater. Another was cultured at the Mote Marine Laboratory facility at Summerland Keys, using an outdoor system with seawater pumped from offshore. A third was placed on the damaged reef almost immediately after harvest. Each fragment is numbered so it can be tracked. If you grow coral in a greenhouse in a land-based system and put it in the wild, will it survive? asks Craig Watson, director of the Tropical Aquaculture Laboratory. There are those who say no, because it will be acclimated to those conditions where it grew and

2 it can t survive elsewhere. We don t believe that, and we are setting out to prove that wrong. Source: Bay Soundings, Spring Bay Scallops in Sarasota Bay Earlier this spring, there were some interesting reports from local fishing guides that were finding dime sized bay scallops in their cast nets. Just recently, a local school group found some adult size scallops off of Emerson Point (bay scallops grow extremely rapidly in April-June). This might prove to be the best year for scallops in local waters in the past 30 years, since they essentially disappeared in the early 1970 s. Occasionally, small numbers of scallops have been found in Sarasota Bay (several years ago I found enough to provide brood stock and to conduct genetic studies). So, I am not convinced that we are seeing anything like complete recovery of bay scallops (their abundance widely varies from year to year), but lets hope this is a positive sign. More to come in the next newsletter! Drying the American Southwest The large human population and widespread industrial and agricultural economies of the southwestern United States and northern Mexico depend on the cheap and ready availability of water that may be affected by changes in precipitation, evaporation, groundwater storage, and river flow as climate warms. A broad array of climate models agree that this region will dry substantially during the next century and that conditions as dry as those of the Dust Bowl will become the normal ones in the region. These changes would be caused by atmospheric circulation patterns that create a pole ward expansion of the subtropical dry zones. This aridification should be unlike any climate state that exists in the instrumental record. Source: Science Magazine Vol. 316, May Ladies Angle for Fishing Skills at Ladies, Let s Go Fishing! St. Petersburg Seminar, Oct , 2007 Women of all angling abilities can acquire and fine-tune fishing skills at the award winning Ladies, Let s Go Fishing! seminar! Hosted by Florida s Fish and Wildlife Conservation Commission (FWC) and presented by Mercury Outboards, the program offers a full weekend of educational fishing activities on Oct at the Holiday Inn Harborside, Indian Rocks Beach. 2

3 Contact: LLGF, P.O. Box , Fort Lauderdale, FL 33355, phone , fax , toll free information LLGF (5543), website: The Upside-Down Jellyfish in Sarasota Bay Has Anyone Seen This Organism in Tampa Bay and to the North? Keen observers of Sarasota Bay shallow waters may have noticed that there appears to have been a rather large increase in abundance in recent years of the Upside-Down Jellyfish (Cassiopeia xamachana). Most folks familiar with this creature commonly associate it with shallow, protected areas in the Florida Keys. If you have seen this organism in Tampa Bay or to the north, please let me know. The Upside Down jellyfish is a weird looking creature. Many of us are most familiar with the medusae jellyfish form of jellyfish nearly transparent bell shaped organism gently pulsating in a weak swimming motion, often with trailing tentacles. The common name Upside-Down Jellyfish is very descriptive. It is simply a jellyfish which has mostly lost its swimming habit and lies upside-down on the bay bottom, exposing greenish frilly membranes directly to sunlight. In a manner of speaking, the Upside-Down jellyfish has become a farmer, the coloration in the frilly membranes is caused by the presence of symbiotic algae within the jellyfish tissue. The algae help provide nutrition and some think that oxygen generated by the algae helps the jellyfish survive in waters with low levels of dissolved oxygen. Figure 1 Biologists classify jellyfish as belonging to a major group of animals called Cnidarians which also includes corals and sea anemones. One of the defining characteristics of this group of animals is that they have stinging cells called nematocysts (Figure 1). These stinging cells can fire harpoon like projectiles that can contain poison to capture small prey items for food. In most jellyfish, these stinging cells are so small they can t penetrate human skin. The Upside-Down jellyfish has fairly harmless stinging cells, but if you handle them you will most probably experience some stinging sensation. However, some jellyfish can have a potent toxin that can cause severe pain or even death. Although rarely seen in local waters, you definitely want to avoid the jellyfish called the Portuguese man-of-war (trust me on this). If stung, splash with water to cleanse. If you rub the wound, you could trigger more stinging cells. Pouring 3

4 something acid on the wound will help, some soft drinks (Pepsi or Coke) red wine (I would probably drink the wine instead) or even urine will work (source: Scientific America). Note: using urine is not recommended or endorsed by the University of Florida. Jellyfish reproduction is one of those facts can be stranger than fiction type of stories. Reproduction involves both sexual and asexual stages (biologists refer to this as alternation of generations ). The adult medusa form (free swimming bell shaped form) reproduces sexually releasing eggs and sperm into the water (Figure 2). The fertilized egg develops into a planula larvae that hooks on to the bottom and grows into another form called the polyp. The polyp resembles a miniature sea anemone. This stage can last a long time, perhaps as long as years in some cases. During this stage, the polyps can reproduce asexually cloning or budding themselves to eventually produce yet another stage of jellyfish life, called the ephyra. It is this form that grows into the adult medusa jellyfish. Figure 2 Rain Sensor Rebate Available to Manatee County Customers Residents using potable water from Manatee County Utilities who do not have a working rain sensor on a system installed before September 1998 may be eligible for a $50 rebate if they install an approved rain sensor. Sensors cost $30 or $100 to $125 if professionally installed. The rebate is funded through a new Southwest Florida Water Management District grant administered by the Manatee County Extension Service. For an application, go to or call Source: Bay Soundings, Spring

5 Tampa Bay Gains Seagrasses Tampa Bay has gained nearly 1,300 acres of seagrass since 2004, and now supports more seagrass than at any time measured since the 1950 s, according to newly released data presented to the Tampa Bay Estuary Program (TBEP). Additionally, water clarity in the bay is also the best it has been since record-keeping began, with all major bay segments meeting targets. Overall, the amount of seagrasses in Tampa Bay increased by 4.7% from , according to surveys conducted by scientists with the Southwest Florida Water Management District s Surface Water Improvement and Management (SWIM) Program. Seagrasses which generally grow in waters less than six feet deep are an important barometer of the bay s health because they require relatively clean water to flourish. The results indicate that Tampa Bay has about 28,299 acres of seagrass far less than the Estuary Program s goal of 38,000 acres, but the highest recorded total since the benchmark 1950 s period adopted by the program. Water clarity also is meeting goals for all bay segments for the first time since scientists began tracking water quality in the 1970 s. Although the overall report card on the bay s health is positive, not all bay segments experienced seagrass expansion. Significant declines were noted in Middle Tampa Bay which lost 1,180 acres of seagrass from and in Hillsborough Bay, with a loss of 151 acres of seagrass during that time frame. Conversely, the area generally north of the Gandy Bridge, known as Old Tampa Bay, experienced a 16% increase in seagrasses from good news for an area that had been steadily losing seagrasses for a decade. Source: Bay Soundings, Spring The National Estuary Program Celebrates 20 th Birthday The National Estuary Program celebrates 20 years of community-based watershed management in Created by Congress through amendments to the federal Clean Water Act, the program designated 28 estuaries of national significance including Tampa Bay and provides annual funding to help develop and implement comprehensive management plans to improve those waterways. The Tampa Bay Estuary Program was nominated to the national program in 1987 and designated in Source: Bay Soundings, Spring

6 Melting Faster Observations of the extent of Arctic sea ice in September at the end of the melt season, when ice coverage is at its annual minimum have shown a large decline over the past several decades, consistent with current qualitative understanding of natural variability and the effects of a warming climate. Nearly all climate models predict that September Artic Sea ice extent will continue to decline through the 21 st century, largely in response to rising concentrations of atmospheric greenhouse gases. How well do observations and models agree, though? To answer that question, Stroeve et al. compared the output of the more than a dozen models participating in the Intergovernmental Panel on Climate Change Fourth Assessment Report that calculated sea ice. They found that nearly all of the models overestimated annual minimum Arctic sea ice area, in many cases by large amounts. These findings have two important implications: first, that the effect of rising greenhouse gases may have been more important than has been believed; and second, that future loss of Arctic sea ice may be more rapid and extensive than predicted. Source: Science Magazine Vol. 316, May Sincerely, John Stevely Sea Grant Extension Agent 6