Digital Commons Network^™

Rapid Recovery Of A Coral Reef At Darwin Island, Galapagos Island, Peter W. Glynn, Bernhard Riegl, Adrienne M. S. Correa, Iliana B. Baums

Bernhard Riegl

Surveys at Darwin Island in 2006 and 2007 have demonstrated that this northernmost Galapagos Islands coral reef has recovered significantly since the 1982-3 El Nino event. When first surveyed in 1975, this structural reef exhibited actively accreting frameworks of pocilloporid and poritid corals. The coral suffered severe mortality in 1983, resulting in the near total loss of pocilloporids and extensive partial mortality of poritid corals. Large sections of the reef had not recovered by 1992 and dead frameworks were subject to bio-erosion, although small numbers of sexual recruits of pocilloporid corals and numerous recruits plus regenerating patches of Porites lobata …

Environmental Impacts Of Dredging And Other Sediment Disturbances On Corals: A Review, Paul. L. A. Erftemeijer, Bernhard Riegl, Bert W. Hoeksema, Peter A. Todd

Bernhard Riegl

A review of published literature on the sensitivity of corals to turbidity and sedimentation is presented, with an emphasis on the effects of dredging. The risks and severity of impact from dredging (and other sediment disturbances) on corals are primarily related to the intensity, duration and frequency of exposure to increased turbidity and sedimentation. The sensitivity of a coral reef to dredging impacts and its ability to recover depend on the antecedent ecological conditions of the reef, its resilience and the ambient conditions normally experienced. Effects of sediment stress have so far been investigated in 89 coral species (∼10% 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, …

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 …

Bacterial Community Profiling Of The Eastern Oyster (Crassostrea Virginica): Comparison Of Culture-Dependent And Culture-Independent Outcomes, Kenneth J. La Valley, Steve Jones, Marta Gomez-Chiarri, Joseph Dealteris, Michael A. Rice

Michael A Rice

Tissue-associated bacterial community profiles generated using a nested polymerase chain reaction–denaturing gradient gel electrophoresis (DGGE) approach and culture-dependent and culture-independent isolation techniques were compared. Oyster samples were collected from 2 harvest areas along the coast of Maine, in the United States. Profiles from both isolation strategies were evaluated using Sorensen’s index of similarity and cluster analysis of gel banding patterns. Cultureindependent profiles were further evaluated using the Shannon diversity index. In general, the culture-dependent strategy resulted in a greater number of bands within a profile. BacterialDGGEprofiles were found to be highly similar within an isolation strategy, with a higher degree …

Divergence In Thyroid Hormone Concentrations Between Juveniles Of Marine And Stream Ecotypes Of The Threespine Stickleback (Gasterosteus Aculeatus), Jun Kitano, Sean C. Lema

Sean Lema

Background: Hormones regulate the expression of multiple phenotypic traits. Therefore,

divergence in hormone concentrations may lead to evolutionary changes in the coordinated

physiological and behavioural traits that comprise an organism’s integrated phenotype. Adults

of marine ecotypes of threespine stickleback (Gasterosteus aculeatus) have higher concentrations

of the thyroid hormone thyroxine (T4) than adults of stream-resident ecotypes (Kitano

et al., 2010). Thyroid hormones are well-established mediators of osmoregulation and migratory

behaviours in fish, and the difference in T4 concentrations indicates that changes in thyroid

hormone signalling may underlie the evolutionary and ecological divergence of migratory and

non-migratory ecotypes.

Questions: Is the variation …

Effects Of Flow Restoration On Mussel Growth In A Wild And Scenic North American River, Brandon J. Sansom, Daniel J. Hornbach, Mark C. Hove, Jason S. Kilgore

Daniel J. Hornbach

No abstract provided.

Health Effects Of Trihalomethanes As Chlorinated Disinfection By Products: A Review Article, Mohammad Reza Mohammad Shafiee, Lobat Taghavi

Mohammad Reza Mohammad Shafiee

Trihalomethanes (THMs) were among the first disinfection byproducts to be discovered in chlorinated water. The substances form during a reaction between chlorine and organic matter in the water. Trihalomethanes are suspected to have negative effects on birth such as, low birth weight, intrauterine growth retardation in term births, as well as gestational age and preterm delivery. There are also some evidences showing these by-products to be mutagenic and carcinogenic, the greatest amount of evidence being related to the bladder cancer. However, there exist inconsistencies regarding such effects of THMs as different studies have provided different results in this regard. The …

Life On The Edge: Morphological And Behavioral Adaptations For Survival On Wave-Swept Shores, Luke P. Miller

Luke P. Miller

Wave-swept rocky shores serve as a home to a great diversity of organisms and are some of the most biologically productive habitats on earth. This burgeoning community exists in spite of the fact that the zone between the high and low tide marks can be one of the most physically harsh environments on earth. Large forces imposed by breaking waves and wide swings in temperature require the organisms living on rocky shores to adapt to a constantly changing environment or risk extirpation by physical forces. I have explored a number of hypothesized adaptations for survival on rocky shores and discuss …

Perspectives In Ornithology: Application Of Tracking And Data-Logging Technology In Research And Conservation Of Seabirds, A E. Burger, Scott A. Shaffer

Scott A. Shaffer

No abstract provided.

Interpolation Of Tracking Data In A Fluid Environment, Y Tremblay, Scott A. Shaffer, S L. Fowler, C E. Kuhn, B I. Mcdonald, M J. Weise, C -A Bost, H Weimerskirch, D E. Crocker, M E. Goebel, D P. Costa

Scott A. Shaffer

Interpolation of geolocation or Argos tracking data is a necessity for habitat use analyses of marine vertebrates. In a fluid marine environment, characterized by curvilinear structures, linearly interpolated track data are not realistic. Based on these two facts, we interpolated tracking data from albatrosses, penguins, boobies, sea lions, fur seals and elephant seals using six mathematical algorithms. Given their popularity in mathematical computing, we chose Bézier, hermite and cubic splines, in addition to a commonly used linear algorithm to interpolate data. Performance of interpolation methods was compared with different temporal resolutions representative of the less-precise geolocation and the more-precise Argos …

Evaluation Of Eelgrass Mitigation And Fishery Enhancement Structures In San Diego Bay, California, Daniel Pondella Ii

Daniel Pondella

To offset habitat loss and increase fishery production, an eelgrass mitigation habitat was completed in San Diego Bay, California in 1997. This mitigation effort consisted of the transplantation of eelgrass, Zostera marina L., in the western portion of the bay. In addition to the establishment of a new eelgrass bed, four enhancement reefs made of either quarry rock or concrete rubble were created to further enhance fishery stocks and the area's ecosystem. Two design criteria and a direct comparison between quarry rock and concrete reefs were examined in this 5-yr pilot program. The newly created eelgrass habitat quickly performed at …