This project reviews the basic chemical and geographical features of the ocean, biological classification of marine life, background of the ocean's flora and fauna, and the ocean's environment. These facts are presented through an underwater documentary filmed at various sites along Southern California's coast and complemented with lesson plans designed for grades K - 4.

Bibliography: pages 100-108. / The snoek Thyrsites atun is an important fish predator in the southern Benguela region. It is exploited by both a handline and a demersal fishery. A survey of the Cape line fishery revealed that snoek line fishing effort is changing from the traditional harbour-based line-boat to the nomadic ski-boat. It was widely claimed that snoek catches are declining and that migration patterns are changing. Snoek constitute a by-catch of the hake-directed demersal fishery but nevertheless are seasonally important. The principle prey of snoek caught by handline off the Cape Peninsula were anchovy and mantis shrimp. Snoek caught in midwater trawls offshore were feeding primarily on anchovy, with pilchard, euphausiids and amphipods also important. Snoek trawled demersally had a more diverse diet, dominated by redeye roundberring, lightfish, lanternfish, hake, buttersnoek and euphausiids. Snoek were caught in the demersal environment throughout daylight hours, but may come off the bottom at night. The small degree of overlap between the diet of snoek caught demersally offshore and that of snoek caught in the pelagic zone, both inshore and offshore, indicates that snoek do not seem to move extensively on a diurnal basis between the two zones. Over the period 1970 to 1985 availability of snoek to the handline fishery was strongly seasonal, with catches peaking from May to July, although the traditional winter snoek run is a declining phenomenon along the South African coast. At Dassen Island, for which catch data have only been available since 1981, peak months were from November to January. The snoek seems to move offshore from July and is trawled demersally until September. The presence of snoek larvae offshore between June and September indicates an offshore spawning migration. With the exception of the summer presence in the region of Dassen Island, snoek appear to be present in the southern Benguela region between April and September. Handline catches of snoek have declined markedly since 1978, but demersal catches have remained more stable.

The toxin-producing harmful algal bloom (HAB) species Alexandrium monilatum has long been associated with finfish and shellfish mortalities in the Gulf of Mexico. In the summer of 2007, A. monilatum re-emerged as a bloom-forming species in the Chesapeake Bay. Over the last decade, late summer blooms of A. monilatum have been expanding in range in the lower Chesapeake Bay and have reached record-high densities, particularly in the lower York River. This dinoflagellate species overwinters in the sediments as a resting cyst, and upon excystment under suitable environmental conditions produces blooms the following summer. The research presented here includes the first mapping and quantification of resting cysts of A. monilatum in surface sediments in the Chesapeake Bay using quantitative real-time polymerase chain reaction (qPCR) assays. A systematic grid sampling design was employed to collect pre-bloom sediments in the southwestern portion of the Chesapeake Bay each year from 2014-2016. Cysts were widespread in the bottom sediments and sediment cyst density increased from 2014-2016, reaching as high as 90,000 cysts/cc in the York River channel. A multiple linear regression was used to model cyst density using environmental parameters. Sediment type was a strong predictor of cyst density, with higher cyst densities found at sites with more fine sediments (silts and clays). Laboratory HAB toxicity bioassay methods were used to investigate potential adverse health impacts of A. monilatum on adult triploid eastern oysters, Crassostrea virginica. Oyster behavior and mortality were monitored and routine paraffin histology was performed to analyze tissue damage. Oysters did not exhibit mortality or tissue damage in a 48-hour fed toxicity bioassay. However, a 96-hour unfed toxicity bioassay led to 67% mortality, and erosion of the gill and mantle epithelial tissues in 94% of oysters exposed to A. monilatum (live cell or lysate). In the summer of 2015, oysters were deployed in the lower York River to assess effects of exposure before, during, and after a natural A. monilatum bloom. A subsample of six live oysters was collected weekly for two months and processed for histology. There was no mortality of deployed oysters, but minor epithelial erosion of the mantle was seen in half of the oysters sampled during the peak of the A. monilatum bloom from early to mid-August. Field and laboratory results showed that C. virginica did occasionally consume A. monilatum, and exposure of C. virginica to live A. monilatum or lysate could lead to epithelial erosion of external tissues and mortality. It is clear from the findings of this research that A. monilatum has established itself in the York River region of the Chesapeake Bay and that at least under laboratory conditions, persistent exposure to A. monilatum (live or lysate) can have serious potential health impacts on adult oysters.

N2 fixation rates for several Virginia salt marshes were determined using in situ acetylene-reduction assays. A control and a chronically polluted oil marsh of the mesohaline Mobjack Bay area were sampled over a 1975-76 annual cycle. N2 fixation occurred in all transects which extended from upper mudflat to the Spartina patens zone. An isolated blue-green algal mat exhibited some of the highest N2 fixation rates. Intertidal sediment N2 fixation was patchy, both spatially and seasonally. However average rates (91.45 μg N/m2/h) compared to the estimated N requirement of the graminoid vegetation indicated a significant contribution to the N budget. Vegetation associated nitrogen fixation yielded higher average rates. N2 fixation rates for Wachapreague high salinity and Yorktown relic low salinity marshes were similar to the mesohaline marshes although blue-green algae fixation seemed to be more significant. The seasonal pattern of mesohaline marsh N2 fixation was positively related to temperature. Light-dark and anaerobic-aerobic experiments support the hypothesis that heterotrophic bacteria are the predominant N2 fixers and that availability of oxidizable substrates contribute to the seasonal pattern. Chronic oil treatment showed little effect on fixation rates with the possible exception of median tidal elevation sediments where summer rates were considerably higher than those of the control. This dissertation is from the Joint Program Degree from the College of William & Mary and University of Virginia and awarded by the University of Virginia.

Foraminiferal faunas in marshes and distributary channels of the James River estuary, Virginia, disclose several facies. The channel facies, primarily Ammobaculites crassus, and A. sp. A, typical of estuaries in Chesapeake Bay and other brackish areas are readily distinguishable freom the march facies. Marshes are divisible laterally by changes in the relative proportions of marsh species such as Miliammina fusca, Ammoastuta salsa, and Haplophragmoides hancocki.Changes along the longitudinal estuarine salinity gradient are discernable in both tidal creeks and marsh. Channels exhibit a longitudinal gradient from a freshwater thecamoebinid facies through an upper and mid-estuarine Ammobaculites facies to a higher salinity Elphidium assemblage. Marshes are divisible into thecamoebinid, Ammoastuta-Miliammina and Miliammina zones. Macroscopic marsh floral zones along the estuary exhibit changes which are similar to, but do not mirror, changes in foraminiferal facies. Both distributions are responses to salinity and elevation above Mean Low Water. Paleocological inferences are drawn from data on distributions of marsh microfaunas. This dissertation is from the Joint Program Degree from the College of William & Mary and University of Virginia and awarded by the University of Virginia.

The main purpose of this study is to describe the population ecology of eight species of harpacticoid copepods over a period of one year with emphasis on the effects of physical interactions and biotic factors on these populations. The species were: Amphiascopsis sintus (Claus) 1866, Stenhelia (D.) oblonga Lang, 1965, Heterolaphote variables Lang, 1965, Ectinosoma melaniceps Boek ? var. T. Scott, 1902, Paralophonte subterraneas Lang, 1965, Tisbe furcata (Baird) 1837, Diasaccus spinatus Cambell, 1929 and Parathelestris bulbiseta Cambell?.

Abalone farms are becoming more common along the coast of South Africa. The effects these farms are having on the coastal habitats they occupy are becoming of increasing concern due to the possible negative effects of the effluent discharged from the farm. This study was conducted along the coast of Jacobsbaai (32°58'22.09" Sand 17°53'10.56" E) and Mauritzbaai (32°58'50.75"S and 17°52'59.44"E) near Saldanha on the South African west coast, situated approximately 120 Km from Cape Town. The aim of this study is to determine if the outflow of effluent from the Jacobsbaai Sea Products (pty) Ltd, abalone farm in Jacobsbaai can be traced using stable carbon and nitrogen isotopes. Kelp (Ecklonia maxima) and blue mussels (Mytilus galloprovincialis) along the coast near the farm (in Jacobsbaai) were collected from 8 sites and used as tracers of the farms effluent. A ninth site was sample in another bay (Mauritzbaai) which functioned as our control. We hypothesised that if the kelp and mussels are taking up the nitrogen and carbon from the farm, the amount of nitrogen and carbon taken up would decrease with decreasing distance from the effluent outfall. Using this we could map the geographic distribution of the abalone effluent alone the coast to measure the extent of eutrophication due to abalone effluent. Our results suggest that the effluent from the farm is having a localized effect on both Ecklonia maxima and Mytilus galloprovincialis.

No description available.

The identification and delineation of nursery areas and areas of aggregation of north Atlantic sharks has been identified as an important information need for future management efforts. The objectives of this project were to use a fishery-independent method to study the overwintering area of juvenile sandbar sharks, to spatially delineate the Eastern Shore nursery area, and to examine movement patterns and space use within this nursery area. Data from 21 satellite transmitters attached to large juvenile sandbar sharks revealed that these sharks primarily occurred off the outer banks of North Carolina, at deeper depths and colder water temperatures during the overwintering period (after November 1). The data from this project support the size and scope of the closed area currently enacted by the Fishery Management Plan. The Eastern Shore of Virginia was found to be an important primary and secondary nursery area for this population of sandbar sharks. Within this nursery area sharks were most concentrated in Great Machipongo Inlet. Abundance of juvenile sandbar sharks was positively correlated to distance from the inlet and water temperature. Smaller juvenile sharks were more concentrated farther from the inlets and were more prevalent in the southern inlets. Juvenile sandbar shark movements were studied using passive acoustic telemetry. Juveniles tended to spend significantly more time farther from the inlets and their space use was positively correlated to time of day with a greater proportion of time spent in the acoustic array during the night time hours. Tidal currents were positively correlated with small scale movements but were unrelated to overall space use. The sharks tracked returned or remained within the array to a greater extent than would be predicted by random movements alone indicating these animals have some site attachment to these areas. Smaller sharks remained within the array area to a greater extent than larger sharks indicating they likely have smaller activity spaces. This study emphasizes the importance of both the Eastern Shore of Virginia nursery area and the overwintering area that occurs off the central coast of North Carolina as essential habitat for the north Atlantic population of sandbar sharks.

Immature foraging sea turtles occupy Chesapeake Bay, Virginia annually from May through November. Telemetry was used to monitor the movements and behavior of loggerhead, Caretta caretta, and Kemp's ridley, Lepidochelys kempi, turtles during 1981-1985. Both species utilized the estuary for summer foraging, but exhibited habitat-preference and behavioral differences that amounted to resource partitioning between the species. Loggerheads oriented towards major river outflows and tended to move along channel sides with the tidal flow while ridleys occupied shallower foraging areas and did not range as far with the tide. Strong site tenacity was displayed by both species once foraging areas were established. Differences were apparent in respiratory behavior; ridleys remained on the surface for longer and underwater for shorter periods than loggerheads. Ridleys had a tendency to stay on the surface longer during daylight than night hours, whereas loggerheads surfaced and submerged longer during night than daylight. Estimates of daylight respiration behavior of loggerheads (surface to dive time ratio of 1:17) were used to adjust estimates of population size. Replicated aerial surveys for loggerheads yielded an unadjusted mean population over 1982-1985 of 423. A respiration adjustment factor which accounts for turtles unseen because they are below the surface (17 turtles below the surface for every one seen at the surface) yielded an average annual estimate of 7905. Reported mortality is a small percentage (1.4) of the adjusted population estimate. Mark-recapture, aerial survey and biotelemetric techniques were used in 1980 and 1982-1985 to elucidate migrations of loggerheads and ridleys which are incapable of overwintering in Chesapeake Bay. For both species, the period of residence in the Bay was correlated with water temperature. Migrations to the Bay were linked to vernal warming; the heaviest concentrations of turtles were found south of the 18 C isotherm. Fall migration was linked less strongly with declining water temperature and appeared to be related to the onset of winter storms. Migrating loggerheads remained nearshore in southerly currents in the fall. Contact with most telemetered loggerheads was broken in the vicinity of Cape Hatteras, North Carolina. A satellite-tracked loggerhead spent two months in the vicinity of the Gulf Stream offshore before contact was broken.