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The Role Of Backreef Soundscapes And Their Spatial Structure For Recruitment Of Tropical Marine Larvae, Emily R. Anderson

Biological Sciences Theses & Dissertations

Underwater sound is a cue used by many marine larvae to orient to coastal habitats including backreef, sponge-dominated hardbottom habitat in the Florida Keys (Florida, USA) – a particularly “noisy” coastal habitat. However, the distance over which acoustic cues are attractive to settlement-stage larvae - is generally unknown. I examined this phenomenon in a region of the Florida Keys where mass sponge die-offs have diminished both underwater soundscapes and larval settlement. The absence of pronounced hardbottom-associated sound over such a large area allowed me to experimentally test in situ the response of fish and invertebrate larvae to broadcasted sounds at …

Response Of Fish And Invertebrate Larvae To Backreef Sounds At Varying Distances: Implications For Habitat Restoration, Emily R. Anderson, Jack Butler, Mark J. Butler

Biological Sciences Faculty Publications

Underwater sound is used by many marine larvae to orient to coastal habitats including backreef, sponge-dominated hardbottom habitat in the Florida Keys (FL, United States)—a particularly “noisy” coastal habitat. However, the distance over which acoustic cues are attractive to settlement-stage larvae is generally unknown. We examined this phenomenon in a region of the Florida Keys where mass sponge die-offs have diminished both underwater soundscapes and larval settlement. The absence of pronounced hardbottom-associated sound over such a large area allowed us to experimentally test in situ the response of fish and invertebrate larvae to broadcasted sounds at different distances from their …

The Effect Of Parental Size On Spermatophore Production, Egg Quality, Fertilization Success, And Larval Characteristics In The Caribbean Spiny Lobster, Panulirus Argus, Mark J. Butler Iv, Alison Macdiarmid, Gaya Gnanalingam

Biological Sciences Faculty Publications

The average size of spiny lobsters (Decapoda; Palinuridae) has decreased worldwide over the past few decades. Market forces coupled with minimum size limits compel fishers to target the largest individuals. Males are targeted disproportionately as a consequence of sexual dimorphism in spiny lobster size (i.e. males grow larger than females) and because of protections for ovigerous females. Therefore, overexploitation of males has led to sperm limitation in several decapod populations with serious repercussions for reproductive success. In the Caribbean spiny lobster, Panulirus argus, little is known about the effect of reduced male size on fertilization success or the role …

Modeling The Dispersal Of Eastern Oyster (Crassostrea Virginica) Larvae In Delaware Bay, Diego A. Narvaez, John M. Klinck, Eric N. Powell, Eileen E. Hofmann, John Wilkin, Dale B. Haidvogel

CCPO Publications

The interactions of circulation and growth processes in determining the horizontal distribution of eastern oyster (Crassostrea virginica) larvae in the Delaware Bay estuary were investigated with a coupled circulation-individual-based larvae model that used environmental conditions from the spawning seasons (mid-June to mid-September) of 1984, 1985, 1986, 2000, and 2001. Particles, representing oyster larvae, were released at five-day intervals from areas in Delaware Bay that correspond to natural oyster reefs. The simulated larval development time was used to estimate potential larval success, determined by the percent of larvae that successfully reached settlement size (330 µm) within the planktonic larval …

Spatial Variation In Otolith Chemistry Of Atlantic Croaker Larvae In The Mid-Atlantic Bight, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones

OES Faculty Publications

Larval Atlantic croaker Micropogonias undulatus (1 to 7 mm in standard length) were collected on the east coast of the United States from North Carolina to Delaware during 2000. We defined 3 water-mass boundaries for potential groups of spawning Atlantic croaker using temperature and salinity measured at each sampling station. We tested the hypothesis that distinct otolith chemistries existed among 3 groups of larval Atlantic croaker collected from these water masses using solution-based inductively coupled plasma-mass spectrometry. Multivariate analysis of variance indicated that otolith chemistry differed significantly among water masses. Using a quadratic discriminant function, we were able to correctly …

Influence Of Short-Term Variations In Food On Survival Of Crassotrea Gigas Larvae: A Modeling Study, Eric N. Powell, Eleanor A, Bochenek, John M. Klinck, Eileen E. Hofmann

OES Faculty Publications

A biochemically-based model was developed to simulate the growth, development, and metamorphosis of larvae of the Pacific oyster, Crassostrea gigas. The model defines larvae in terms of their protein, lipid, carbohydrate, and ash content and includes variation in growth efficiency and egg quality to better simulate cohort population dynamics. Changes in tissue composition occur as the larva grows and in response to the biochemical composition of the food. The premise behind this modeling study was that certain periods of larval life are more critical than others with respect to the availability of food and that food quality is as …

The Effect Of A Predator Gradient On Female Oviposition Site Selection And Larval Performance, Josef F. Rieger

Biological Sciences Theses & Dissertations

Patterns of larval amphibian distribution and abundance have historically been ascribed to direct predation. However, adult oviposition site selection is an alternative mechanism that can produce identical patterns and significantly influence community assembly. Although such behavioral habitat selection has been documented in several amphibian species whose larvae lack particular anti-predator defenses, the sensitivity of adult amphibians in detecting predator cues and avoiding these habitats has not yet been determined. If larval survivorship is greatly reduced in sites containing predatory fish, selection to detect and avoid habitats with low fish densities should be strong. I conducted three experiments which, (1) evaluated …

Comparison Of Larval Myomere Counts Among Species Of Nocomis In Virginia (Actinopterygii: Cyprinidae), Terre D. Green, Eugene G. Maurakis

Virginia Journal of Science

Larval myomere counts of Nocomis platyrhynchus were made using a dissecting light microscope equipped with polarizing filters, and then compared to those of the three other species of Nocomis (Nocomis leptocephalus, Nocomis micropogon, and Nocomis raneyi) found in Virginia. Average preanal myomere counts for N. platyrhynchus (26.9) were significantly different from those of the other three species (N. raneyi =28.7; N. micropogon =26.0; and N. leptocephalus =25.9). This is especially important as larvae of N. leptocephalus, the only other species of Nocomis syntopic with N. platyrhynchus in the upper New River drainage, can now …

A Modeling Study Of The Effects Of Size- And Depth-Dependent Predation On Larval Survival, Margaret M. Dekshenieks, Eileen E. Hofmann, John M. Klinck, Eric N. Powell

CCPO Publications

The form of the predation pressure experienced by larval stages of marine invertebrates is largely unknown. However, it is believed that the type, timing and rate of larval predation are critical in determining recruitment to adult populations. In this study, a time and depth-dependent model of the growth and behavior of larvae of the Eastern oyster, Crassostrea virginica, was used to investigate the effects of different forms of size-and depth-dependent predation on larval survivorship. The simulated larval survival for a cohort experiencing size-dependent predation showed that the greatest percent of the cohort survived to competent settlement size when the …

The Growth And Bioenergetics Of Callinectes Sapidus Larvae And The Effects Of Diet Quality On Larval Physiology, James J. Pletl

OES Theses and Dissertations

Food quality, especially ω3 polyunsaturated fatty acids (PUFA), can affect the physiology and metabolic efficiency of larvae of the blue crab, Callinectes sapidus. These affects may correlate with success in development and juvenile recruitment.

Larvae were exposed to two diets differing quantitatively in ω3 PUFA and respiration, excretion, growth, and feeding rates were measured for each larval stage and the megalopal stage. The energy partitioned to molts and specific dynamic action was also measured. T

he ω3 PUFA enriched diet resulted in a lower respiration rate when compared to the unsupplemented diet, but there was little differences in excretion …

Investigations Of The Trophic Relationships, Feeding Ecology And Feeding Behavior Of Larval Spot, Leiostomus Xanthurus Lacepede, And Atlantic Croaker, Micropogonias Undulatus (Linnaeus) (Pisces:Sciaenidae), Dirk Edward Peterson

Biological Sciences Theses & Dissertations

The feeding ecology of preflexion and flexion-postflexion spot (Leiostomus xanthurus) and Atlantic croaker (Micropogonias undulatus) larvae was evaluated and compared. Nutritional condition of spot larvae from the Gulf of Mexico was high, with no larvae classified as starving. This was probably due to an inability to sample starving larvae at sea because of predation pressure or was indicative of favorable feeding conditions and an absence of starvation in the collection area. In spite of morphological similarities between the species, significant differences in body shape existed.

The diets of the two species converged with age and interspecific dietary overlap was relatively …

A Histological Investigation Of The Larval Mandibular Organ In The Mud Crab Rhithropanopeus Harrisii (Gould) (Crustacea Decapoda Xanthidae), Lore Lynn Hantske

OES Theses and Dissertations

Mandibular organs of the mud crab, Rhithropanopeus harrisii (Gould) were histologically located and followed throughout the larval cycle to determine their role in metamorphosis. Specimens from each day of the four larval stages and the megalopa stage were embedded in paraffin, sectioned at 8 μm, stained and observed under the microscope for the mandibular organs. The organs were located in the mandibular area of second, third and fourth stage larvae. The organs were probably present in the first stage zoeae and in the megalopa stage, although the

techniques of the study were not sensitive enough to observe them. The …

The Seasonality Of Occurrence Of Larval And Juvenile Sciaenids In A Virginia Seaside Estuary, James Howard Cowan Jr.

Biological Sciences Theses & Dissertations

The seasonality of occurrence and relative abundance of larval and juvenile fishes, particularly members of the family Sciaenidae, from a Virginia seaside estuary were determined from ichthyoplankton and trawl collections made from March 1979 to March 1980.

The larvae of 20 species distributed among 15 families were identified from the ichthyoplankton. Larvae of the bay anchovy, Anchoa mitchilli, and the Atlantic silverside, Menidia menidia, dominated the samples and made up 57 and 34%, respectively, of all larvae collected. Peak occurrence began in May and continued through August. Fish larvae were present in the study area all year.

Twenty-eight …

The Effects Of Elevated Calcium Chloride And Magnesium Chloride Levels On Larval Growth And Survival Of Macrobrachium Rosenbergii (De Man) (Decapoda Palaemonidae) Reared In The Laboratory, James Thomas Michaels Ii

OES Theses and Dissertations

The effects of elevated CaCl₂ , MgCl₂ , combination CaCl₂ and MgCl₂ concentrations and their associated ionic strengths on larval growth and survival of the freshwater prawn, Macrobrachium rosenbergii were investigated in the laboratory. Larvae were reared in diluted seawater of 15 parts per thousand salinity with elevated calcium concentrations of 330 parts per million and elevated magnesium concentrations of 1275 parts per million. Control larvae were also reared with elevated NaCl concentrations to duplicate the ionic strength increases of the combination CaCl₂ - MgCl₂ test solution which had the highest ionic strength. A …

Aspects Of Larval Ecology Of Squilla Empusa (Crustacea, Stomatopoda) In Chesapeake Bay, Steven G. Morgan

OES Faculty Publications

Larvae of Squilla empusa were collected from the plankton and were laboratory-reared in 16 combinations of temperature and salinity to determine their tolerances. Larvae survived longer and molted more frequently when reared at 25%, and 20° or 25° C, which corresponds to the natural conditions of Chesapeake Bay when the larvae were collected.

A 2 year planktonic survey conducted in the lower region of the bay by the Virginia Institute of Marine Sciences was compared with a survey made at the bay mouth in 1976. The seasonal occurrence of Squilla empusa larvae extended from the last week of July until …

The Spatial And Temporal Distribution Of Fish Eggs And Larvae In Hempstead Bay Estuary, Joseph Adelard Lessard

OES Theses and Dissertations

The ichthyoplankton of Hempstead Bay estuary was sampled from December 1972 to mid March 1974. Eleven stations were sampled by towing a 0.5 meter diameter plankton net. Eggs were most abundant during June and July with an average concentration calculated to be above 5,500/100m³. Egg densities were the lowest during the fall and winter. Larvae were most frequently taken from March through July with densities varying greatly among the samples. The eggs of Brevoortia tyrannus, Anchoa mitchilli, Tautoga onitis, Tautogolabrus adspersus, and Scophthalmus aguosus and the larvae of Menidia menidia, Ammodvtes hexapterus and Pseudopleuronectes americanus constituted most …

Description Of The Larval Development Of Squilla Empusa Say (Crustacea Stomatopoda) With Aspects Of Larval Ecology In Chesapeake Bay, Steven Gaines Morgan

OES Theses and Dissertations

Larvae of Sguilla empusa were collected from the plankton and were reared in the laboratory to describe the pelagic larval development and the postlarval stage. Nine pelagic stages are passed through before the postlarval stage is attained.

The larvae reared for descriptive purposes were subjected to sixteen combinations of temperature and salinity to determine their tolerance to the two parameters. Larvae survived longer and molted more frequently when reared at 25°/oo and 20°C or 25°C, which corresponds to the natural conditions of the Chesapeake Bay when the larvae were collected.

A three year planktonic survey conducted in the lower region …

A Baseline Study On The Possible Mechanisms Of Larval Stomatopod Distribution On The Carolina Shelf, Carl Robert Berman Jr.

OES Theses and Dissertations

The South Carolina Marine Resources Institute provided the author with 198 station samples containing 2,193 stomatopod larvae. These larvae had been collected during ichthyoplankton Bongo tows on five separate cruises aboard the Institute's vessel R/V DOLPHIN (February, 1972 to January, 1975). The larvae were examined microscopically and divided into early, middle, and late stages according to known growth criteria. The larval distribution was plotted geographically, by seasons, and larval density (larvae/m3) was graphed against distance offshore. Using these data, together with the circulation characteristics on the Carolina Shelf, significant distributional data appeared which supported the hypothesis that the stomatopod population …