Ecology and Evolutionary Biology Commons^™

Size At Maturation, Spawning Variability And Fecundity In The Queen Conch, Aliger Gigas, Richard S. Appeldoorn

Gulf and Caribbean Research

The queen conch (Aliger gigas) resource is one of the most important in the Caribbean. While aspects of queen conch reproduction have been studied, e.g., size—at—maturity, spawning season, and density—based Allee effects, there is little information on other important aspects. From 210 lipped queen conch collected off southwest Puerto Rico, histological examination of gonads showed that 50% maturation occurred at 9 mm lip thickness. Experimental caged queen conch held on a natural spawning ground were monitored across the spawning season to evaluate fecundity and its variability across individuals and between nominal density treatments (2,000 vs 143 conch/ha). Near …

Spatiotemporal Variability Of Rockfish Recruitment On California's North Coast In Relation To Habitat Availability, Carolyn Belak

Cal Poly Humboldt theses and projects

Characterizing primary drivers of temporal and spatial variability in recruitment is imperative to understanding the role of pre- and post-settlement processes influencing marine population dynamics. On benthic reefs, the quality and quantity of suitable settlement habitat can alter post-settlement density-dependent mortality rates and increase chances of survival. The north coast of California has experienced highly unusual oceanographic conditions in recent years, leading to severe loss of highly productive kelp forests and potentially deleterious ecosystem consequences. In the present thesis, I aimed to determine the effects of canopy-forming bull kelp (Nereocystis) and alternative complex habitats on the recruitment of …

Multivariate Habitat-Based Predictive Modeling Of Three Demersal Rockfish Species In Central California, Georgia R. Martel

Cal Poly Humboldt theses and projects

Accurate, spatially explicit models of rockfish abundance are critical in implementing ecosystem-based management strategies and designating essential fish habitats and marine protected areas. Multibeam bathymetry methods and visual, non-extractive submersible transect surveys were combined to collect environmental variables and fish abundance data at three distinct sites within the study region. Zero-adjusted models were developed using habitat classification analyses of high-resolution (5 m) digital elevation models. Model accuracies were assessed by using a reserved subset of the original datasets. To demonstrate that a model’s predictive power was linked to its spatial origins, Mean Absolute Error and coefficient of determination values were …

Changes In Prey Mortality: The Efects Of Multiple Predators And Temperature On California Mussels, Wesley Hull

Cal Poly Humboldt theses and projects

Organisms serve as prey to a variety of predators within natural systems, detecting threats through physical and chemical means. While predator feeding behavior is also affected by the presence of other predators, it is unclear whether differing modes of detection have similar effects on predator feeding behavior. In rocky intertidal zones in northern California, the California mussel (Mytilus californianus) is a competitively dominant foundation species consumed by a variety of predators. I quantified the individual and combined effects of ochre star (Pisaster ochraceus) and rock crab (Romaleon antennarium) predation on mussels by implementing mussel …

Influence Of Diet And Abiotic Factors On The Survival And Reproduction Of Calanoid Copepod Pseudodiaptomus Annandalei, Abd Aziz Fatin Fatihah

Student Works (2020-2029)

The calanoid copepod, Pseudodiaptomus annandalei, due to its good nutritional value and significance as a natural diet of many tropical fish, is a superior live feed for marine fish larvae. Fish larvae needs a sustainable supply of good quality live feed for optimal growth and survival. Aims of this study were to investigate the effects of (1) marine mircroheterotrophs grown in palm oil mill effluent (POME) as copepod diet and (2) abiotic factors i.e. salinity (ppt), temperature (˚C), pH, photoperiod and light intensity on the survival and nauplii production of P. annandalei. Both biotic and abiotic experiments were conducted with …

The Effects Of Boring Sponge Infestation On Condition, Growth, And Sex Change In Crepidula Fornicata, Nicole L. Kleinas

College of Graduate Studies: Theses & Dissertations

The Atlantic slipper limpet, Crepidula fornicata, is a sequential hermaphrodite whose size at sex-change is plastic with respect to social and population cues. As an organism allocates energy between growth, reproduction and maintenance, an increased cost of one process may affect another. In this paper, I evaluate whether the presence of an epibiotic sponge (Cliona celata) affects the growth, condition and sex-change of C. fornicata individuals. Population surveys demonstrate a variable effect of Cliona presence on C. fornicata condition. The results of a twelve-week in situ experiment demonstrated a decrease in growth when C. celata was present. …

Estimates Of Red Drum Mortality Via Acoustic Telemetry, T. Reid Nelson, Sean P. Powers

University Faculty and Staff Publications

Subadult (age < 3) Red Drum Sciaenops ocellatus support a valuable recreational fishery, and mortality estimates for young Red Drum are needed for proper management. To obtain these estimates, age-1 and age-2 Red Drum were implanted with acoustic transmitters and external Floy tags in two coastal Alabama rivers (Fowl and Dog rivers). Fates of tagged fish were inferred from stationary receiver detections and active relocations over 1 year. These fates were used in a Bayesian multistate model to estimate instantaneous monthly and annual mortality and emigration rates for each river and overall from both rivers. Instantaneous monthly fishing mortality (F) ranged from 0.001 to 0.112 (annual F = 0.414) in Dog River, from 0.001 to 0.126 in Fowl River (annual F = 0.309), and was 0.001–0.054 (annual F = 0.337) overall. Instantaneous monthly natural mortality (M) ranged from 0.001 to 0.002 (annual M= 0.069) in Dog River, from 0.001 to 0.036 (annual M= 0.178) in Fowl River, and from 0.001 to 0.017 (annual M= 0.090) overall. The overall annual estimate of instantaneous total mortality (Z) was 0.435. The median escapement percentage was estimated at 36.3% (95% posterior credible interval = 19.5–56.0%) using M and Z from the overall model. Unfortunately, the error on this estimate was large and inconclusive as to whether the 30% escapement goal for juvenile Red Drum to the adult population from Dog and Fowl rivers is being met. Monthly residency estimates were typically greater than 0.90, and overall annual residency was estimated at 0.716. Fishing mortality estimates from the current study are higher than recent catch curve estimates that did not include young Red Drum. These results demonstrate that young Red Drum need to be accounted for when generating mortality estimates and provide needed data for the Red Drum recreational fishery.

Habitat Associations And Co-Occurrence Patterns Of Two Estuarine-Dependent Predatory Fishes, Mariah C. Livernois, Sean P. Powers, Mark A. Albins, John F. Mareska

University Faculty and Staff Publications

Estuarine-dependent fishes experience a wide range of environmental conditions, and most species exhibit distinct associations with particular habitats. However, similar species or multiple conspecifics often overlap spatiotemporally, which can result in ecological interactions that have consequences for behaviors that can shape the structure and function of ecosystems. We used a long-term gill-net data set (2001–2015) to investigate the habitat associations and cooccurrence patterns of two estuarine-dependent predatory fishes, Red Drum Sciaenops ocellatus and Spotted Seatrout Cynoscion nebulosus, in coastal Alabama, USA. Both species were associated with similar environmental conditions, primarily low dissolved oxygen and low salinity, especially when temperature was …

Impacts Of Ocean Acidification On Intertidal Macroalgae And Algivore Preference, Andrea Michelle Fieber

Cal Poly Humboldt theses and projects

Ocean acidification, a facet of global climate change, has the potential to induce changes in marine macroalgae that modify their existing interactions with algivorous invertebrates. In this study, I examined the effects of elevated carbon dioxide (pCO₂) on several species of intertidal macroalgae (Phaeophyta, Rhodophyta) and evaluated the present-day and predicted future preferences of algivores (Pugettia producta and Tegula funebralis) by assessing grazing rates on untreated algal tissue and on algae exposed to high-pCO₂ seawater. Both red and brown algae grew faster in elevated pCO₂ than in ambient seawater, …

Estimating The Heritability Of Plasticity Of Thermal Tolerance And Its Application In The Restoration Of Endangered Caribbean Coral, Matz O. Indergard

UNF Graduate Theses and Dissertations

Abstract

Over the last two centuries anthropogenic activity has elevated atmospheric CO₂, creating a greenhouse effect that is predicted to elevate global temperatures 1-4^o C within the century. Increases in surface temperature pose a threat to the world’s coral reefs and have been the cause of many mass bleaching events. To combat this new threat, corals must migrate, acclimate, or evolve to rising temperatures. Phenotypic plasticity, or the ability of an individual to express different phenotypes to survive in different environments, is crucial for sessile organisms since it can increase survivability in species incapable of moving to …

Exploring Eight-Armed Intelligence Through Film, Tierney M. Thys

Animal Sentience

Mather (2019) provides a rich overview of the elements underlying octopus cognition and behavioral flexibility. Recently, two remarkable natural history films, My Octopus Teacher and The Octopus in My House have explored intimate human-octopus relationships with a wild (Octopus vulgaris) and a captive octopus (Octopus cyanea) respectively. Both films show rare behaviors that offer observations to test new hypotheses as well as a novel perspective on our own human relationships and place within the natural world. An interview with filmmaker Craig Foster from My Octopus Teacher reveals the profound and transformative power of forming a trusting …

The Ecological Function Of Intertidal Seagrass For Sediment Entrapment On Middle Bank Shoal, Penang, Awang Nur Asilah

Student Works (2020-2029)

Application of seagrass in eco-engineering for sustainable coastal protection requires a deeper understanding of seagrass functions for sediment entrapment. Knowledge gaps on the influence of intertidal seagrass in trapping sediments raised two main questions in this study; (1) what is the relationship between intertidal seagrass meadow structure and trapped sediment? and (2) which part of the intertidal seagrass meadow structure best explains the variability of trapped sediment? To answer these questions, seagrass shoot density, Leaf Area Index (LAI), and total aboveground biomass were used as predictors for sediments deposition rate on Middle Bank Shoal. Three seagrass species were found; Enhalus …

The Effects Of Ship Wakes In The Venice Lagoon And Implications For The Sustainability Of Shipping In Coastal Waters, Gian Marco Scarpa, Luca Zaggia, Giorgia Manfe, Giuliano Lorenzetti, Kevin E. Parnell, Tarmo Soomere, John Rapaglia, Emanuela Molinaroli

Biology Faculty Publications

We analyse the impact of ship traffic in the vicinity of navigation channels in a wide shallow waterbody. The crucial hydrodynamic driver in this situation is the depression (Bernoulli) wake that may be transferred into a long-living solitary wave of depression over the shoals. The analysis considers navigation channels in the Venice Lagoon using a new large dataset of approximately 600 measured wake events associated to specific ships whose data are provided by the AIS system. Since the development of the modern industrial port and the opening of the Malamocco–Marghera channel in the late 1960s, growing pressure on the lagoon …

The Effects Of Seasonal Variations, El Niño-Southern Oscillation, And Climate Change On The Tuna-Dolphin Association, Caitlynn Birch, Michael D. Scott, Zhi-Yong Yin, Lisa T. Ballance

Theses

Tuna and dolphins swim together in the waters of the eastern tropical Pacific, and this association has long benefitted tuna fishermen and intrigued scientists. Although the tuna-dolphin association is often referred to as a “mystery,” much is known about the association. Yellowfin tuna are primarily caught with spotted dolphins and, to a lesser extent, spinner dolphins; historically the spotted dolphin has borne the brunt of the bycatch mortality. The tuna-dolphin association is thought to be a product of the distinct oceanography of the ETP: a shallow mixed layer, a thick oxygen minimum zone, and warm surface waters. As the mixed …

Scythes, Sickles And Other Blades: Defining The Diversity Of Pectoral Fin Morphotypes In Pachycormiformes, Jeff J. Liston, Anthony E. Maltese, Paul H. Lambers, Dominique Delsate, William E.H. Harcourt-Smith, Anneke H. Van Heteren

Publications and Research

The traditional terminology of ‘scythe’ or ‘sickle’ shaped is observed to be flawed as an effective descriptor for pectoral fin shape in pachycormids. The diversity of pachycormid pectoral fin shapes is assessed across the 14 recognised genera that preserve complete pectoral fins, and improved terms are defined to more effectively describe their form, supported by anatomical observation and aspect ratio analysis of individual fins, and corroborated by landmark analysis. Three clear and distinct pectoral fin structural morphotypes emerge (falceform, gladiform, falcataform), reflecting a diversity of pachycormid lifestyles throughout the Mesozoic, from agile pursuit predator to slow-cruising suspension feeder.

Habitat Associations And Reproduction Of Fishes On The Northwestern Gulf Of Mexico Shelf Edge, Elizabeth Marie Keller

LSU Doctoral Dissertations

Several of the northwestern Gulf of Mexico (GOM) shelf-edge banks provide critical hard bottom habitat for coral and fish communities, supporting a wide diversity of ecologically and economically important species. These sites may be fish aggregation and spawning sites and provide important habitat for fish growth and reproduction. Already designated as habitat areas of particular concern, many of these banks are also under consideration for inclusion in the expansion of the Flower Garden Banks National Marine Sanctuary. This project aimed to gain a more comprehensive understanding of the communities and fish species on shelf-edge banks by way of gonad histology, …

Hypoxia In Mangroves: Occurrence And Impact On Valuable Tropical Fish Habitat, Alexia Dubuc, Ronald Baker, Cyril Marchand, Nathan Waltham, Marcus Sheaves

School of Marine and Environmental Sciences Faculty and Staff Publications and Presentations

Intertidal mangrove forests are harsh environments that can naturally experience hypoxia in association with low tide. However, we know relatively little about dissolved oxygen (DO) fluctuations and DO-induced responses by fish, although DO is a fundamental water quality parameter. This study examines DO as a potential factor regulating the utilization of intertidal mangrove forests by fish and consequently their widely recognized feeding, refuge and nursery values. We deployed underwater video cameras, coupled with DO and depth loggers, in a mangrove forest to record changes in fish assemblages in response to tidal variations in DO and other associated environmental parameters. Our …

The Influence Of Location, Positioning, And Seasonality On Feeding Behavior Of The Sydney Oyster (Saccostrea Glomerata) In New South Wales, Australia, Nathaniel Hess

Independent Study Project (ISP) Collection

Oysters are hard shelled bivalves that aggregate over time to create structures in estuarine systems, known as oyster reefs. These reefs are important for the promotion of estuarine biodiversity by supporting many species of fish, invertebrates, and plants. They also act as a key contributor to water health by using active suspension feeding mechanisms and selective feeding to remove nutrients and water borne pollutants from estuarine systems. They have been touted as possible bio-remediators. They also effect rates of sedimentation in estuaries.

Oyster reefs have historically been threatened by anthropogenic influences such as overharvesting, destructive fishing practices, water pollution, CO2 …

Plasticity Of Foot Muscle And Cardiac Thermal Limits In The Limpet Lottia Limatula From Locations With Differing Temperatures, Terrance Wang, Richelle L. Tanner, Eric J. Armstrong, David R. Lindberg, Jonathon H. Stillman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Species distributions are shifting in response to increased habitat temperatures as a result of ongoing climate change. Understanding variation in physiological plasticity among species and populations is important for predicting these distribution shifts. Interspecific variation in intertidal ectotherms’ short-term thermal plasticity has been well established. However, intraspecific variation among populations from differing thermal habitats remains a question pertinent to understanding the effects of climate change on species’ ranges. In this study, we explored upper thermal tolerance limits and plasticity of those limits using a foot muscle metric and 2 cardiac metrics (Arrhenius breakpoint temperature, ABT, and flatline temperature, FLT) in …

Fucus Distichus: Investigating Humidity And Temperature Between Tides, Jason Thomas, Andrew Chang, Julia Blum, Chela Zabin

STAR Program Research Presentations

Environmental elements such as changing rapidly changing temperature, prolonged periods of low to no water exposure, desiccation, predation and increased wave action can influence the diversity of microhabitats that inhabit the littoral zones. When making observations of various shorelines, specifically the physical conditions of the surrounding marine vegetation (i.e. Fucus distichus), an inquiry is made as to the role of Fucus in the amelioration of stressors on the marine habitat during low tide (MLLW), however, due to time considerations, temperature and humidity are the focus of this study. Using temperature and humidity probes, monitoring data shows that Fucus provides …

The ‘Law Of Environmental Dependence’ - Biology And Ethics In The Work Of Ernest Everett Just: + Found – Some 251 Mostly Typed Pages, Theodore Walker

Perkins Faculty Research and Special Events

Abstract-

“The Origin of Man’s Ethical Behavior” (circa October 1941) by Ernest Everett Just and Hedwig A. Schnetzler Just - is an unpublished book manuscript about the biological origins and evolution of ethical behavior, and about “the law of environmental dependence.” Missing since Just’s death in October 1941, it was found and identified in May 2018 among the collected papers of Ernest Everett Just preserved at the Howard University Moorland-Spingarn Research Center in Washington, DC. In addition to the 1996 US postage with the caption “Ernest E. Just, Biologist,” we now have reason to add two new postage stamps with …

Coral Reef Change Detection In Remote Pacific Islands Using Support Vector Machine Classifiers, Justin J. Gapper, Hesham El-Askary, Erik Linstead, Thomas Piechota

Mathematics, Physics, and Computer Science Faculty Articles and Research

Despite the abundance of research on coral reef change detection, few studies have been conducted to assess the spatial generalization principles of a live coral cover classifier trained using remote sensing data from multiple locations. The aim of this study is to develop a machine learning classifier for coral dominated benthic cover-type class (CDBCTC) based on ground truth observations and Landsat images, evaluate the performance of this classifier when tested against new data, then deploy the classifier to perform CDBCTC change analysis of multiple locations. The proposed framework includes image calibration, support vector machine (SVM) training and tuning, statistical assessment …

Sex-Specific Personalities In The Purple Marsh Crab, Jillian Sterman, Jessica Barton, Panagiota Delmedico, Samantha Sweeney

DePaul Discoveries

Animals are considered to possess personalities when individuals differ in behavior, and these differences are consistent between situations. Several studies have identified personalities in diverse groups but less is known about personality variation between the sexes. In this study, we examined variation in two key personality traits (boldness, activity) in female and male purple marsh crabs (Sesarma reticulatum) using a semi-field approach. Specifically, we measured boldness and activity on two consecutive days using the same behavioral assays during each time point. Consistency (personality) was determined using Kendall’s coefficient of concordance based on Spearman correlation coefficients for each behavior. …

Effects Of Reduced Ph On Health Biomarkers Of The Seagrass Cymodocea Nodosa, Regan A. Mcenaney

DePaul Discoveries

Ocean acidification is a growing problem that may affect many marine organisms in the future. Within 100 years the pH of the ocean is predicted to decrease to 7.8, from the current ocean pH of around 8.1. Using phenolic acid levels as a stress indicator as well as respiration and chlorophyll content as a measure of health, the effect of lowering pH was tested on the seagrass, Cymodocea nodosa, in a controlled environment. Plant samples, water, and soil were taken from the Bay of Cádiz, Spain, and placed in aquaria in a temperature-controlled room. One control group was left …

Leonardo And The Whale, Kay Etheridge

Biology Faculty Publications

Around 1480, when he was 28 years old, Leonardo da Vinci recorded what may have been a seminal event in his life. In writing of his travels to view nature he recounted an experience in a cave in the Tuscan countryside:

Having wandered for some distance among overhanging rocks, I can to the entrance of a great cavern... [and after some hesitation I entered] drawn by a desire to see whether there might be any marvelous thing within..."

[excerpt]

High Heat Tolerance Is Negatively Correlated With Upper Thermal Tolerance Plasticity In North Eastern Pacific Nudibranch Mollusks, Eric J. Armstrong, Richelle L. Tanner, Jonathon H. Stillman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Rapid ocean warming may alter habitat suitability and population fitness for marine ectotherms. Susceptibility to thermal perturbations will depend in part on plasticity of a species’ upper thermal limits of performance (CT_max). However, we currently lack data regarding CT_max plasticity for several major marine taxa, including nudibranch mollusks, thus limiting predictive responses to habitat warming for these species. In order to determine relative sensitivity to future warming, we investigated heat tolerance limits (CT_max), heat tolerance plasticity (acclimation response ratio), thermal safety margins, temperature sensitivity of metabolism, and metabolic cost of heat shock in nine species …

Density And Species Richness Of Macrofaunal Benthic Bivalves In North Inlet Estuary, South Carolina, Richard Hawley, Juliana Harding

Honors Theses

Marine benthic bivalves are consumed by higher trophic levels. Bivalve species richness and density depend on temperature, salinity, and location. Biweekly core samples were collected from Bly Creek from 12/2017 to 12/2018. Benthic macrofaunal bivalves were counted and identified to describe density and species richness. Bivalves were also photographed for species identification. Bivalves composed 0% to 17% of the total macrofauna. The maximum bivalve density (8,149 bivalves/m²) was recorded on December 23, 2018. The fewest bivalves were observed from December 2017 through March 2018. Eight bivalve species were recorded during 2018; at least one species was present year-round. …

Demersal Fish Use Of Printed Oyster Shells As Nesting Habitat In North Inlet Estuary, Sc, Annie Boyd, Juliana Harding

Honors Theses

Temperate estuarine blenny species establish subtidal territories and nesting sites. Four blenny species co-occur in North Inlet, SC including the striped blenny, Chasmodes bosquianus, crested blenny, Hypleurochilus geminatus, feather blenny, Hypsoblennius hentzi, and freckled blenny, Hypsoblennius ionthas. All four fishes use empty oyster (Crassostrea virginica) shells as nesting sites. Current 3D printer technology was used to create standard nest substrates to describe relationships between blenny habitat use and nest site dimensions. Replicate printed shells of 2 gape widths (5, 7 mm) for each of 2 shell cavity volumes (22 mL, 15mL, Oyster A and …

Examining The Effect Of Interstitial Space On Eastern Oysters (Crassostrea Virginica): Applications Of Photogrammetry And Three-Dimensional Modeling, Bailie Lavan

Masters Theses, 2010-2019

Global oyster populations have decreased by as much as 99% in the past century. Oysters are known ecosystem engineers, providing benthic habitat for macrofauna, linking benthic and pelagic food webs, improving water quality, and mitigating shoreline erosion. Restoration efforts are critical in re-establishing native oyster populations. In the Chesapeake Bay, where oyster loss is primarily due to severe over harvest, artificial substrates with geometric shapes are widely used in restoration efforts. However, natural oyster reefs form emergent shapes with a high degree of aggregation and many interstitial spaces (three-dimensional volumetric spaces between oysters within a reef). The lack of interstitial …

Correlation Between Sei Whale Distribution And Chlorophyll-A Concentration In The Western North Atlantic, Dawn Parry

Senior Honors Projects

The sei whale (Balaenoptera borealis) is an endangered baleen whale species whose distribution and migratory movements are poorly understood. Sei whale populations were decimated by commercial whaling in the 19th and 20th centuries. Much of what is currently known about their distributions comes from historical whaling records. Visual sightings, which may be sporadic and limited by weather and access to remote locations, are the primary source of data for recent research. It is thought that sei whale distributions may be influenced by the distribution of their food, which consists of zooplankton (small crustaceans, like shrimp), small fish, and …