Chris Langdon

Chris Langdon
Oregon State University | OSU · Department of Fisheries and Wildlife

PhD

About

187
Publications
23,264
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6,393
Citations
Citations since 2017
36 Research Items
2563 Citations
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Introduction
Chris Langdon currently works at the Department of Fisheries and Wildlife, and Coastal Oregon Marine Experiment Station, Oregon State University. Chris carries out research in a wide range of subjects, including nutrition of marine suspension-feeders, such as oysters and fish larvae, genetics and breeding of Pacific oysters, polyculture, and macroalgal culture.

Publications

Publications (187)
Article
Full-text available
This study assessed the productivity of the red alga Palmaria mollis (Pacific dulse) plantlets immobilized on a vertical array of mesh panels in aerated tank culture. Biomass productivity rates based on panel surface area, as well as areal productivity based on liquid surface area, were assessed at different panel spacing intervals in a greenhouse...
Article
Owing to its high nutritional value and widespread availability, the legume alfalfa Medicago sativa (Linnaeus, 1753) is a possible feed for aquatic animals. In this study, a dried alfalfa chloroplast (DAC) product supplied by Virentia Inc., Quebec, Canada, was evaluated as a partial or total replacement for live microalgae (LM) in diets for juvenil...
Article
Full-text available
The adaptive capacity of marine calcifiers to ocean acidification (OA) is a topic of great interest to evolutionary biologists and ecologists. Previous studies have provided evidence to suggest that larval resilience to high pCO2 seawater for these species is a trait with a genetic basis and variability in natural populations. To date, however, it...
Article
Full-text available
Balancing selection is one of the mechanisms which has been proposed to explain the maintenance of genetic diversity in species across generations. For species with large populations and complex life histories, however, heterogeneous selection pressures may create a scenario in which the net effects of selection are balanced across developmental st...
Article
Yearly mass mortalities of Pacific oysters in a major oyster-growing estuary on the West Coast of the United States (Tomales Bay, California) present a constraint to shellfish aquaculture. These mortalities have been associated with the presence of Ostreid herpesvirus 1 (OsHV-1; Tomales Bay strain) and increased seawater temperature in the estuary....
Article
The present study determined the effect of larval stocking density on larval yield (number of live larvae at the end of the experiment), competent larvae (number of live larvae at the end of the experiment retained on a sieve with mesh size of 236 μm (1st experiment) and 239 μm (2nd experiment)), and larval shell length of Crassostrea gigas in a re...
Article
We describe the introduction, taxonomic identification and genetic parameters for farm traits of the Midori strain of the Pacific oyster Crassostrea gigas - a possible alternative to the widely farmed Miyagi strain on the US West Coast. Broodstock (G0) oysters collected from the mouth of the Midori river and near Iwajima Island, Ariake Bay, Japan w...
Article
Full-text available
Pacific oysters, Crassostrea gigas, are one of the most productive aquaculture species in the world. However, they are threatened by the spread of Ostreid herpesvirus-1 (OsHV-1) and its microvariants (collectively “µvars”), which cause mass mortalities in all life stages of Pacific oysters globally. Breeding programs have been successful in reducin...
Article
Full-text available
Background: Variants of the Ostreid herpesvirus 1 (OsHV-1) cause high losses of Pacific oysters globally, including in Tomales Bay, California, USA. A suite of new variants, the OsHV-1 microvariants (μvars), cause very high mortalities of Pacific oysters in major oyster-growing regions outside of the United States. There are currently no known Pac...
Article
Several Pacific oysters breeding programs selecting for improved aquaculture traits have been described in the literature; however, there are differences in the approaches and traits under selection. Here we discuss the approach and results of the Molluscan Broodstock Program (MBP) to improve traits of interest for US West Coast oyster farmers. In...
Article
Ocean acidification (OA) has had significant negative effects on oyster populations on the west coast of North America over the past decade. Many studies have focused on the physiological challenges experienced by young oyster larvae in high pCO2/low pH seawater with reduced aragonite saturation state (Ωarag), which is characteristic of OA. Relativ...
Article
Full-text available
The use of chemical dispersants during oil spill responses has long been controversial. During the Deepwater Horizon (DWH) oil spill, 1.8 million gallons of dispersant, mainly Corexit 9500, were applied in offshore waters to mitigate the human health and coastal environmental impact of surface oil contamination. To evaluate the potential impact of...
Article
One of the key limitations in the use of artificial microdiets for the culture of marine fish larvae and post-larvae is their poor acceptability. The chemosensory systems of adult and juvenile fish are known to serve important roles in the detection and selection of food items; however, the relative importance and functionality of chemosensory dete...
Article
Carbonate chemistry variables such as PCO2, pH, and mineral saturation state (Ω) are commonly thought of as covarying in open‐ocean settings but have decoupled over geologic time‐scales and among modern dynamic coastal margins and estuaries. Predicting responses of vulnerable coastal organisms to past, present, and future ocean acidification (OA) s...
Article
Free access until November 28, 2018: https://authors.elsevier.com/c/1XsSoACeXzgRM
Article
The native Olympia oyster (Ostrea lurida) has been the subject of few detailed feeding studies compared with many other species of bivalve mollusk. More information on this species’ feeding activity and behavior are needed to better understand its historical ecological role in Pacific Northwest (PNW) estuaries, compared with that of the widely farm...
Article
Full-text available
US west coast populations of the native Olympia oyster Ostrea lurida declined precipitously in the late nineteenth and early twentieth centuries and were often replaced by the non-native Pacific oyster (Crassostrea gigas) by the aquaculture industry. Recovery of native oyster ecosystem services derived from their suspension feeding activities (term...
Article
Full-text available
(1) Background: The red seaweed Palmaria mollis (PM), which has a bacon-like taste, is increasingly being included in Western diets. In this study, we evaluate anti-obesity effects of PM using diet-induced obese (DIO) zebrafish and mice models. (2) Methods: We fed PM-containing feed to DIO-zebrafish and mice, and evaluated the anti-obesity effects...
Article
Full-text available
In the original article there is an error on page 522 in the third paragraph of the Methods section. There is an erroneous 0 in the TWW coefficient. The corrected text is as follows.
Article
During the Deepwater Horizon oil spill rapid natural weathering of Macondo crude oil occurred during the transport of oil to coastal areas. In response to the DWH incident, dispersant was applied to Macondo crude oil to reduce the movement of oil to coastal regions. This study aimed to assess the narcotic and phototoxicity of water-accommodated fra...
Article
Genetic by environment (GxE) interactions were estimated for harvest traits of Pacific oysters Crassostrea gigas based on data collected over a period of 20 y from farm trials conducted by the Molluscan Broodstock Program, a family-based selective breeding program aimed at improving yields of Pacific oysters on the West Coast, USA. Genetic by envir...
Article
Full-text available
Background: Despite recent work to characterize gene expression changes associated with larval development in oysters, the mechanism by which the larval shell is first formed is still largely unknown. In Crassostrea gigas, this shell forms within the first 24 h post fertilization, and it has been demonstrated that changes in water chemistry can ca...
Article
Full-text available
Background: The red seaweed Palmaria mollis (PM) has recently become popular as foodstuffs due to their relatively high proteins, in addition to their potential as a source of biofunctional molecules and antioxidant ingredients. We previously performed small-scale screening with diet-induced obese (DIO) zebrafish, and found that PM is one of strong...
Article
Full-text available
The World Register of Marine Species (WoRMS) currently registers all Pacific cupped oysters that were formerly members of the genus Crassostrea in a new genus, Magallana. Magallana gigas is designated as an ‘‘accepted name,’’ whereas a search for Crassostrea gigas results in the message ‘‘no matching results found.’’ This has caused dismay among ma...
Article
Full-text available
The native Olympia oyster, Ostrea lurida, was once abundant in many US Pacific Northwest (PNW) estuaries, but was decimated by human activity in the late nineteenth early to twentieth centuries. Having been the subject of only few modern, detailed studies, a dearth of basic physiological information surrounded O. lurida and how it compared to the n...
Article
Full-text available
Ocean acidification (OA) - a process describing the ocean’s increase in dissolved carbon dioxide (PCO2) and a reduction in pH and aragonite saturation state (Ωar) due to higher concentrations of atmospheric CO2 – is considered a threat to bivalve mollusks and other marine calcifiers. While many studies have focused on the effects of OA on shell for...
Article
To optimize diet particle size for ingestion by zebrafish larvae, Danio rerio, a series of diet selection experiments were carried out using two different length classes: 5-day-old, first feeding larvae with a mean standard length (MLs) of 3.8 mm and 15-day-old larvae with MLs of 5.2 mm. For this purpose, crosslinked protein-walled capsules with fi...
Article
Polycyclic aromatic hydrocarbons (PAHs) have been reported to absorb ultraviolet (UV) light, resulting in enhanced toxicity. Early developmental stages of bivalves may be particularly susceptible to photo-enhanced toxicity during oil spills. In the current study, toxicity tests were conducted with sperm and three larval ages of the eastern oyster (...
Article
Full-text available
Increasing anthropogenic carbon dioxide is altering marine carbonate chemistry through a process called ocean acidification. Many calcium carbonate forming organisms are sensitive to changes in marine carbonate chemistry, especially mollusk bivalve larvae at the initial shell building stage. Rapid calcification, limited energy reserves, and more ex...
Article
The Pacific oyster, Crassostrea gigas, is one of the most important global aquaculture species due to its potential high growth rates and tolerance of a wide range of environmental conditions; however, most farmers use seed from wild, non-domesticated stocks for production. In this study we estimated genetic parameters for performance traits of oys...
Presentation
Full-text available
Worldwide, many native oyster populations have been severely depleted. In the Pacific Northwest (PNW), large-scale restoration efforts for the native Olympia oyster (Ostrea lurida) are currently underway to augment stocks in order to regain their ecosystem services, particularly those related to filter-feeding activity. An important limitation in e...
Article
Acute toxicity tests (48 to 96 hours duration) were conducted with larvae of two echinoderm species (Strongylocentrotus purpuratus and Dendraster excentricus) and four bivalve mollusk species (Crassostrea virginica, Crassostrea gigas, Mytilus galloprovincialis, and Mercenaria mercenaria). Developing larvae were exposed to water-accommodated fractio...
Article
In this study we examined the effects of chronic exposure of eastern oyster (Crassostrea virginica) larvae to the water-accommodated fractions of fresh and weathered oils collected from the Deepwater Horizon (DWH) incident, with and without additions of the dispersant Corexit 9500A, as well as to solutions of Corexit alone. We found that both shell...
Poster
Full-text available
The native Olympia oyster Ostrea lurida was once abundant in coastal waters of the Pacific Northwest (PNW) but was decimated in the late 19th and early 20th centuries, largely due to overharvesting, habitat degradation and pollution. Since then, the non-native Pacific oyster Crassostrea gigas has replaced O. lurida as the dominant oyster species in...
Article
Full-text available
Although the clearance rates of planktotrophic bivalve larvae have been widely reported, post-oral particle processing is less well understood. Using a series of exposures to differently colored fluorescent polystyrene microbeads, we quantify several post-oral process in the larval gut, including gut fullness, gut passage time, and degree of mixing...
Conference Paper
Populations of the native Olympia oyster Ostrea lurida on the West Coast, USA, have declined since the arrival of early settlers and, in many estuaries, have been replaced by farmed populations of the non-native Pacific oyster Crassostrea gigas. It is not well understood what filtration services were lost with the extirpation of native oysters and...
Article
Full-text available
Ocean acidification (OA) is altering the chemistry of the world’s oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work...
Article
Full-text available
Numerous monitoring efforts are underway to improve understanding of ocean acidification and its impacts on coastal environments, but there is a need to develop a coordinated approach that facilitates spatial and temporal comparisons of drivers and responses on a regional scale. Toward that goal, the California Current Acidification Network (C-CAN)...
Article
Full-text available
In 2007, the US west coast shellfish industry began to feel the effects of unprecedented levels of larval mortality in commercial hatcheries producing the Pacific oyster Crassostrea gigas. Subsequently, researchers at Whiskey Creek Shellfish Hatchery, working with academic and government scientists, showed a high correlation between aragonite satur...
Article
Taurine is an essential or conditionally essential nutrient for many species of marine fish, especially during early development. There is growing evidence that marine fish larvae benefit from taurine-enriched rotifers; however, it is unknown if larvae benefit from taurine-enriched Artemia. We investigated the effects of taurine-enriched rotifers (...
Conference Paper
Full-text available
The native Olympia oyster Ostrea lurida was once abundant in coastal waters of the Pacific Northwest (PNW) but was decimated in the late 19th and early 20th centuries, largely due to overharvesting, habitat degradation and pollution. Since then, the non-native Pacific oyster Crassostrea gigas has replaced O. lurida as the dominant oyster species in...
Conference Paper
Historically clearance rates of bivalve larvae have been indirectly determined by measuring rates of decrease in concentrations of suspended algal cells using electronic particle counters; however, this method does not take into account production of fecal and pseudofecal particles that may be of similar size to uneaten algal cells, resulting in un...
Article
The naturally occurring taurine concentrations of rotifers (Brachionus sp.) may not be sufficient to meet the nutritional demands of several species of marine fish larvae. In this study, we evaluated the use of liposomes for taurine-enrichment of rotifers and compared them with standard methods in which taurine was dissolved in the rotifer enrichme...
Article
Full-text available
Ocean acidification results in co-varying inorganic carbon system variables. Of these, an explicit focus on pH and organismal acid–base regulation has failed to distinguish the mechanism of failure in highly sensitive bivalve larvae. With unique chemical manipulations of seawater we show definitively that larval shell development and growth are dep...
Conference Paper
Full-text available
Historically, feeding studies with bivalve larvae have indirectly measured feeding activity by measuring the decrease in concentrations of suspended algal cells using electronic particle counters; however, this method does not take into account production of fecal and pseudofecal particles that may be difficult to separate from uneaten algal cells,...
Article
Naturally-occurring taurine concentrations in rotifers may not meet the nutritional requirements for species of cultured marine fish during the larval stages. Traditional methods for the enrichment of rotifers by immersion in a nutrient solution may be inefficient and may promote the growth of pathogenic bacteria. Microparticles, spe- cifically wax...
Conference Paper
Full-text available
Uptake of atmospheric CO2 by oceans, resulting in ocean acidification (OA), is predicted to significantly change the carbonate chemistry of many marine ecosystems in this century. Calcifying marine bivalves are commercially and ecologically valuable and their larvae have been reported to be the most sensitive life stage to OA effects. Research on t...
Article
Full-text available
The Olympia oyster, Ostrea lurida Carpenter, was formerly widespread in many US Pacific coast estuaries. Following dramatic declines in the late 1800s and early 1900s, this species is now the focus of renewed restoration efforts. Restoration is undertaken for brood stock rehabilitation as well as a range of ecosystem services such as filtration; ho...
Article
Acidified waters are impacting commercial oyster production in the U.S. Pacific Northwest, and favorable carbonate chemistry conditions are predicted to become less frequent. Within 48 h of fertilization, unshelled Pacific oyster (Crassostrea gigas) larvae precipitate roughly 90% of their body weight as calcium carbonate. We measured stable carbon...
Article
We report results from an oyster hatchery on the Oregon coast, where intake waters experienced variable carbonate chemistry (aragonite saturation state , 0.8 to . 3.2; pH , 7.6 to . 8.2) in the early summer of 2009. Both larval production and midstage growth (, 120 to , 150 mm) of the oyster Crassostrea gigas were significantly negatively correlate...
Conference Paper
Despite numerous studies that have highlighted the benefits of filter-feeding bivalves in estuarine ecosystems, little attention has been paid to the Olympia oyster (Ostrea lurida). We have measured allometric relationships between filtration rates and body weights at several temperatures for Pacific and Olympia oysters fed on microalgae. In additi...
Article
We determined if acute exposure (24 h) of developing Pacific oyster eggs to high pCO2 (approx. 1400matm) had a detrimental effect on subsequent development when cultured under ambient pCO2 conditions. After exposure, high pCO2 conditions resulted in a higher proportion of abnormal larvae and a smaller average shell width compared with eggs exposed...
Poster
We determined if acute exposure (24 h) of developing Pacific oyster eggs to high pCO2 (approx. 1400matm) had a detrimental effect on subsequent development when cultured under ambient pCO2 conditions. After exposure, high pCO2 conditions resulted in a higher proportion of abnormal larvae and a smaller average shell width compared with eggs exposed...
Conference Paper
Full-text available
Despite numerous studies that have highlighted the benefits of filter-feeding bivalves in estuarine ecosystems, little attention has been paid to the Olympia oyster (Ostrea lurida). We have measured allometric relationships between filtration rates and body weights at several temperatures for Pacific and Olympia oysters fed on microalgae. The effec...
Article
Salmonella enterica is the leading cause of laboratory-confirmed foodborne illness in the United States and raw shellfish consumption is a commonly implicated source of gastrointestinal pathogens. A 2005 epidemiological study done in our laboratory by Brands et al., showed that oysters in the United States are contaminated with Salmonella, and in p...
Article
Dietary iodine may play an important role in the nutritional health of freshwater fish larvae. Artemia, commonly used for the culture of larval zebrafish (Danio rerio), contain low concentrations of iodine when compared with wild-caught zooplankton. Iodine concentrations of Artemia can be increased using wax spray beads (WSB) containing potassium i...
Chapter
Introduction Delivery of high-molecular-weight proteins, carbohydrates, and water-insoluble nutrients Delivery of lipids Delivery of low-molecular-weight, water-soluble nutrients Literature cited Conclusions
Article
Selective breeding programs for improving Pacific oyster (Crassostrea gigas) stocks are expensive, labor-intensive, and typically rely on lengthy field trials in which selection for survival is compromised by inherent stochasticity of outbreaks of “summer mortality syndrome.” Reliable laboratory assays that identify and eliminate poor-performing fa...
Article
Spray-dried zein particles (SDZP), spray-water zein particles (SWZP) and gelatin-alginate beads (GAB) were prepared containing a defined dietary mixture and their performances were compared for delivering the soluble fraction of protein hydrolysates. Measures of performances of these three different microbound particle (MBP) types included inclusio...
Article
Full-text available
Sessile inhabitants of marine intertidal environments commonly face heat stress, an important component of summer mortality syndrome in the Pacific oyster Crassostrea gigas. Marker-aided selection programs would be useful for developing oyster strains that resist summer mortality; however, there is currently a need to identify candidate genes assoc...