Life Sciences Commons^™

Seasonal Abundance Of The Nudibranch Dondice Jupiteriensis On The Colonial Hydroid Eudendrium Carneum, Erika Molina, Daniela Gutierrez-Andrade, Samantha Schlegel, Julia Piper, Louis J. Ambrosio, Michael L. Middlebrooks

Gulf and Caribbean Research

Benthic colonial hydroids often serve as a host to a large variety of invertebrate taxa. The colonial hydroid Eudendrium carneum Clarke, 1882 is host to a variety of epifauna, including the recently described nudibranch Dondice jupiteriensis García—Méndez & Valdés, 2022. Like many species of heterobranch sea slugs, little is known about the natural history and population biology of D. jupiteriensis. Here we describe a year—long study recording the population density and size structure of D. jupiteriensis on E. carneum colonies in Tampa Bay, FL USA. We found that the D. jupiteriensis population persists year—round but is the densest during …

Ocean Quahog (Arctica Islandica) Population Dynamics: Sex-Based Demographics And Regional Comparisons In The Northwest Atlantic, Kathleen M. Hemeon

Dissertations

Arctica islandica (ocean quahog) is the longest-lived bivalve on Earth. Individuals on the deep continental shelf of the Mid-Atlantic (US) can survive for centuries, and when found in the colder, boreal waters of Iceland, ages over 500 years can be reached. The ocean quahog is important in the US, yet very little is known about the resiliency of the ocean quahog stock to fishing activity, and ocean quahog recruitment patterns over time. To quantify and constrain age-reader error prior to age analysis, a triple-method error protocol was developed for A. islandica that included age-reader bias, precision, and error frequency. The …

Distribution, Maturity, Age And Growth Of Gray Snapper (Lutjanus Griseus) In The Northwestern Gulf Of Mexico, Joel Anderson, Dusty Mcdonald, Ethan Getz, Roberta Weixelman, Faye Grubbs, Jason Ferguson

Gulf and Caribbean Research

Recent population expansion of Gray Snapper, Lutjanus griseus, in the northern Gulf of Mexico is driving increasing catch in the recreational fishery in Texas. We assessed long—term trends in distribution and abundance of Gray Snapper in Texas using fishery—dependent and fishery—independent data collected by the Texas Parks and Wildlife Department in the years 1980 — 2019. Boosted regression trees (BRT) were used to evaluate factors (water quality, season, depth, bay and inlet distance) driving Gray Snapper presence in fishery—independent samples of juveniles (seines) and subadults (gill nets) found in estuaries. Estuarine Gray Snapper were subsequently sampled from gill nets, …

Temperature Stress And Disease Drives The Extirpation Of The Threatened Pillar Coral, Dendrogyra Cylindrus, In Southeast Florida, Nicholas P. Jones, Lystina Kabay, Kathleen Semon Lunz, David S. Gilliam

Marine & Environmental Sciences Faculty Articles

Rare species population dynamics can elucidate the resilience of an ecosystem. On coral reefs, climate change and local anthropogenic stressors are threatening stony coral persistence, increasing the need to assess vulnerable species locally. Here, we monitored the threatened pillar coral, Dendrogyra cylindrus, population in southeast Florida, USA, in relation to consecutive heat stress events in 2014 and 2015. In the fall of each year, D. cylindrus colonies bleached following intense thermal stress and by June 2020 all monitored colonies died from a white-syndrome type disease. This resulted in the ecological extinction of D. cylindrus in the Southeast Florida Coral …

Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter

FIU Electronic Theses and Dissertations

This research investigates the distribution and population structure of crustaceans, endemic to anchialine systems in the tropical western Atlantic focusing on cave-dwelling shrimp from the family Barbouriidae. Taxonomic and molecular tools (genetic and genomic) are utilized to examine population dynamics and the presence of phenotypic hypervariation (PhyV) of the critically endangered species Barbouria cubensis (von Martens, 1872). The presence of PhyV and its geographic distribution is investigated among anchialine populations of B. cubensis from 34 sites on Abaco, Eleuthera, and San Salvador, Bahamas. Examination of 54 informative morphological characters revealed PhyV present in nearly 90% (n=463) of specimens with no …

Density-Dependent Condition And Growth Of Invasive Lionfish In The Northern Gulf Of Mexico, Kristin A. Dahl, Morgan A. Edwards, William F. Patterson Iii

C-IMAGE Publications

Absent natural population control, invasive red lionfish Pterois volitans (hereafter, lionfish) have reached record densities in the northern Gulf of Mexico (nGOM), though the role of density dependence on their population dynamics remains poorly understood. This study examined the effects of population density, sex, and habitat on lionfish condition (i.e. mass relative to total length) and size-at-age. Lionfish density was estimated with a remotely operated vehicle during 2010-2017 at a series of nGOM natural (n = 16) and artificial (n = 22) reefs, and individual lionfish (n = 3296) were sampled at additional reefs in the same system between 2013 …

Evaluating Recruitment Seasonality Of Red Abalone (Haliotis Rufescens) To Inform Fisheries Management And Conservation Policy, Leslie Christine Hart

Master's Theses

Recruitment, the addition of new individuals to a population, must be understood to make predictions about population growth of marine invertebrates. Red abalone (Haliotis rufescens) represent a former important commercial fishery in California, and until recently, supported a major recreational fishery. However, there have been statewide declines since the 1960s due to overfishing, disease, and climatic factors. Thus, understanding population dynamics to inform management and population restoration is critical. Recruitment dynamics of red abalone are poorly understood, with no prior knowledge of seasonal trends. To address this knowledge gap, I assessed monthly (July 2016-June 2017) and annual (2012-2016) …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

Genetic Variability Within Seagrass Of The North West Of Western Australia: Report Of Theme 5 - Project 5.2 Prepared For The Dredging Science Node, Kathryn Mcmahon, Udhi Hernawan, Kor-Jent Van Dijk, Michelle Waycott, Ed Biffin, Richard Evans, Paul Lavery

Research outputs 2014 to 2021

This study was the first of its kind to examine the patterns of genetic diversity in seagrasses in the Pilbara region of WA. Three species were assessed: Halophila ovalis (6 populations), Halodule uninervis (8 populations) andThalassia hemprichii (3 populations) at a range of spatial scales, within a meadow (centimetres−metres), among meadows at a local scale (2−60 km) and among meadows at a regional scale (up to 500 km). Due to the varied distribution of species all species across the same spatial scale and range of environments could not be sampled, so a nested approach was designed, with sites …

Natural Dynamics: Understanding Natural Dynamics Of Seagrasses Of The North West Of Western Australia. Report Of Theme 5 - Project 5.3 Prepared For The Dredging Science Node, Mat Vanderklift, Douglas Bearham, Mick Haywood, Hector Lozano-Montes, Roisin Mccallum, James Mclaughlin, Kathryn Mcmahon, Nick Mortimer, Paul Lavery

Research outputs 2014 to 2021

Relatively little is known of the spatial and temporal dynamics of seagrass meadows in the northwest of Western Australia, but such knowledge is needed when designing and evaluating studies that aim to detect potential dredging-related impacts on seagrass, and when making predictions about the likelihood of, and speed of recovery from such impacts. This study was undertaken to improve our understanding of the spatial and temporal patterns in seagrass composition, abundance and reproductive phenology in the Pilbara. We also characterised key environmental parameters, especially light, that influence seagrass survival and can be altered by dredging.

Aims

To improve our understanding …

Sustainable Whale-Watching For The Philippines: A Bioeconomic Model Of The Spinner Dolphin (Stenella Longirostris), Allison Jenny Santos

HCNSO Student Theses and Dissertations

Whale-watching provides economic opportunities worldwide and particularly proliferates in developing countries, such as the Philippines. The sustainability of whale-watching is increasingly debated as these activities also negatively impact cetaceans through changes in behavior, communication, habitat use, morbidity, mortality, and life-history parameters. This study evaluated the total annual cost, revenue, and profit of whale-watching operators in Bais, Philippines, and predicted the changes in the population for spinner dolphin Stenella longirostris with varying levels of whale-watching effort. Total revenue was 3,805,077 PHP ($92,478 USD) while total cost was 5,649,094 PHP ($137,294 USD) with a discount rate of ten percent. The total annual …

Population Dynamics Of The Little Gulper Shark (Centrophorus Uyato) And Community Analyses Of Elasmobranch Species In The Northern Gulf Of Mexico, Jacquelin Joye Hipes

USF Tampa Graduate Theses and Dissertations

In chapter 1 I describe the population dynamics of an understudied species of gulper shark, Centrophorus uyato (common name, the Little Gulper), found in the Northern Gulf of Mexico. Sharks in the family Centrophoridae are mid-sized, demersal fish, with seven species identified in North American waters. These deepwater species can be difficult to study due to the extreme depths at which they occur. During four longlining cruises from 2012-2014, 593 sharks were landed, predominantly in the Mississippi Canyon off the Louisiana coast. Mean depth of capture was 290 m. Supplementing these data are catch records for C. uyato from a …

Conus: First Comprehensive Conservation Red List Assessment Of A Marine Gastropod Mollusc Genus, Howard Peters, Bethan C. O'Leary, Julie P. Hawkins, Kent E. Carpenter, Callum M. Roberts

Biological Sciences Faculty Publications

Marine molluscs represent an estimated 23% of all extant marine taxa, but research into their conservation status has so far failed to reflect this importance, with minimal inclusion on the authoritative Red List of the International Union for the Conservation of Nature (IUCN). We assessed the status of all 632 valid species of the tropical marine gastropod mollusc, Conus (cone snails), using Red List standards and procedures to lay the groundwork for future decadal monitoring, one of the first fully comprehensive global assessments of a marine taxon. Three-quarters (75.6%) of species were not currently considered at risk of extinction owing …

Human Impact On Atolls Leads To Coral Loss And Community Homogenisation: A Modeling Study, Bernhard Riegl, Charles R. C. Sheppard, Samuel J. Purkis

Marine & Environmental Sciences Faculty Articles

We explore impacts on pristine atolls subjected to anthropogenic near-field (human habitation) and far-field (climate and environmental change) pressure. Using literature data of human impacts on reefs, we parameterize forecast models to evaluate trajectories in coral cover under impact scenarios that primarily act via recruitment and increased mortality of larger corals. From surveys across the Chagos, we investigate the regeneration dynamics of coral populations distant from human habitation after natural disturbances. Using a size-based mathematical model based on a time-series of coral community and population data from 1999–2006, we provide hind- and forecast data for coral population dynamics within lagoons …

Field Ecology Patterns Of High Latitude Coral Communities, Kristi A. Foster

HCNSO Student Theses and Dissertations

Some climate models predict that, within the next 30-50 years, sea surface temperatures (SSTs) will frequently exceed the current thermal tolerance of corals (Fitt et al. 2001; Hughes et al. 2003; Hoegh-Guldberg et al. 2007). A potential consequence is that mass coral bleaching may take place (i) during warm El Niño-Southern Oscillation (ENSO) events which are predicted to occur in some regions more frequently than the current 3-7 year periodicity (Hoegh-Guldberg 1999; Sheppard 2003) or (ii) perhaps as often as annually or biannually if corals and their symbionts are unable to acclimate to the higher SSTs (Donner et al. 2005, …

Distributions Of Sharks Across A Continental Shelf In The Northern Gulf Of Mexico, J. Marcus Drymon, Sean P. Powers, John Dindo, Brian Dzwonkowski, Terry A. Henwood

University Faculty and Staff Publications

Declines in shark populations have sparked researchers and fishery managers to investigate more prudent approaches to the conservation of these fish. As managers strive to improve data collection for stock assessment, fisheries-independent surveys have expanded to include data-deficient areas such as coastal regions. To that end, a catch series from a nearshore survey off Alabama was combined with data from a concurrent offshore survey with identical methodology to examine the depth use of sharks across the continental shelf (2–366 m). The combined data set contained 22 species of sharks collected from 1995 to 2008: 21 species in the offshore data …

Potential Effects Of Catastrophic Cyanobacteria Blooms On Caribbean Spiny Lobster Population Dynamics In Florida Bay Usa, Donald C. Behringer, Mark J. Butler Iv

Biological Sciences Faculty Publications

No abstract provided.

Abundance And Exploitation Rate Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay, Af Sharov, Jh Volstad, Gr Davis, Bk Davis, Rom Lipcius, Mm Montane

VIMS Articles

We estimated absolute abundance of the blue crab stock in Chesapeake Bay during winter from stratified random surveys conducted baywide from 1990 to 1999, using the swept-area method. We estimated catching efficiency of the survey gear from multiple depletion experiments to correct for temporal and vessel/area differences in catchability. The survey was conducted during the winter, when crabs are dormant and "buried" in the bottom. Analysis of crab carapace width (CW) frequency distributions revealed two size modes: CW less or equal 60 mm and CW greater than 60 mm, corresponding to age-0 (recruits) and age-1+ (one year and older), respectively. …

The Implications Of The Target-Area Hypothesis On The Population Dynamics Of The Spotted Spiny Lobster, Panulirus Guttatus, Denice N. Robertson

Biological Sciences Theses & Dissertations

The target-area hypothesis, based on the theory of island biogeography, predicts that larger islands are more effective at intercepting passive immigrants. Most marine invertebrates have meroplanktonic larvae and open population dynamics, so immigration to populations in isolated benthic habitats is primarily by pelagic larval recruits. Thus, recruitment to isolated habitat “islands” may be more continuous and predictable on large islands than on small ones. Consequently, populations on large islands should not only be larger than those on small islands, but should also have more evenly distributed size structures. These differences in size structure among populations in isolated habitats of differing …

Understanding The Success And Failure Of Oyster Populations: The Importance Of Sampled Variables And Sample Timing, Thomas M. Soniat, Eric N. Powell, Eileen E. Hofmann, John M. Klinck

CCPO Publications

One of the primary obstacles to understanding why some oyster populations are successful and others are not is the complex interaction of environmental variables with oyster physiology and with such population variables as the rates of recruitment and juvenile mortality. A numerical model is useful in investigating how population structure originates out of this complexity. We have monitored a suite of environmental conditions over an environmental gradient to document the importance of short time-scale variations in such variables as food supply, turbidity, and salinity. Then, using a coupled oyster disease population dynamics model, we examine the need for short rime-scale …

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 …

Factors Affecting The Recruitment Of Juvenile Caribbean Spiny Lobsters Dwelling In Macroalgae, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt

Biological Sciences Faculty Publications

In south Florida, Caribbean spiny lobsters (Panulirus argus) settle and spend their first few months in macroalgae or seagrass. After a few months, these ''algal-phase'' juveniles emerge from vegetation and, as ''postalgal-phase'' juveniles, seek refuge in crevices, often dwelling in groups. The importance of crevice shelters in determining the abundance of postalgal-phase juvenile spiny lobsters has been studied but we know little about the processes affecting lobster distribution and survival during their cryptic algal-dwelling phase. We found that postlarval supply varied independently of changes in the structure of macroalgal settlement habitat. For this reason, postlarval supply alone can not reliably …

Population-Dynamics Of Juvenile Caribbean Spiny Lobster, Panulirus-Argus, In Florida Bay, Florida, David Forcucci, Mark J. Butler Iv, John H. Hunt

Biological Sciences Faculty Publications

Despite a wealth of information on the growth and population dynamics of sub-adult and adult Caribbean spiny lobsters (Panulirus argus), there is far less information about younger juveniles under natural conditions. Here we describe growth and population dynamics of juvenile spiny lobsters (12-68 mm carapace length, CL) that we have studied for 14 months (October 1988-December 1989) using mark-recapture techniques in a hardbottom community in Florida Bay, Florida. We also monitored the supply of postlarvae into the region in 1988 and 1989 using Witham-type surface collectors in an effort to link peak periods of settlement of postlarvae with subsequent cohorts …