Florida Waters Research Articles

Problems associated with a lipofuscin extraction method used to age blue crabs Callinectes sapidus cultured in Florida, USA

The blue crab Callinectes sapidus is an ecologically and economically important component of marine and estuarine ecosystems of the western Atlantic and Gulf of Mexico. Cur- rent stock assessments lack a clear understanding of the age structure of blue crab populations in Florida (USA). Blue crabs and other crustaceans are especially difficult to age because of the com- plex nature of their discrete, rather than continuous, growth patterns. Chesapeake Bay re - searchers developed a method of aging blue crabs by assaying the aging pigment lipofuscin extracted from eyestalk nerve tissue. Here we investigated the usefulness of that method in deter- mining the age of blue crabs inhabiting Florida waters. Assays of a wild-caught, young-of-the- year cohort that was pond-raised revealed a negative linear trend in lipofuscin indices over an 18 mo culture period. Assays of a tank-raised cohort of captive-bred crabs of known age also showed no relationship between the lipofuscin index and age over an 11 mo period. These results suggest that lipofuscin assays, as used in the Chesapeake Bay populations, are not useful in deter- mining the age of blue crabs in Florida waters. Further study is warranted to determine how the procedure might be modified for Florida blue crab populations.

The potential role of benthic nutrient flux in support of Karenia blooms in west Florida (USA) estuaries and the nearshore Gulf of Mexico

The project “EcoHAB: Karenia Nutrient Dynamics in the Eastern Gulf of Mexico” (NOAA EcoHAB grant NA06NOS4780246) was designed to simultaneously quantify a wide variety of nutrient sources which can support the nearly annual blooms of Karenia brevis in the estuarine and coastal waters of west central Florida. Estuarine outflows and water column stocks of nutrients have been previously demonstrated to be insufficient to support the observed cell densities (>106cellL−1) which K. brevis can achieve. Nutrients released from sediments, however, are a nutrient source common to offshore, coastal, and estuarine environments. Prior regional measurements were generally lacking, particularly in coastal waters. Dark-only nutrient fluxes from the sediments were directly measured using large (65L, 0.27m2), in situ, opaque, stirred chambers deployed over 5–8h. Stations were located in coastal waters, a lagoonal system, and in the lower portions of two major estuaries, Tampa Bay and Charlotte Harbor, and were sampled during the fall of 2007–2009. Field procedures included triplicate chambers at each station and a water column control. Fluxes were quantified for dissolved oxygen, and dissolved ammonium, nitrate-nitrite, urea, total nitrogen, orthophosphorus, total phosphorus, and silica. Fluxes were dominated by dissolved silica (900–13,800μmolm−2d−1), ammonium (430–3360μmolm−2d−1) and ortho-phosphorus (50–1200μmolm−2d−1) and were greater than literature values which had been previously incorporated in local ecological modeling efforts. Based on literature growth rates and on cell complement data, the measured sediment flux of nutrients could have provided up to 300% of P requirements, and up to 100% of N requirements of 50,000cellsL−1 of K. brevis, modified by water depth. Flux values, derived from dark incubation and applied to Karenia cells only, likely represented an upper boundary of sediment contributions to Karenia nutrient budgets. Density stratifications common to upwelling coastal plumes and migratory behavior of K. brevis would have increased the percentage of supply afforded by sediment flux. Despite ammonium to ortho-phosphorus ratios in sediment flux substantially less than Redfield, ammonium flux provided a larger fraction of growth needs due to low levels of water column DIN concentrations (averaging 1.0μmolL−1). Fluxes enriched in P were consistent with bulk sediment P and the P-enriched geology of the region, and would have complemented N supplied by common nitrogen fixers such as Trichodesmium sp.

Fishery gear interactions from stranded bottlenose dolphins, Florida manatees and sea turtles in Florida, U.S.A

Documenting the extent of fishery gear interactions is critical to wildlife conservation efforts, especially for reducing entanglements and ingestion. This study summarizes fishery gear interactions involving common bottlenose dolphins (Tursiops truncatus truncatus), Florida manatees (Trichechus manatus latirostris) and sea turtles: loggerhead (Caretta caretta), green turtle (Chelonia mydas), leatherback (Dermochelys coriacea), hawksbill (Eretmochelys imbricata), Kemp’s ridley (Lepidochelys kempii), and olive ridley (Lepidochelys olivacea) stranding in Florida waters during 1997–2009. Fishery gear interactions for all species combined were 75.3% hook and line, 18.2% trap pot gear, 4.8% fishing nets, and 1.7% in multiple gears. Total reported fishery gear cases increased over time for dolphins (p<0.05), manatees (p<0.01), loggerheads (p<0.05) and green sea turtles (p<0.05). The proportion of net interaction strandings relative to total strandings for loggerhead sea turtles increased (p<0.05). Additionally, life stage and sex patterns were examined, fishery gear interaction hotspots were identified and generalized linear regression modeling was conducted.

Common Sharks of Florida

Florida’s shark population is diverse and includes species that range in size from only a few feet to more than 40 feet in total length. Experts caution sea-goers to beware of sharks 6 feet or longer due to the damage they can cause in a single bite. Among the species that grow to this size and have been known to attack humans are bull sharks, tiger sharks, and great white sharks. Whites are seasonal visitors to Florida waters, and bulls and tigers are year-round residents, along with these other common species. This revised 4-page fact sheet was written by Florida Sea Grant, and published by the UF Department of Sea Grant, September 2013.

Florida’s Underwater Archaeological Preserves: Public Participation as an Approach to Submerged Heritage Management

Florida waters are home to the remains of such diverse watercraft as galleons, freighters, sailing yachts, steamboats, and prehistoric canoes. Managing these resources, especially regarding questions of access versus preservation, can be a daunting task. Florida’s Underwater Archaeological Preserves programme is an experiment in public participation to further both the awareness and the preservation of submerged heritage through site conservation and interpretation, incorporating various stakeholders during each step in the process. The logic in Florida’s Preserves programme is that an involved public given free access to a shipwreck site can be an ingredient for, instead of a hindrance to, preservation. Although one of several programmes worldwide, the concept that sets Florida’s Underwater Archaeological Preserves programme apart is its use of public involvement to promote education that fosters attitudes of conservation and preservation. If the public feels a share as stakeholders in the preservation of their maritime heritage, then submerged cultural resources will be more effectively protected.

Effects of a non-native cichlid fish (African jewelfish, Hemichromis letourneuxi Sauvage 1880) on a simulated Everglades aquatic community

In an 8-month mesocosm experiment, we examined how a simulated Everglades aquatic community of small native fishes, snails, and shrimp changed with the addition of either a native predator (dollar sunfish Lepomis marginatus) or a non-native predator (African jewelfish Hemichromis letourneuxi) compared to a no-predator control. Two snail species (Planorbella duryi, Physella cubensis) and the shrimp (Palaemonetes paludosus) displayed the strongest predator-treatment effects, with significantly lower biomasses in tanks with Hemichromis. One small native fish (Heterandria formosa) was significantly less abundant in Hemichromis tanks, but there were no significant treatment effects for Gambusia holbrooki, Jordanella floridae, or Pomacea paludosa (applesnail). Overall, there were few treatment differences between native predator and no-predator control tanks. The results suggest that the potential of Hemichromis to affect basal food-web species that link primary producers with higher-level consumers in the aquatic food web, with unknown consequences for Florida waters.

Postnesting migratory behavior of loggerhead sea turtles Caretta caretta from three Florida rookeries

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 21:129-142 (2013) - DOI: https://doi.org/10.3354/esr00512 Postnesting migratory behavior of loggerhead sea turtles Caretta caretta from three Florida rookeries Allen M. Foley1,*, Barbara A. Schroeder2, Robert Hardy3, Sandra L. MacPherson4, Mark Nicholas5, Michael S. Coyne6 1Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, Jacksonville Field Laboratory, Jacksonville, Florida 32218, USA 2National Marine Fisheries Service, Office of Protected Resources, Silver Spring, Maryland 20910, USA 3Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, St. Petersburg, Florida 33701, USA 4US Fish and Wildlife Service, Jacksonville, Florida 32256, USA 5National Park Service, Gulf Islands National Seashore, Gulf Breeze, Florida 32563, USA 61 Southampton Place, Durham, North Carolina 27705, USA *Email: allen.foley@myfwc.com ABSTRACT: We used satellite telemetry to study postnesting migrations of 42 loggerhead sea turtles Caretta caretta from 3 Florida rookeries. Postnesting migrations ended in neritic (<200 m) waters of Florida, Alabama, Texas (USA), and of Mexico and the Bahamas. Most postnesting migrations were restricted to the continental shelf and were relatively direct. Migrations through oceanic areas (>200 m) tended to be less direct, largely due to apparent influences of the Florida Current in the Atlantic and to looping travel paths (often along edges of mesoscale eddies of the Loop Current) in the Gulf of Mexico. The largest loggerheads tended to migrate to foraging grounds that were farthest from the nesting beach. Turtles spent more time near the surface (<3 m) when migrating than they did during residency at foraging sites, and were likely swimming just below the surface. The substantial amount of time spent near the bottom in neritic areas and the looping travel paths in oceanic areas indicate that migrating loggerheads may have been foraging. We identified 4 migratory corridors. Two were on the continental shelf of the Florida Panhandle, 1 was along the northern coast of Cuba, and 1 was along the southeastern coast of Florida. Migrating loggerheads may be uniquely vulnerable to mortality factors because of where they travel and how they behave, particularly if they are concentrated in narrow (perhaps <10 km wide) migratory corridors. Characterizing the behavior and identifying the travel paths of loggerheads during postnesting migrations are necessary steps for implementing successful recovery efforts. KEY WORDS: Caretta caretta · Sea turtle · Postnesting migration · Satellite tracking · Telemetry · Migratory corridor Full text in pdf format PreviousNextCite this article as: Foley AM, Schroeder BA, Hardy R, MacPherson SL, Nicholas M, Coyne MS (2013) Postnesting migratory behavior of loggerhead sea turtles Caretta caretta from three Florida rookeries. Endang Species Res 21:129-142. https://doi.org/10.3354/esr00512 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 21, No. 2. Online publication date: August 13, 2013 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2013 Inter-Research.

Sampling Gear Efficiency and Selectivity for Juvenile Ladyfish Elops Saurus in Florida Waters (USA)

At the foundation of managing wildlife is collecting accurate field data with appropriate sampling gears and methods under a strict experimental design and standardized protocols. To elucidate, monitor, and predict wildlife patterns in space and time requires the selection of specific sampling gears for the community or species of interest, especially for species that display spatial and temporal variability in distribution and abundance. Among the most challenging types of wildlife to examine in the field are marine fisheries resources given their expansive range, spatial and temporal distribution, and specific early life-history characteristics (e.g., habitat, environmental conditions, and recruitment patterns). Numerous studies have investigated the catch efficiency for various sampling gears and techniques; however, no information has ever been reported for ladyfish (Elops saurus), an economically valuable species in the southeastern United States and other world-wide regions. Given the importance of collecting ladyfish early life-history information, the purpose of this investigation was to evaluate, for the first time, the efficiency and selectivity of various field-sampling gears used in Florida waters to collect juvenile ladyfish. The specific objectives were to examine the sampling gear efficiency and selectivity on juvenile ladyfish relative abundance and length-frequency distribution among different water bodies. This investigation found that juvenile ladyfish abundance, size, and length frequency distribution significantly varied by sampling gear. In addition, the findings revealed that the most efficient gear for sampling juvenile ladyfish smaller than 100 mm SL were seines with an offshore deployment method. Despite detecting length frequency differences among sampling gears, no clear pattern was evident among estuaries. In general, seine catch efficiency decreased and gillnet efficiency increased with ladyfish size. To alleviate gear or sampling bias, results demonstrated that researchers need to use a variety of sampling gears to sample ladyfish.

Hyotissa mcgintyi Found In North Carolina [Mollusca, Bivalvia, Gryphaeidae

Hyotissa mcgintyi Found In North Carolina [Mollusca, Bivalvia, Gryphaeidae

Swim Speed, Behavior, and Movement of North Atlantic Right Whales (Eubalaena glacialis) in Coastal Waters of Northeastern Florida, USA

In a portion of the coastal waters of northeastern Florida, North Atlantic right whales (Eubalaena glacialis) occur close to shore from December through March. These waters are included within the designated critical habitat for right whales. Data on swim speed, behavior, and direction of movement – with photo-identification of individual whales – were gathered by a volunteer sighting network working alongside experienced scientists and supplemented by aerial observations. In seven years (2001–2007), 109 tracking periods or “follows” were conducted on right whales during 600 hours of observation from shore-based observers. The whales were categorized as mother-calf pairs, singles and non-mother-calf pairs, and groups of 3 or more individuals. Sample size and amount of information obtained was largest for mother-calf pairs. Swim speeds varied within and across observation periods, individuals, and categories. One category, singles and non mother-calf pairs, was significantly different from the other two – and had the largest variability and the fastest swim speeds. Median swim speed for all categories was 1.3 km/h (0.7 kn), with examples that suggest swim speeds differ between within-habitat movement and migration-mode travel. Within-habitat right whales often travel back-and-forth in a north-south, along-coast, direction, which may cause an individual to pass by a given point on several occasions, potentially increasing anthropogenic risk exposure (e.g., vessel collision, fishing gear entanglement, harassment). At times, mothers and calves engaged in lengthy stationary periods (up to 7.5 h) that included rest, nursing, and play. These mother-calf interactions have implications for communication, learning, and survival. Overall, these behaviors are relevant to population status, distribution, calving success, correlation to environmental parameters, survey efficacy, and human-impacts mitigation. These observations contribute important parameters to conservation biology, predictive modeling, and management. However, while we often search for predictions, patterns, and means, the message here is also about variability and the behavioral characteristics of individual whales.

Abundance and Distribution of Sharks in Northeast Florida Waters and Identification of Potential Nursery Habitat

AbstractSharks are considered top predators in many marine ecosystems and can play an important role in structuring community ecology. As a result, it is necessary to understand the factors that influence their abundance and distribution. This is particularly important as fishery managers develop management plans for sharks that identify areas that serve as essential fish habitat, especially nursery habitat. However, our understanding of shark habitat use in northeast Florida waters is limited. The goal of this study was to characterize the abundance and distribution of sharks in northeast Florida estuaries and to examine the effect of abiotic factors on shark habitat use. A bottom longline survey conducted from 2009 to 2011 indicated that 11 shark species use the estuarine waters of northeast Florida during the summer months. Atlantic Sharpnose Sharks Rhizoprionodon terraenovae, Blacktip Sharks Carcharhinus limbatus, and Bonnetheads Sphyrna tiburo were the most abundant species and made up 81.4% of the total catch. Site, month, and bottom water temperature were the most important factors determining the presence and abundance of sharks and suggest both regional and seasonal variations in the use of northeast Florida waters. Depth, salinity, and dissolved oxygen were also important factors. Our data show that these waters serve as a nursery for Atlantic Sharpnose and Blacktip Sharks, with young‐of‐the‐year and juveniles being present in the summer months. Limited tag–return data reveal that juvenile sharks remain in these waters throughout the summer and that some return in subsequent summers. This is the first study to characterize the abundance and distribution of sharks and identify potential nursery areas in northeast Florida estuaries.Received October 10, 2012; accepted March 7, 2013

Diseases of oysters Crassostrea ariakensis and C. virginica reared in ambient waters from the Choptank River, Maryland and the Indian River Lagoon, Florida

To assess potential benefits and liabilities from a proposed introduction of Asian Suminoe oysters, susceptibilities of exotic Crassostrea ariakensis and native C. virginica oysters were compared during exposures to pathogens endemic in temperate, mesohaline waters of Chesapeake Bay and sub-tropical, polyhaline Atlantic waters of southern Florida, USA. Cohorts of diploid, sibling oysters of both species were periodically tested for diseases while reared in mesocosms receiving ambient waters from the Choptank River, Maryland (>3 yr) or the Indian River Lagoon, Florida (10 to 11 mo). Haplosporidium sp. infections (e.g. MSX disease) were not detected in oysters from either site. Perkinsus sp. infections (dermo disease) occurred among members of both oyster species at both sites, but infections were generally of low or moderate intensities. A Bonamia sp. was detected by PCR of DNAs from tissues of both oyster species following exposure to Florida waters, with maximum PCR prevalences of 44 and 15% among C. ariakensis and C. virginica oysters respectively during June 2007. Among C. ariakensis oysters sampled during April to July 2007, a Bonamia sp. was detected in 31% of oysters by PCR (range 11 to 35%) and confirmed histologically in 10% (range 0 to 15%). Among simultaneously sampled C. virginica oysters, a Bonamia sp. was detected in 7% by PCR (range 0 to 15%), but histological lesions were absent. Although this is the first report of a Bonamia sp. from Florida waters, sequences of small subunit (SSU) rDNA and in situ hybridization (ISH) assays both identified the Florida pathogen as Bonamia exitiosa, which also infects oysters in the proximate waters of North Carolina, USA.

Ensuring seafood identity: Grouper identification by real-time nucleic acid sequence-based amplification (RT-NASBA)

Grouper are one of the most economically important seafood products in the state of Florida and their popularity as a high-end restaurant dish is increasing across the U.S. There is an increased incidence rate of the purposeful, fraudulent mislabeling of less costly and more readily available fish species as grouper in the U.S., particularly in Florida. This is compounded by commercial quotas on grouper becoming increasingly more restrictive, which continues to drive both wholesale and restaurant prices higher each year. Currently, the U.S. Food and Drug Administration recognize 56 species of fish that can use “grouper” as an acceptable market name for interstate commerce. This group of fish includes species from ten different genera, making accurate taxonomic identification difficult especially if distinguishing features such as skin, head, and tail have been removed. This is leading regulatory agencies to employ genetic identification methods which tend to have much higher species-level resolution than phenotypic methods. Standard genetic identification methods are highly technical and require expensive lab-based equipment to perform, which often leads to longer turnover times. We have developed a generic grouper assay that detects the majority of the grouper species listed on the 2011 FDA Seafood List, including all of the species found in Florida waters. This assay is based upon real-time nucleic acid sequence-based amplification (RT-NASBA) targeting mitochondrial 16S rRNA for the accurate detection of grouper. This assay can be performed in fewer than 90 min with little potential for cross-reactivity from non-target species.

A Comparison of Spatial and Movement Patterns between Sympatric Predators: Bull Sharks (Carcharhinus leucas) and Atlantic Tarpon (Megalops atlanticus)

BackgroundPredators can impact ecosystems through trophic cascades such that differential patterns in habitat use can lead to spatiotemporal variation in top down forcing on community dynamics. Thus, improved understanding of predator movements is important for evaluating the potential ecosystem effects of their declines.Methodology/Principal FindingsWe satellite-tagged an apex predator (bull sharks, Carcharhinus leucas) and a sympatric mesopredator (Atlantic tarpon, Megalops atlanticus) in southern Florida waters to describe their habitat use, abundance and movement patterns. We asked four questions: (1) How do the seasonal abundance patterns of bull sharks and tarpon compare? (2) How do the movement patterns of bull sharks and tarpon compare, and what proportion of time do their respective primary ranges overlap? (3) Do tarpon movement patterns (e.g., straight versus convoluted paths) and/or their rates of movement (ROM) differ in areas of low versus high bull shark abundance? and (4) Can any general conclusions be reached concerning whether tarpon may mitigate risk of predation by sharks when they are in areas of high bull shark abundance?Conclusions/SignificanceDespite similarities in diet, bull sharks and tarpon showed little overlap in habitat use. Bull shark abundance was high year-round, but peaked in winter; while tarpon abundance and fishery catches were highest in late spring. However, presence of the largest sharks (>230 cm) coincided with peak tarpon abundance. When moving over deep open waters (areas of high shark abundance and high food availability) tarpon maintained relatively high ROM in directed lines until reaching shallow structurally-complex areas. At such locations, tarpon exhibited slow tortuous movements over relatively long time periods indicative of foraging. Tarpon periodically concentrated up rivers, where tracked bull sharks were absent. We propose that tarpon trade-off energetic costs of both food assimilation and osmoregulation to reduce predation risk by bull sharks.

Long‐term impacts of introduced flathead catfish on native ictalurids in a north Florida, USA, river

AbstractIntroduction of flathead catfish, Pylodictis olivaris (Rafinesque), in waters of the USA has been widespread and often with negative impacts. Flathead catfish have been collected in Florida waters since the 1980s, and this study documents their impact on native fishes shortly after establishment. Four sites in the Choctawhatchee River, Florida, were sampled from 1997 to 2011, a time period spanning several years before and after the presence of flathead catfish at all sites. Flathead catfish expanded more than 91 river km in 2 years. The population increased rapidly and became the numerically dominant ictalurid at each site within 3 years of first detection at the site. Concurrent with the increases in flathead catfish was the precipitous decline of the native spotted bullhead, Ameiurus serracanthus (Yerger &amp; Relyea). Electric fishing catch rates of flathead catfish significantly increased (P &lt; 0.03) over time at all sites, while spotted bullhead catch rates significantly declined (P &lt; 0.03) at three of four sites. Catch rates of flathead catfish and spotted bullhead were negatively correlated at all but the last site to be colonised by flathead catfish. This study provides evidence that introduced flathead catfish can quickly and significantly impact native ictalurids.

Survival of Red Grouper (&lt;I&gt;Epinephalus Morio&lt;/I&gt;) and Red Snapper (&lt;I&gt;Lutjanus Campechanus&lt;/I&gt;) Caught on J-Hooks and Circle Hooks in the Florida Recreational and Recreational-for-Hire Fisheries

We documented survival of released sublegal red grouper, Epinephalus morio (valenciennes, 1828), and red snapper, lutjanus campechanus (poey, 1868), caught on circle and j-hooks by recreational anglers in florida waters. Immediate hook mortality was 20.0% for red grouper and 49.1% for red snapper. Delayed (5 d) hook mortality from blood loss of j-hook nicked internal organs differed between red grouper (7%) and red snapper (29%). Delayed mortality from starvation was observed for five emaciated red snapper with severed esophagi from prior hook injuries. Different survival rates were correlated with feeding behavior, jaw morphology, and prey residence time. Mean (±Sd) prey residence time in the mouth was significantly longer for red grouper (6.62 ± 0.42 s) than red snapper (3.73 ± 0.29 s) possibly resulting in more red grouper being mouth hooked than red snapper, which were more likely to swallow bait and become gut hooked. Jaw morphology and feeding behavior may predict release survival for other species. Tag recapture rates used as a surrogate for survival were significantly higher for tagged red grouper initially caught on circle hooks (14.0%, n = 121 recaptures; 863 tagged) than on j-hooks (7.3%, n = 287 recaptures; 3935 tagged). Conversely, recapture rates were significantly higher for red snapper initially caught on j-hooks (12.5%, n = 269 recaptures; 2145 tagged) than circle hooks (8.1%, n = 258 recaptures; 3172 tagged). Mandatory regulations implementing the use of circle hooks when targeting all reef fish species may not provide the intended conservation benefits.

Hydrilla Management in Florida Lakes

Hydrilla is the most aggressive invasive plant in Florida waters. It can provide some benefits to fish and wildlife at low levels of coverage, but it also can have major detrimental impacts to water uses, causing substantial economic and environmental hardships. This 6-page fact sheet was written by Stacia A. Hetrick and Ken A. Langeland, and published by the UF Department of Agronomy, March 2012. SS-AGR-361/AG370: Hydrilla Management in Florida Lakes (ufl.edu)

An Approach to Developing Numeric Water Quality Criteria for Coastal Waters Using the SeaWiFS Satellite Data Record

Human activities on land increase nutrient loads to coastal waters, which can increase phytoplankton production and biomass and associated ecological impacts. Numeric nutrient water quality standards are needed to protect coastal waters from eutrophication impacts. The Environmental Protection Agency determined that numeric nutrient criteria were necessary to protect designated uses of Florida’s waters. The objective of this study was to evaluate a reference condition approach for developing numeric water quality criteria for coastal waters, using data from Florida. Florida’s coastal waters have not been monitored comprehensively via field sampling to support numeric criteria development. However, satellite remote sensing had the potential to provide adequate data. Spatial and temporal measures of SeaWiFS OC4 chlorophyll-a (ChlRS-a, mg m–3) were resolved across Florida’s coastal waters between 1997 and 2010 and compared with in situ measurements. Statistical distributions of ChlRS-a were evaluated to determine a quantitative reference baseline. A binomial approach was implemented to consider how new data could be assessed against the criteria. The proposed satellite remote sensing approach to derive numeric criteria may be generally applicable to other coastal waters.

Species Diversity of Shallow Water Zoanthids (Cnidaria: Anthozoa: Hexacorallia) in Florida

Shallow water zooxanthellate zoanthids are a common component of the coral reef ecosystems of the Caribbean. Despite this, their species diversity remains poorly understood. In this study, collectedPalythoa, Zoanthus, Isaurus, andTerrazoanthusspecimens from the waters of Florida were phylogenetically examined to obtain a better understanding of zoanthid species diversity in the Caribbean. Surprisingly, the results from analyses utilizing three DNA markers (mitochondrial 16S ribosomal DNA, cytochrome oxidase subunit I, and the internal transcribed spacer of ribosomal DNA) showed the presence of at least eleven species, of which up to four appear undescribed. Additionally, the presence of the genusTerrazoanthusin the Caribbean was confirmed for the first time. Attempts to match phylogenetic species or clades with original literature were hampered by vague and short original descriptions, and it is clear that for AtlanticPalythoaandZoanthusspecies an in-depth and multidisciplinary investigation is needed to reconcile recent phylogenetic results such as in this study with traditional taxonomy. Furthermore, most shallow water zoanthid species from Florida were observed to have close, sister-species relationships with previously investigated species in the Pacific Ocean. These results indicate that many brachycnemic zoanthid species likely had a Caribbean-Pacific distribution until the formation of the Isthmus of Panama. However, due to inadvertent redescriptions, overall species diversity in these two common genera is likely much lower than literature indicates.

Biology, ecology and bloom dynamics of the toxic marine dinoflagellate Pyrodinium bahamense

It has been 40 years since the first recorded toxic bloom of Pyrodinium bahamense occurred in Papua New Guinea in 1972. Subsequently this species has increased in importance as a paralytic shellfish poisoning toxin (PSTs) producer in several regions of the world, especially in the Indo-west Pacific. P. bahamense is a thecate tropical/subtropical euryhaline dinoflagellate. Available data indicate that it forms blooms only in waters of 20 psu or higher salinity and at temperatures above 20 °C. It is monospecies with two varieties, namely var. compressum and var. bahamense. For many years it was widely accepted that only var. compressum is toxic and is limited to the tropical Pacific while var. bahamense is nontoxic and is limited to the tropical Atlantic. It is now known, however, that there are at least two locations where the varieties co-occur and it has also been proven that var. bahamense in Florida waters also produce PST. P. bahamense has a life cycle typical of many dinoflagellates. It has a heterothallic sexual cycle that produces a large spiny spherical resting cyst. The toxicity profile of P. bahamense is also very simple with most isolates producing only dc-STX, STX, neoSTX, B1 and B2 toxins. Further studies are needed in order to resolve the varietal status of the species and also to understand the environmental factors that determine its toxicity and bloom dynamics.