Campylobacteriosis, caused by bacteria in the genus Campylobacter, is the most common source of human bacterial gastroenteritis worldwide. A department of health investigation traced a 2021 outbreak in Rhode Island to the consumption of raw oysters. Indigenous to the gastrointestinal tract of birds, indirect transfer of Campylobacter to oysters during bird interactions with commercial oyster farming gear may be responsible . Due to these concerns, oyster farmers must maintain an operational plan describing mitigation strategies to minimize risks associated with bird interactions. However, data on Campylobacter transfer from seabirds to oysters is lacking. G oals of this study include 1) test the effectiveness of a non-lethal bird deterrent, 2) enumerate Campylobacter in seabird species found in the northern Gulf of Mexico, and 3) survey oysters for Campylobacter and describe the similarity between isolated strains from oysters and seabirds.
Six experimental floating cages were deployed at a farm site in coastal Alabama, three equipped with bird deterrents (zip ties) and three controls. C ameras monitored the efficacy of the deterrents. Campylobacter incidence in seabird fecal matter was determined using a selective and differential media. A n enrichment procedure was used to detect Campylobacter in oysters.
Deterrents decreased bird interactions with gear 8-fold (Fig. 1). Approximately 7.5% of bird feces were positive for Campylobacter (Table 1). Sequencing of the 16S rDNA identified the isolates as C. lari subsp. concheus . This species has not been confirmed as a human pathogen.