Oyster Demand Adjustments to Alternative Consumer Education and Post Harvest Processes in Response to Vibrio vulnificus – A Pilot Study Ash Morgan, William Huth, Greg Martin University of West Florida CNREP, New Orleans, May 2007

Vibrio v. Vibrio v. is a bacterium Found naturally in estuarine or brackish coastal waters Higher concentrations in summer months Filter-feeding shellfish concentrate Vibrio v. in tissues

Gulf of Mexico Oyster Industry Vital resource Gulf of Mexico oyster industry 1994-2003 Average annual landings of eastern oyster = $47 million (82%) Gulf also supports recurring Vibrio v. incidences

Human Health Risk? Risk of life-threatening illnesses (acute septicemia or blood poisoning) to individuals with certain health conditions Liver disease Diabetes Cancer Weakened immune system

Actual Risks 1989 – 2002 Cocoran (1998) FDA recorded 341 Vibrio v.-related serious illnesses 98% associated with consuming raw oysters 179 resulted in deaths Cocoran (1998) 50 people become ill and 10 die each year through eating raw Gulf Coast oysters contaminated with Vibrio v.

Industry Cause for Concern? Recurring incidences Raise consumer awareness of product safety Increase perceived risk associated with oyster consumption ISSC survey One-third of respondents reduced oyster consumption in 2003 Primary reason Personal heath concerns Lipton (1997) $43 million loss due to increased awareness among consumers

Research Objectives Measure changes in oyster demand as a function of perceived risk Negative and positive information treatments 1) Quantify welfare losses due to news of Vibrio v. on demand for oysters 2) Quantify effects of different educational treatments (medium*source) in mitigating welfare losses 3) Quantify differences in risk perceptions contingent on PHP alternatives and price points

Research Strengths Strong policy application Priority topics: Industry and institutional interest Fit with ISSC/IFAS research Priority topics: ISSC Consumer education strategies to better inform oyster consumers of actual risks associated with Vibrio v. IFAS socioeconomic impacts from regulatory issues in the shellfish industry focus on the economic consequences of PHP requirements

Research Strengths FDA mandates Development and implementation of educational and outreach programs Inform consumers about risks associated with Vibrio v. Florida Vibrio v. Risk Reduction Plan for Oysters “Consumer education first and foremost tool to reduce illness related to Vibrio v.”

Background Shulstad and Stoevener (1978) - Pheasants Swartz and Strand (1981) – Baltimore oysters Smith et al. (1988) – Milk Brown and Schrader (1990) – Eggs Wessells et al. (1995) – Mussels Parsons et al. (2006) - Pfiesteria

Background Significant welfare losses due to Pfiesteria-related fish kills Positive information little impact on consumer behavior Individuals are not responsive to “expert” risk information Could be due to source credibility issues

Survey Design Follow Parsons et al. (2006) framework 2-stage web-based contingent behavior analysis Provide respondents with information treatments Respondents asked series of CB questions Elicit oyster demand preferences under different information scenarios

Stage One Traditional telephone survey Pre-treatment baseline data Oyster consumption experience, attitudes, preferences Awareness/perceptions of health risks Demographic data Respondents asked to participate in Stage 2

Stage Two Respondents sent link to project web site Unobtrusive identifier code Respondents subject to different media treatments*source Change in oyster meals consumed

Treatments Fictitious newspaper article Based on actual report Death caused by consuming contaminated raw oysters

Treatments*Source Information treatments Sources Tri-fold color brochure 30 second video PSA format Newspaper / magazine format Sources ISSC/Food and Drug Administration (FDA) A fictitious “brand identity” that identifies Vibrio v. education programs (“American Shellfish Foundation”) Control group (no message source identified)

Example – Brochure/ISSC-FDA Respondents informed brochure is published and distributed by the U.S. Food and Drug Administration (FDA) and the Interstate Shellfish Sanitation Conference (ISSC). Brief description of ISSC and FDA mission and funding source.

Generic PHP Treatment Focus of oyster industry on PHP treatments 4 FDA-approved PHP systems Pressurized Pasteurized Freezing Irradiation

PHP Respondents exposed to textual material containing non-technical educational information about the concept and efficacy of various types of PHP treatments to mitigate the risk of Vibrio v. infection. 2 final CB questions Consumption of PHP-treated oyster Consumption of PHP-treated oyster + price increase

Model

Estimation 14 parameters to be estimated: price increase price decrease news 9 media*source treatments PHP PHP + price increase Estimate Demand Curve Demand Shifters

Results Quantify the effectiveness of all media x source treatments, including PHP and price premium, in mitigating any negative welfare effects from the perceived risk effects of Vibrio v. Provide interested parties such as the ISSC with data to support further development of interventions that improve consumer education strategies and risk mitigation.

Descriptive Stats n=366 58.8% are oyster consumers Mean meals per month = 2.2 77% eat 1 to 2 meals per month 33.2% eat raw oysters 45% in home Oysters safe to eat? Very safe – 18.7% Somewhat safe – 40.9% Somewhat unsafe – 19.5% Very unsafe – 7.1% Don’t know – 13.7%

Descriptive Stats Male – 36.9% Statistically different Males More likely to consume oysters More likely to consume raw oysters More likely to perceive oysters as safe to consume More likely to consume oysters in a restaurant

Descriptive Stats Cooked and raw equally likely to cause illness? No – 75.3% Internet access – Yes – 55.2% Source credibility – time spent on screen No source – 117.5 seconds ISSC/FDA – 104.3 seconds Non-govt org – 157.5 seconds