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Octopus Tetricus (Mollusca: Cephalopoda) As An Ecosystem Engineer, David Scheel, Peter Godfrey-Smith, Matthew Lawrence

Publications and Research

The Sydney octopus (Octopus tetricus) occurs in unusual numbers on a shell bed of its prey remains that have accumulated as an extended midden where additional octopuses excavate dens. Here, O tetricus are ecosystem engineers, organisms that modulate availability of resources to other species and to their own species by causing physical state changes in materials. A community of invertebrate grazers and scavengers has developed on the shell bed. Fishes are attracted to the shell bed in numbers significantly greater than in nearby habitats. Large predators, including wobbegong sharks, were attracted to and fed on concentrations of fish, inhibiting the …

Persistence And Change In Community Composition Of Reef Corals Through Present, Past, And Future Climates, Robert Van Woesik, Peter J. Edmunds, Mehdi Adjeroud, Marissa L. Baskett, Iliana B. Baums, Ann F. Budd, Robert C.C. Carpenter, Nicholas S. Fabina, Tungyung Fan, Eric C. Franklin

Ocean Engineering and Marine Sciences Faculty Publications

The reduction in coral cover on many contemporary tropical reefs suggests a different set of coral community assemblages will dominate future reefs. To evaluate the capacity of reef corals to persist over various time scales, we examined coral community dynamics in contemporary, fossil, and simulated future coral reef ecosystems. Based on studies between 1987 and 2012 at two locations in the Caribbean, and between 1981 and 2013 at five locations in the Indo-Pacific, we show that many coral genera declined in abundance, some showed no change in abundance, and a few coral genera increased in abundance. Whether the abundance of …

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata (Olivellidae, Gastropoda), Two Key Species In Panamic Sandy Beach Ecosystems?, Allison I. Troost, Samantha D. Rupert, Ariel Z. Cyrus, Frank V. Paladino, Benjamin F. Dattilo, Winfried S. Peters

Benjamin F. Dattilo

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension-feeding, swash-surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and museum collections, …

Rapid: Natural Laboratories In The Chilean Fjords: Studying Reproduction And Development In Emergent Deep-Sea Corals, Rhian G. Waller

University of Maine Office of Research Administration: Grant Reports

Intellectual Merit

The northern Patagonian fjords lie on the interface between the high Andes Mountains in the east and the South Pacific Ocean, formed thousands of years ago through erosive glacial activity and tectonic sinking. Around 12,000 years ago the icefields in the Chiloé Interior Sea began to open, leaving behind over 15,000km2 of fjords, channels and gulfs. The waters within the fjords are influenced by strong tides, large volumes of freshwater runoff, and upwelling of deep-ocean waters as well as steep climatic gradients from north to south. This dynamic environment has resulted in extremely high biodiversity and endemism, yet …

Abundance And Diversity Of Ammonia-Oxidizing Archaea And Bacteria In Sediments Of Trophic End Members Of The Laurentian Great Lakes, Erie And Superior, Annette Bollmann, George S. Bullerjahn, Robert Michael Mckay

Great Lakes Institute for Environmental Research Publications

Ammonia oxidation is the first step of nitrification carried out by ammonia-oxidizing Archaea (AOA) and Bacteria (AOB). Lake Superior and Erie are part of the Great Lakes system differing in trophic status with Lake Superior being oligotrophic and Lake Erie meso- to eutrophic. Sediment samples were collected from both lakes and used to characterize abundance and diversity of AOA and AOB based on the ammonia monooxygenase (amoA) gene. Diversity was accessed by a pyro-sequencing approach and the obtained sequences were used to determine the phylogeny and alpha and beta diversity of the AOA and AOB populations. In Lake Erie copy …

Historical Reconstruction Of Population Density Of The Echinoid Diadema Antillarum On Florida Keys Shallow Bank-Barrier Reefs, Donald L. Kissling, William F. Precht, Steven Miller, Mark Chiappone

Marine & Environmental Sciences Faculty Articles

The 1983–1984 caribbean-wide mass mortality of the once ubiquitous long-spined sea urchin Diadema antillarum Philippi, 1845, is one of several factors considered responsible for coral reef change throughout the region. Unfortunately, there is a paucity of pre-mortality event density data for D. antillarum in the Florida Keys, making it difficult to determine pre-1983 population density levels. results from surveys conducted during 1970–1973 in the lower Florida Keys, in shallow (<12 m) fore reef habitats, yielded relatively abundant and widespread D. antillarum densities in qualitative transects at five reefs prior to the 1983–1984 die-off. In quantitative surveys at one reef, Middle sambo reef in 1972, up to 7.9 individuals m …

A Case Study Of Rhincodon Typus Scarring In Ningaloo Reef: An Assessment Of The Current Scarring Classification System, Laura Korman

Independent Study Project (ISP) Collection

Rhincodon typus are the largest fish in the sea, but little is understood about this elusive species. They are known to annually aggregate in Ningaloo Reef, Western Australia—the location of this study. In order to better understand this species, scarring was observed on a subset of the population that aggregates in Ningaloo Reef. In addition, the scarring classification system was examined to determine if it is the most effective classification system. R. typus were observed, and photographed from April 9th-April 25th, 2014. These photos were then used for identification and scarring classification purposes. The analysis of the scars on R. …

Environmental And Individual Factors Shaping The Habitat Use And Trophic Interactions Of Juvenile Bull Sharks (Carcharhinus Leucas) In A Subtropical Estuary, Philip Matich

FIU Electronic Theses and Dissertations

Top predators serve important roles within their respective ecosystem through top-down and bottom-up effects, yet understanding how these roles vary among individuals within predator populations is still in its early stages. Such individuality can have important implications for the functional roles predators play within their respective ecosystems. Therefore, elucidating the factors that drive persistent individual differences within populations is crucial for understanding how individuals, and in turn populations, will respond to environmental changes and anthropogenic stressors, and the implications of these responses for particular ecological functions. In this dissertation I investigated the movements, residency patterns, and trophic interactions of a …

Ontogenetic Variation In Epibiont Community Structure In The Deep-Sea Yeti Crab, Kiwa Hirsuta: Convergence Among Crustaceans, Shana Goffredi, Ann Gregory, William Jones, Norma Morella, Reid Sakamoto

Shana Goffredi

Recent investigations have demonstrated that unusually 'hairy' yeti crabs within the family Kiwaidae associate with two predominant filamentous bacterial families, the Epsilon and Gammaproteobacteria. These analyses, however, were based on samples collected from a single body region, the setae of pereopods. To more thoroughly investigate the microbiome associated with Kiwa puravida, a yeti crab species from Costa Rica, we utilized barcoded 16S rRNA amplicon pyrosequencing, as well as microscopy and terminal restriction fragment length polymorphism analysis. Results indicate that, indeed, the bacterial community on the pereopods is far less diverse than on the rest of the body (Shannon indices ranged …

Utilization Of The Invasive Alga Gracilaria Vermiculophylla (Ohmi) Papenfuss By The Native Mud Snail Ilyanassa Obsoleta (Say), Michele Guidone, Christine Newton, Carol S. Thornber

Biology Faculty Publications

The recent invasions of the red alga, Gracilaria vermiculophylla, to the Atlantic and Eastern Pacific Oceans have the potential to significantly alter intertidal and subtidal soft sediment communities. In particular, G. vermiculophylla increases habitat complexity and provides a novel hard substrate in an otherwise two dimensional habitat. Following our observations that the native omnivorous mud snail Ilyanassa obsoleta utilizes G. vermiculophylla for egg capsule deposition, our field surveys demonstrated that the in situ abundance of egg capsules on G. vermiculophylla matched abundances on a native alga Ceramium virgatumandwere at least 11–50 times greater than on all other co-occurring macrophytes. Additionally, …

Growth Of The Marine Fish-Killing Phytoflagellate, Heterosigma Akashiwo Under Emerging Coastal Regimes: Temperature, Eutrophication And Ocean Acidification, Cayla M. Bronicheski

Electronic Thesis and Dissertation Repository

Coastal oceans are fundamental to human economies, nutrition and recreation. Anthropogenic stressors have led to the acceleration of the nitrogen cycle, the accumulation of inorganic carbon in the earth’s atmosphere, the loss of UV-scavenging upper atmospheric ozone and the overall accumulation of deep elements from the earth’s crust to surface exposure. These changes have caused ocean acidification and eutrophication events in coastal waters and the impacts of these events on primary production and ocean biodiversity are not yet fully understood.

This study examined the effects of predicted future ocean conditions (salinity, temperature, reduced seawater pH and modified nitrogen supplies), on …

Post Disturbance Coral Populations: Patterns In Live Cover And Colony Size Classes From Transect Studies In Two Oceans, Claire A. Dolphin

HCNSO Student Theses and Dissertations

This study analyzes data acquired in French Polynesia in the Pacific and The Bahamas (Atlantic), both oceans affected by recent, well documented and sequential disturbances. For the purposes of this study, a disturbance is defined as a perturbation of environmental, physical or biological conditions that causes a distinct change in the ecosystem. After several decades of coral bleaching events, biological change, and anthropogenic impacts, rapid assessments of the coral community were accomplished by collecting photo-transects across the reefs to extract size structure of the corals, percent live tissue cover and perform a faunal evaluation. Cluster analyses and spatial autocorrelation tests …

Evolution Of The Freshwater Sardinella, Sardinella Tawilis (Clupeiformes: Clupeidae), In Taal Lake, Philippines And Identification Of Iits Marine Sister-Species, Sardinella Hualiensis, Demian Willette, Kent E. Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

We identify the sister species of the world's only freshwater sardinella, Sardinella tawilis (Herre, 1927) of Taal Lake, Philippines as the morphologically-similar marine Taiwanese sardinella Sardinella hualiensis (Chu and Tsai, 1958). Evidence of incomplete lineage sorting and a species tree derived from three mitochondrial genes and one nuclear gene indicate that S. tawilis diverged from S. hualiensis in the late Pleistocene. Neutrality tests, mismatch distribution analysis, sequence diversity indices, and species tree analysis indicate populations of both species have long been stable and that the divergence between these two lineages occurred prior to the putative 18th century formation of Taal …

Integrating Societal Perspectives And Values For Improved Stewardship Of A Coastal Ecosystem Engineer, Steven B. Scyphers, J. Steven Picou, Robert D. Brumbaugh, Sean P. Powers

University Faculty and Staff Publications

Oyster reefs provide coastal societies with a vast array of ecosystem services, but are also destructively harvested as an economically and culturally important fishery resource, exemplifying a complex social-ecological system (SES). Historically, societal demand for oysters has led to destructive and unsustainable levels of harvest, which coupled with multiple other stressors has placed oyster reefs among the most globally imperiled coastal habitats. However, more recent studies have demonstrated that large-scale restoration is possible and that healthy oyster populations can be sustained with effective governance and stewardship. However, both of these require significant societal support or financial investment. In our study, …