Carolyn Friedman

Select Pubs

Estes, R.M., Friedman, C.S., Elston, R.A., and Herwig, R. 2004. Pathogenicity of shellfish hatchery bacterial isolates to Pacific oyster larvae, Crassostrea gigas: A microplate assay. Dis Aquat Org. In press.
Friedman, C.S. and Finley, C.A. 2004. Evidence for an anthropogenic introduction of “Candidatus Xenohaliotis californiensis”, the etiological agent of withering syndrome, into northern California abalone populations via conservation efforts. Can J Fish Aquat Sci. In press.
Friedman, C.S., Biggs, W, Shields, J.D. and Hedrick, R.P. 2002. Transmission of Withering Syndrome in black abalone, Haliotis cracherodii Leach. J Shellfish Res 21(2):817-824.
Friedman, C.S., Trevelyan, G., Mulder, E.P., and Fields, R. Development of an oral administration of oxytetracycline to control losses due to withering syndrome in cultured red abalone Haliotis rufescens. Aquaculture 224:1-23.

Prospective graduate students may contact this person about availability as a faculty advisor.

My laboratory focuses on the examination of infectious and non-infectious diseases of wild and cultured marine invertebrates. Another focus of our laboratory is the conservation of marine invertebrates, particularly abalone. Our major projects currently are as follows:

Examination of a mass mortality of the Pacific oyster, Crassostrea gigas on the west coast of the United States.
Herpes-like viral infection of Pacific oysters.
Development of tools to control and diagnose Withering Syndrome in abalone.
An examination of the distribution of a herpes virus in oysters cultured in North America.
Restoration of the pinto abalone, Haliotis kamtschatkana, in Washington State.
Captive rearing and conservation of the endangered white abalone, Haliotis sorenseni.

Pacific Oyster Mortality

We are focusing on the relationship between environmental stress, culture practices, oyster stress response, and family lines on survival. This interdisciplinary project involves researchers in Washington State (University of Washington and Pacific Shellfish Institute), Oregon (Oregon State University) and California (UC Davis–Bodega Marine Lab) and combines field trials, laboratory challenges and molecular techniques.

Oyster Herpes Virus

Through a multi-institutional project, we are assessing whether a herpes virus that has caused significant problems in the French and southern Pacific (e.g. new Zealand) oyster hatcheries is present in North America. This will be accomplished using a PCR test for viral DNA.

Withering Syndrome

We are developing an oral therapeutic method to reduce the intensity of infection of the causative agent (a rickettsial bacterium) and associated losses due to Withering Syndrome (WS). In addition, we are optimizing a previously developed PCR assay to detect bacterial DNA in tissue, feces, and water samples. The goal of this project is to develop a commercially feasible treatment for WS under FDA guidance and to develop rapid and reliable detection methods.

In a second study, we are examining the influence of food availability and temperature on the development of WS in red abalone infected with the WS-bacterium, a key factor in causing the disease in this abalone species. We are also investigating the relationship between temperature and WS in black abalone, a species that is more susceptible to the bacterium than are red abalone. As many physiological alterations occur prior to the onset of clinical WS, we are examining alterations in tissue turn-over and glycogen storage in abalone infected with the WS-bacterium versus those that are uninfected. In conjunction with Dr. Ron Tjeerdema’s lab at UC Davis, we are also determining alterations in storage products and energetics (ATP levels) during the development of clinical WS.

A third focus is the differential susceptibility of multiple abalone species (including the endangered white abalone, H. sorenseni, and the local pinto abalone, H. kamschatkana kamschatkana) to the WS-bacterium and WS.

Pinto Abalone Restoration and Larval Dispersal

In a threatened species, initial efforts to rehabilitate a species should be focused on obtaining the necessary information for a species recovery plan. This plan should examine the potential for rehabilitation first. If intervention is deemed necessary, supplementation should only proceed following research into the prospective impact of such a program on the wild target populations (Waples 1991). Our intention in this study is to obtain the baseline information necessary to make informed decisions on whether a supplementation program in pinto abalone should proceed. This information includes derivation of the population demographics around the SJI (diver surveys and genetic analyses), examining and testing culture methods that maximize both the genetic variation and the survivability of outplanted individuals, and soliciting the opinions of stakeholders through a workshop.

Understanding larval dispersal dynamics is imperative for interpretation of stock structure and population dynamics, and for proper management of marine species, especially declining species (Pinto abalone). Research on dispersal and recruitment of broadcast spawning species is limited, and much research has relied on untested assumptions that larvae behave as passively drifting particles. We propose to:

Develop larval Pinto abalone tagging methods using the mtDNA cytochrome oxidase gene, and assess its utility for high throughput detection of target species presence in seawater samples.
Characterize larval dispersal patterns under experimental mesocosm conditions and via tagged larval field experiments.
Calculate juvenile abalone abundances at index sites, and evaluate based on predictions from larval dispersal predictions.
Use our new tools for tracking invertebrate larvae to provide a basis for sound management and enhancement of Pinto abalone by determining larval dispersal and juvenile recruitment patterns.